Check your e-invoice for free.
Upload an XRechnung file or a ZUGFeRD PDF. The checking program of Germany’s coordination office for IT standards (KoSIT validator 1.6.3) tests it on our server in Germany. You then see which rules the file breaks, with the common ones explained in plain English and often how to fix them.
For invoices between businesses in Germany, e-invoices are becoming mandatory (section 27(38) of the German VAT Act, UStG). From 1 January 2027 this applies to businesses with more than €800,000 turnover in the previous year. From 1 January 2028 it covers all of them, with exceptions such as small businesses under the German small business scheme (“Kleinunternehmer”) and invoices up to €250 gross.
Result of the check.
Technical check, not tax advice
Only the invoice file inside the PDF was checked. The check does not look at the visible part of the PDF.
Rules the check applied
- File structure against the schema of its format
- EN 16931 rules
- XRechnung rules
- Peppol BIS Billing 3.0 rules
An invoice can be wrong in its content even when the check finds nothing, for example with the wrong VAT rate. Germany’s Federal Ministry of Finance points this out in its letter of 15 October 2025, para. 35a. What the check does not cover
Showing the first 200 places, errors first.
Product names mentioned here, including OpenAI’s ChatGPT, are trademarks of their respective owners. We are not a partner of these companies.
The check tests the file on a technical level. It looks at whether the file follows the rules of the EN 16931 standard. For an XRechnung it also applies the XRechnung rules, and for a Peppol invoice the Peppol BIS Billing 3.0 rules. Your tax advisor judges whether the invoice is right for tax purposes, such as the VAT rate, the required details and input tax deduction. This result is not tax advice.
Not tax advice
The check tests the file on a technical level. It looks at whether the file follows the rules of the EN 16931 standard. For an XRechnung it also applies the XRechnung rules, and for a Peppol invoice the Peppol BIS Billing 3.0 rules. Your tax advisor judges whether the invoice is right for tax purposes, such as the VAT rate, the required details and input tax deduction. This result is not tax advice.
File structure
Germany’s Federal Ministry of Finance (BMF) calls it a format error when a file does not meet the technical requirements of its format.
What this means
Germany’s Federal Ministry of Finance (BMF) calls it a format error when a file does not meet the technical requirements of its format. For VAT purposes such a file counts as an “other invoice in another electronic format” (“sonstige Rechnung”). The kind of format error makes no difference (BMF letter of 15 October 2025, para. 6a). Source, retrieved 23 October 2026
The checking program stopped partway through.
What this means
The checking program stopped partway through. The file matched the template of its format (the schema), and then one rule could not run to the end. So there is no telling whether the file meets every rule. The other messages come from checking steps that ran to the end.
EN 16931 rules
If the check reports an error against an EN 16931 rule, the file technically no longer counts as an invoice under that standard.
What this means
If the check reports an error against an EN 16931 rule, the file technically no longer counts as an invoice under that standard. Germany’s Federal Ministry of Finance (BMF) says this technical view does not decide VAT questions. Without a format error, the file is in principle still an e-invoice under section 14 of the German VAT Act, UStG (BMF, 15 October 2026, paras. 22–23). For the BMF, an error can only be a content error if it concerns a detail that VAT law requires on invoices (BMF, 15 October 2026, para. 22, and 15 October 2025, para. 35a). Whether that applies to your invoice is for your tax advisor to judge. Source, retrieved 23 October 2026 Further source, retrieved 23 October 2026
XRechnung rules
These rules belong to the XRechnung rule set and go further than the EN 16931 standard.
What this means
These rules belong to the XRechnung rule set and go further than the EN 16931 standard. For VAT purposes, any format that follows this standard is permitted (VAT Application Decree, UStAE, section 14.1(11)). Which one applies is for you to agree with your customer or supplier (section 14.1(12)). For Germany’s Federal Ministry of Finance (BMF), a rule error can only be a content error if it concerns a required invoice detail under VAT law (BMF, 15 October 2026, para. 22). Whether that applies to your invoice is for your tax advisor to judge. For invoices to public authorities and other public contracting bodies, further rules apply alongside VAT law, such as the federal E-Invoicing Ordinance (E-Rechnungsverordnung; paras. 24 and 25). Source, retrieved 23 October 2026 Further source, retrieved 23 October 2026
Peppol BIS Billing 3.0 rules
These rules belong to the Peppol BIS Billing 3.0 rule set and go further than the EN 16931 standard.
What this means
These rules belong to the Peppol BIS Billing 3.0 rule set and go further than the EN 16931 standard. For VAT purposes, any format that follows this standard is permitted, even one that does not come from Germany (VAT Application Decree, UStAE, sections 14.1(11) and 14.1(12)). Which one applies is for you to agree with your customer or supplier (section 14.1(12)). For Germany’s Federal Ministry of Finance (BMF), a rule error can only be a content error if it concerns a required invoice detail under VAT law (BMF, 15 October 2026, para. 22). Whether that applies to your invoice is for your tax advisor to judge. Source, retrieved 23 October 2026 Further source, retrieved 23 October 2026
ZUGFeRD profile
Germany’s Federal Ministry of Finance counts ZUGFeRD from version 2.0.1 among the permitted e-invoice formats, except the MINIMUM and BASIC WL profiles (UStAE section 14.1(14)). Source, retrieved 23 October 2026
What this means
Germany’s Federal Ministry of Finance counts ZUGFeRD from version 2.0.1 among the permitted e-invoice formats, except the MINIMUM and BASIC WL profiles (UStAE section 14.1(14)). Source, retrieved 23 October 2026
Outside this check
This check does not cover this version or format.
What this means
This check does not cover this version or format. It covers XRechnung 3.0 and invoices that follow the EN 16931 standard without additions. For Peppol BIS Billing 3.0, it checks files that start with Invoice or CreditNote.
: The buyer reference is missing, rule BR-DE-15
- How to fix it
- Enter the reference your customer gave you. For German federal authorities this is the Leitweg-ID, which the authority states with its order. If you have no reference, ask your customer for one.
- VAT, in general
- Germany’s Federal Ministry of Finance cites a missing buyer reference (BT-10) as an example of a rule error that does not matter for VAT. Whether your customer needs the entry anyway depends on your agreement with them. Invoices to German federal authorities need the Leitweg-ID in this field (section 5 of the federal E-Invoicing Ordinance, E-Rechnungsverordnung; BMF, 15 October 2026, paras. 24 and 25). Source, retrieved 23 October 2026
In Lexware Office
Lexware Office keeps the Leitweg-ID on the customer record, under contacts (“Kontakte”), edit contact (“Kontakt bearbeiten”), section “E-Rechnung”, field “Leitweg ID”. First check that Lexware Office created the invoice as an XRechnung. Once the ID is in place, open the invoice for editing, save it and download the XML file again.
Vendor’s help page, retrieved 23 October 2026In sevdesk
sevdesk calls the buyer reference “Kundenreferenz / Leitweg-ID”. The field sits in the lower part of the invoice form under “Weitere Optionen”. If the Leitweg-ID belongs on every invoice to this customer, switch on “E-Rechnung Standard” in the contact and enter it there. According to the help page, sevdesk writes 0 as the customer reference when you leave the field empty.
Vendor’s help page, retrieved 23 October 2026In DATEV
In DATEV Auftragswesen next, the buyer reference belongs in the customer record, in the customer reference field (“Kundenreferenz”). A public authority’s Leitweg-ID goes there too. The program uses the field once “E-Rechnung” is selected as the invoice format under general invoice data (“Allgemeine Rechnungsdaten”) for that customer. The field also decides how the invoice is sent. Without an entry, it goes out by email as ZUGFeRD. With a TRAFFIQX ID (prefixed “TX:”) or a Leitweg-ID, it goes through a portal, provided the recipient is registered there. For an invoice that is still a draft, select the customer in it again so the draft picks up the changed details. DATEV E-Rechnungsschreibung calls the same field “Leitweg-ID/ Kundenreferenz” (document no. 1028945).
Vendor’s help page, retrieved 23 October 2026What the rule requires
XRechnung requires a buyer reference (BT-10) on every invoice. The rule reports an error when that entry is missing or holds nothing but spaces. EN 16931 lists the buyer reference as optional; this XRechnung rule makes it mandatory.
- Common cause
- This happens when the customer never supplied a reference, or when it is missing from the customer record in the invoicing software.
- Details concerned
- BT-10 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The seller’s VAT ID and tax number are missing, rule BR-DE-16
- How to fix it
- Store the VAT ID or the tax number in the seller’s company settings, then check that the number appears in the next file you create. If the seller uses a tax representative, the rule accepts the representative’s details (BG-11).
- VAT, in general
- The German VAT Act lists the supplier’s tax number or VAT ID as a required invoice detail (section 14(4) sentence 1 no. 2 UStG). A mapping table by KoSIT, Germany’s coordination office for IT standards, and FeRD, the German e-invoicing forum, puts it in BT-31 and BT-32. Germany’s Federal Ministry of Finance recommends basing e-invoices on this table (BMF, 15 October 2026, paras. 8 and 9). Source, retrieved 23 October 2026
In Lexware Office
Lexware Office stores your tax number and VAT ID under settings (“Einstellungen”, gear icon), general settings (“Allgemeine Einstellungen”). Its help lists one or both of them as a requirement for creating e-invoices.
Vendor’s help page, retrieved 23 October 2026In sevdesk
In sevdesk, your VAT ID (“Umsatzsteuer-ID”) and your tax number (“Steuernummer”) go into the main menu under “Einstellungen”, “Unternehmen”, section “Buchhaltung & Steuern”.
Vendor’s help page, retrieved 23 October 2026In DATEV
DATEV Auftragswesen next takes your company’s VAT ID and tax number from its configuration. Open configuration (“Konfiguration”), go to “E-Rechnung”, enter one of the two numbers under details of your company (“Angaben zu Ihrem Unternehmen”) and click save (“Speichern”). DATEV says Auftragswesen next refuses to finish an invoice while both are missing and shows the message “Mangelhafte Angaben” (insufficient details). In the desktop program DATEV Auftragswesen, the tax number sits under “Stammdaten”, “Unternehmensdaten”, “Unternehmen/Vereinigung”, on the tax office tab (“Finanzamt”, document no. 1048539).
Vendor’s help page, retrieved 23 October 2026What the rule requires
The rule applies once a line, an allowance or a charge uses VAT category S, Z, E, AE, K, G, L or M. XRechnung then asks for the seller’s tax details: the VAT identification number (BT-31), the tax number (BT-32) or a tax representative (BG-11). The seller is the business issuing the invoice. S stands for supplies taxed at a rate above zero, AE for reverse charge.
- Common cause
- The company settings in the invoicing software hold neither a tax number nor a VAT ID, or the software leaves them out of the file. If lines use category S, the check also reports the same gap as BR-S-02, an EN 16931 rule.
- Details concerned
- BT-31, BT-32, BG-11 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: No delivery date or service period, rule BR-DE-TMP-32
- How to fix it
- Add the delivery date or an invoicing period for the whole invoice. If you prefer periods per line, give every line one, including minor items such as shipping.
- VAT, in general
- The German VAT Act lists the date of the supply of goods or services as a required invoice detail (section 14(4) sentence 1 no. 6 UStG). A mapping table by KoSIT, Germany’s coordination office for IT standards, and FeRD, the German e-invoicing forum, puts it in BT-72, BG-14 and BG-26. Germany’s Federal Ministry of Finance (BMF) recommends basing e-invoices on this table (BMF, 15 October 2026, paras. 8 and 9). According to the BMF, every required detail belongs in the machine-readable part of an e-invoice (BMF, 15 October 2025, para. 35). Source, retrieved 23 October 2026
In Lexware Office
In the Lexware Office invoice editor the date sits in the customer details (“Kundenangaben”), in the delivery date field (“Lieferdatum”). Switch that field to service period (“Leistungszeitraum”) and enter a start and end date, or to service date (“Leistungsdatum”) for a single day. Lexware asks for the service period on e-invoices.
Vendor’s help page, retrieved 23 October 2026In sevdesk
The sevdesk invoice form has a “Lieferdatum” (delivery date) field. To have it filled in on every new invoice, turn on “Lieferdatum automatisch setzen” under “Einstellungen”, “System”, “Aufträge & Rechnungen”. The help page leaves open which date sevdesk enters, so look at it before you send the invoice.
Vendor’s help page, retrieved 23 October 2026In DATEV
In DATEV Auftragswesen next, the date goes into the date of supply field (“Liefer- & Leistungsdatum”) while you edit the invoice. Clicking the icon that belongs to it switches the field to period of supply (“Liefer- & Leistungszeitraum”), where you enter a period instead. According to DATEV’s help, Auftragswesen next will not save the invoice while this field is empty.
Vendor’s help page, retrieved 23 October 2026What the rule requires
XRechnung recommends that the invoice states when goods were delivered or services performed. One of these is enough: the delivery date (BT-72), an invoicing period for the whole invoice (BG-14) or a period on each line (BG-26). The XRechnung rule set classifies this rule as a notice.
- Common cause
- The invoice lacks both a delivery date and an invoicing period. The notice also appears when only some lines carry a period, for example when a shipping line has none.
- Details concerned
- BT-72, BG-14, BG-26 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The line total does not match the lines, rule BR-CO-10
- How to fix it
- Set the line total (BT-106) to the exact sum of all line net amounts. Discounts and charges on the whole invoice go into their own entries (BT-107 and BT-108) and leave the line total unchanged.
In DATEV
DATEV Auftragswesen next works out each line amount itself as quantity times price. It takes the total of all lines from the subtotal (“Zwischensumme”) in the invoice’s totals block. The desktop program DATEV Auftragswesen fills in this total automatically as well (document no. 1037112).
Vendor’s help page, retrieved 23 October 2026What the rule requires
The invoice states a sum of all line net amounts (BT-106). That sum has to equal the net amounts of the individual lines (BT-131) added together, to the cent. The rule rounds the added-up lines to two decimal places before comparing.
- Common cause
- The total no longer fits if a discount on the whole invoice was already taken off it, or if someone edited a line afterwards. Rounding lines and total in different ways has the same effect.
- Details concerned
- BT-106, BT-131 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The gross total does not equal net plus VAT, rule BR-CO-15
- How to fix it
- Make the three amounts agree to the cent: gross (BT-112) equals net (BT-109) plus VAT (BT-110). List the VAT total in the invoice currency exactly once. For rounding with fixed gross prices, ask your tax advisor.
- VAT, in general
- The EN 16931 standard calculates from the amount without VAT. For supplies at fixed gross prices, Germany’s Federal Ministry of Finance (BMF) notes that this can cause rounding differences (BMF, 15 October 2026, para. 18). For e-invoices based on gross prices and issued by 31 December 2027, the BMF will not object to a simpler layout (para. 19). The machine-readable part then gives only the totals per VAT rate or exemption, with the VAT amount. The individual lines go in an embedded attachment that people can read, and the machine-readable part refers to it clearly. Source, retrieved 23 October 2026
In DATEV
In DATEV Auftragswesen next all three amounts come from the totals block of the invoice. The net figure is the total line (“Summe”), the VAT is the sum of the tax amounts and the gross figure is the final amount (“Endbetrag EUR”). DATEV’s help states that Auftragswesen next builds e-invoices from net prices only (document no. 1019619).
Vendor’s help page, retrieved 23 October 2026What the rule requires
The invoice total including VAT (BT-112) has to be the total without VAT (BT-109) plus the invoice VAT amount (BT-110). The rule compares to the cent.
- Common cause
- The software rounded gross, net and VAT separately, for example because prices are fixed as gross amounts and it works back to net and VAT. The result is a few cents off. The check also reports this rule when the VAT total in the invoice currency appears twice in the file, or not at all. In files that start with CrossIndustryInvoice, the rule reports nothing as long as the file’s gross total equals its net total.
- Details concerned
- BT-112, BT-109, BT-110 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The amount due does not add up, rule BR-CO-16
- How to fix it
- Enter amounts already paid, such as prepayments, as the paid amount (BT-113) and any rounding as the rounding amount (BT-114). The amount due then works out as gross total minus paid amount plus rounding.
- VAT, in general
- For final invoices after partial payments, Germany’s Federal Ministry of Finance will not object to a simpler layout until 30 June 2030. The payments received appear as one sum in the paid amount (BT-113), with the details in the invoice note (BT-22). Source, retrieved 23 October 2026
In DATEV
DATEV Auftragswesen next calculates the amount due on its own. On a final invoice it enters the down payments received as the amount already paid. According to DATEV’s field list, Auftragswesen next cannot send a rounding amount (BT-114) at present.
Vendor’s help page, retrieved 23 October 2026What the rule requires
The amount due for payment (BT-115) must equal the invoice total including VAT (BT-112), less any amount already paid (BT-113), plus any rounding amount (BT-114). Without the last two entries, the amount due has to match the total including VAT exactly.
- Common cause
- Something was deducted from or added to the amount due without appearing as a paid amount or a rounding amount. That might be a prepayment mentioned only in the invoice text, or an amount due changed by hand.
- Details concerned
- BT-115, BT-112, BT-113, BT-114 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The VAT breakdown lacks category S, rule BR-S-01
- How to fix it
- Compare the lines with the VAT breakdown. Every category used on a line, an allowance or a charge needs its own entry in the breakdown. Which category applies to your supply is a question for your tax advisor.
In DATEV
DATEV Auftragswesen next fills in the VAT category and rate for each line and for the VAT breakdown on its own. It derives them from the tax rate and any exemption you choose on the invoice and in the item data. The desktop program DATEV Auftragswesen sets the category from the document settings, the customer’s tax status and the type of item (document no. 1048790).
Vendor’s help page, retrieved 23 October 2026What the rule requires
This rule is about VAT category S (standard rated), meaning supplies taxed at a rate above zero. If an invoice line, an allowance or a charge uses S, the VAT breakdown (BG-23) needs at least one entry with category S. In files that start with Invoice or CreditNote, the rule also catches the reverse case. Here S appears in the breakdown even though every line, allowance and charge uses another category.
- Common cause
- The lines and the VAT breakdown have drifted apart, for instance because someone changed the category in only one of the two places. If the breakdown is missing altogether, other messages such as BR-CO-18 appear as well.
- Details concerned
- BT-151, BT-95, BT-102, BT-118 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The specification identifier is missing, rule BR-01
- How to fix it
- The invoicing software writes this identifier when it creates the file. Check which e-invoice format is selected there, such as XRechnung or ZUGFeRD. If the software has no such setting, contact its vendor.
In DATEV
According to DATEV’s help, Auftragswesen next fills in the format identifier automatically. DATEV gives the formats its programs send as XRechnung 3.0.2, ZUGFeRD in the EN 16931 profile and Peppol BIS Billing 3.0.20 (document no. 1049555).
Vendor’s help page, retrieved 23 October 2026What the rule requires
Every invoice needs a specification identifier (BT-24). It names the rule set the file follows: urn:cen.eu:en16931:2017#compliant#urn:xeinkauf.de:kosit:xrechnung_3.0 for XRechnung 3.0, or urn:cen.eu:en16931:2017 for a plain EN 16931 invoice.
- Common cause
- The invoicing software left the identifier empty or never wrote it. The check runs a checking program from KoSIT, Germany’s coordination office for IT standards, which picks its rules by this identifier. Without one, it rejects the file and names no individual rule.
- Details concerned
- BT-24 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: Seller contact holds both a name and a department, rule CII-SR-465
- How to fix it
- Keep either the name or the department in the seller contact, not both, then create the invoice again. If your invoicing software has no setting for this, contact its vendor.
In DATEV
In DATEV Auftragswesen next, your company’s contact point (BT-41) comes from configuration (“Konfiguration”), “E-Rechnung”, contact person field (“Ansprechpartner”). DATEV’s field list names no field for a department. According to DATEV, Auftragswesen next cannot currently send fields missing from that list.
Vendor’s help page, retrieved 1 November 2026What the rule requires
The rule applies to files that start with CrossIndustryInvoice. The seller contact point (BT-41) may appear only once on an invoice. The rule reports when the seller’s contact holds a person’s name (PersonName) and a department (DepartmentName) at the same time, because both entries count as BT-41. Under the EN 16931 standard this is a warning. For XRechnung, the checking program from KoSIT, Germany’s coordination office for IT standards, raises it to an error.
- Common cause
- The invoicing software holds both a contact person and a department for your own company and writes both into the seller contact.
- Details concerned
- BT-41 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: More than one description across supporting documents, rule CII-SR-475
- How to fix it
- If every document has exactly one description, the message only reflects how the rule counts. If one document has more than one description, remove the extra ones. In XRechnung, BR-TMP-4 reports that case too.
In DATEV
When you add an attachment in DATEV Auftragswesen next, the program fills its description (BT-123) with the file name automatically, according to DATEV’s field list. The list names no setting for this field.
Vendor’s help page, retrieved 1 November 2026What the rule requires
The rule applies to files that start with CrossIndustryInvoice. It counts the descriptions (BT-123) of all additional supporting documents with type code 916 (BG-24) across the whole invoice. If there is more than one, it reports, even when each document has only one description. According to KoSIT, Germany’s coordination office for IT standards, the rule checks in the wrong place. For XRechnung its checking program therefore lowers it to a notice, and the invoice still counts as meeting the rules. There, rule BR-TMP-4 checks each document on its own. For an invoice under the EN 16931 standard alone it stays a warning.
- Common cause
- The invoice carries two or more supporting documents, each with its own description. Less often, a single document has more than one description.
- Details concerned
- BT-123, BG-24 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: More than one attached file across supporting documents, rule CII-SR-476
- How to fix it
- If every document has exactly one file, the message only reflects how the rule counts. If one document has several files, give each file a document of its own. In XRechnung, BR-TMP-5 reports that case too.
In DATEV
When you add an attachment in DATEV Auftragswesen next, the program creates the attached document (BT-125) automatically, according to DATEV’s field list. The list names no setting for this field.
Vendor’s help page, retrieved 1 November 2026What the rule requires
The rule applies to files that start with CrossIndustryInvoice. It counts the attached files (BT-125) of all additional supporting documents with type code 916 (BG-24) across the whole invoice. If there is more than one, it reports, even when each document has only one file. According to KoSIT, Germany’s coordination office for IT standards, the rule checks in the wrong place. For XRechnung its checking program therefore lowers it to a notice, and the invoice still counts as meeting the rules. There, rule BR-TMP-5 checks each document on its own. For an invoice under the EN 16931 standard alone it stays a warning.
- Common cause
- The invoice carries two or more supporting documents, each with one attached file. Less often, a single document has several files.
- Details concerned
- BT-125, BG-24 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: Unknown scheme for a party identifier, rule BR-CL-10
- How to fix it
- Look up the code on the identifier reported. If it is not on the ISO 6523 ICD list, use the list code that fits the register, or leave the extra detail out. If your invoicing software writes the code, contact its vendor.
In DATEV
In DATEV Auftragswesen next, the seller identifier (BT-29) can only be entered as a line following the pattern ##BT-29:123456##, for example in the invoice’s note (“Hinweistext”). DATEV’s field list says nothing about an extra detail for the register. The buyer and payee identifiers (BT-46, BT-60) are missing from the list. According to DATEV, Auftragswesen next cannot currently send such fields.
Vendor’s help page, retrieved 1 November 2026What the rule requires
Identifiers of the seller, the buyer and the payee (BT-29, BT-46, BT-60) can carry an extra detail naming the register the identifier comes from (schemeID). That detail has to be a code from the ISO 6523 ICD list. The rule reports a code that is not on it. Under the EN 16931 standard and in XRechnung this is an error. Only for XRechnung with extension does the checking program from KoSIT, Germany’s coordination office for IT standards, lower the rule to a notice. The invoice then still counts as meeting the rules.
- Common cause
- The invoicing software writes a register code for an identifier that is missing from the ISO 6523 ICD list.
- Details concerned
- BT-29, BT-46, BT-60 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: Unknown scheme for an item classification, rule BR-CL-13
- How to fix it
- Look up the code on the classification of the line reported. If it is not on the UNTDID 7143 list, use the matching code from the list. If your invoicing software writes the code, contact its vendor.
In DATEV
The item classification (BT-158) is not in DATEV’s field list for Auftragswesen next. According to DATEV, the program cannot currently send fields missing from that list.
Vendor’s help page, retrieved 1 November 2026What the rule requires
An invoice line can place the item in a classification (BT-158, item classification identifier). It comes with an extra detail naming the classification the code belongs to (listID). That detail has to be a code from the UNTDID 7143 list. The rule reports a code that is not on it. Under the EN 16931 standard and in XRechnung this is an error. Only for the CVD variant of XRechnung does the checking program from KoSIT, Germany’s coordination office for IT standards, lower the rule to a notice. The invoice then still counts as meeting the rules. This variant supports the reporting duties of the Clean Vehicle Directive (CVD) in public procurement.
- Common cause
- The invoicing software writes a classification code for an item that is missing from the UNTDID 7143 list.
- Details concerned
- BT-158 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: Unknown scheme for an item standard identifier, rule BR-CL-21
- How to fix it
- Look up the code on the item identifier of the line reported. If it is not on the ISO 6523 ICD list, use the list code that fits the register, or leave the extra detail out. If your invoicing software writes the code, contact its vendor.
In DATEV
The item standard identifier (BT-157) is not in DATEV’s field list for Auftragswesen next. According to DATEV, the program cannot currently send fields missing from that list.
Vendor’s help page, retrieved 1 November 2026What the rule requires
An invoice line can name the item with an identifier under a standard (BT-157, item standard identifier). It comes with an extra detail naming the register that issued the identifier (schemeID). That detail has to be a code from the ISO 6523 ICD list. The rule reports a code that is not on it. How much this counts depends on the invoice format identifier. Under the EN 16931 standard it is an error. For XRechnung, the checking program from KoSIT, Germany’s coordination office for IT standards, lowers the rule to a warning. For XRechnung with extension it lowers it to a notice. As a warning or notice on its own, it leaves the invoice counting as meeting the rules.
- Common cause
- The invoicing software writes a register code for the item identifier that is missing from the ISO 6523 ICD list.
- Details concerned
- BT-157 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The seller name is missing, rule BR-06
- How to fix it
- Enter your business’s full name in the company settings and create the invoice again. Then check that the name appears in the new file.
In Lexware Office
In Lexware Office, the company name goes into company details (“Firmendaten”), which you open from the gear icon at the top right. Lexware lists the company name and address there as required fields for outgoing documents such as invoices. General settings (“Allgemeine Einstellungen”) take the name over from the company details on their own.
Vendor’s help page, retrieved 1 November 2026In sevdesk
In sevdesk, the company name sits in the main menu under settings (“Einstellungen”), company (“Unternehmen”), section general (“Allgemein”). According to sevdesk’s help, only one of the two fields company name (“Firmenname”) and managing director (“Geschäftsführer”) is required there.
Vendor’s help page, retrieved 1 November 2026In DATEV
In DATEV Auftragswesen next, your business name (BT-27, which DATEV calls legal name, “Rechtlicher Name”) comes from configuration (“Konfiguration”), “E-Rechnung”, field “Name”.
Vendor’s help page, retrieved 1 November 2026What the rule requires
Every invoice needs the seller name (BT-27), meaning the name of the business issuing the invoice. The rule reports an error when that entry is missing or holds nothing but spaces. In files that start with CrossIndustryInvoice, the name sits in the Name entry under SellerTradeParty. In files that start with Invoice or CreditNote, it sits in the RegistrationName entry under PartyLegalEntity.
- Common cause
- The company settings in the invoicing software hold no business name, or the software leaves it out of the file.
- Details concerned
- BT-27 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The seller’s VAT ID or tax number is missing, rule BR-S-02
- How to fix it
- Enter your VAT ID or your tax number in the company settings and create the invoice again. In an XRechnung, rule BR-DE-16 reports the same case.
In DATEV
In DATEV Auftragswesen next, your business’s VAT ID (BT-31) and tax number (BT-32) come from configuration (“Konfiguration”), “E-Rechnung”, fields VAT ID (“Ust.-IdNr.”) and tax number (“Steuernummer”).
Vendor’s help page, retrieved 2 November 2026What the rule requires
This rule is about VAT category S (standard rated), meaning supplies taxed at a rate above zero. If an invoice line uses S, the invoice needs a tax detail of the seller. That is the seller’s VAT identifier (BT-31), tax number (BT-32) or the VAT identifier of a tax representative (BT-63). Any one of the three satisfies the rule.
- Common cause
- The company settings in the invoicing software hold neither a VAT ID nor a tax number, or the software leaves them out of the file.
- Details concerned
- BT-151, BT-31, BT-32, BT-63 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The taxable amount for a VAT rate does not add up, rule BR-S-08
- How to fix it
- For each VAT rate, add up the net amounts of the lines, add the charges and take off the allowances. The result goes into the breakdown entry for that rate as its taxable amount (BT-116).
In DATEV
DATEV Auftragswesen next fills in the taxable amount per rate (BT-116) from the total in the invoice’s totals block. It sets the VAT category and rate (BT-118, BT-119) on its own from the tax rate and the exemption settings.
Vendor’s help page, retrieved 2 November 2026What the rule requires
This rule is about VAT category S, meaning supplies taxed at a rate above zero. The VAT breakdown (BG-23) gives a taxable amount (BT-116) for each rate. It has to be the sum of the net amounts of all lines with category S at that rate (BT-131). Charges on the whole invoice with the same category and rate are added (BT-99), and allowances are taken off (BT-92). In files that start with Invoice or CreditNote, the rule accepts a difference below one unit of the invoice currency, so below €1. In files that start with CrossIndustryInvoice, it compares to the cent.
- Common cause
- A line, an allowance or a charge carries a different VAT rate from the breakdown entry. Or a discount on the whole invoice was taken off in the breakdown. It does not appear in the file as an allowance of its own. Editing an amount by hand afterwards has the same effect.
- Details concerned
- BT-116, BT-131, BT-92, BT-99 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The VAT amount for a VAT rate is off, rule BR-S-09
- How to fix it
- In the entry reported, multiply the taxable amount by the rate and compare the result with the VAT amount. Also check that the rate in the entry matches the lines.
In DATEV
DATEV Auftragswesen next fills in the VAT amount per rate (BT-117) on its own, grouping the rates used on the lines. It derives the VAT category and rate (BT-118, BT-119) from the tax rate and exemption you choose.
Vendor’s help page, retrieved 2 November 2026What the rule requires
This rule is about VAT category S, meaning supplies taxed at a rate above zero. In every VAT breakdown entry (BG-23) with this category, the VAT amount (BT-117) has to match the taxable amount (BT-116) times the rate (BT-119). The rule accepts a difference below one unit of the invoice currency, so below €1.
- Common cause
- The VAT amount was worked out from a different rate or taxable amount than the one in the entry. This happens, for instance, when someone changes the rate or the taxable amount afterwards. BR-CO-17 checks the same calculation for every category, so it can appear alongside this rule.
- Details concerned
- BT-117, BT-116, BT-119 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The invoice net total does not add up, rule BR-CO-13
- How to fix it
- Check the sum: line total (BT-106) minus allowances (BT-107) plus charges (BT-108) gives the total without VAT (BT-109). Enter allowances and charges on the whole invoice as entries of their own.
In DATEV
In DATEV Auftragswesen next, the total without VAT (BT-109) comes from the total in the invoice’s totals block. The program works out each line amount itself as quantity times price.
Vendor’s help page, retrieved 2 November 2026What the rule requires
The invoice total without VAT (BT-109) has to equal the line total (BT-106), minus allowances (BT-107) plus charges (BT-108) on the whole invoice. The rule rounds to two decimal places and compares to the cent.
- Common cause
- A discount or charge on the whole invoice was applied to the total. It does not appear in the file as an entry of its own. Editing one of the amounts by hand afterwards has the same effect.
- Details concerned
- BT-109, BT-106, BT-107, BT-108 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The invoice VAT total does not match the VAT breakdown, rule BR-CO-14
- How to fix it
- Add up the VAT amounts in the breakdown and use the result, to the cent, as the invoice VAT total (BT-110). How to handle rounding differences is a question for your tax advisor.
In DATEV
In DATEV Auftragswesen next, the invoice VAT total (BT-110) comes from the sum of the tax amounts in the totals block. The program groups the amounts per rate (BT-117) on its own from the rates used on the lines.
Vendor’s help page, retrieved 2 November 2026What the rule requires
The invoice VAT total (BT-110) has to be the sum of the VAT amounts of all entries in the VAT breakdown (BT-117). The rule rounds that sum to two decimal places and compares to the cent.
- Common cause
- The software works out the invoice VAT total differently from the amounts per rate, for example rounding per line instead of per rate. Or an entry in the breakdown is missing or appears twice.
- Details concerned
- BT-110, BT-117 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: VAT amount and VAT rate do not match, rule BR-CO-17
- How to fix it
- In every breakdown entry, recalculate taxable amount times rate divided by 100. If the VAT amount differs, correct the rate or the amounts in your invoicing software and create the invoice again.
In DATEV
DATEV Auftragswesen next fills in the VAT amount per rate (BT-117) on its own, grouping the rates used on the lines. It takes the rate (BT-119) from the tax rate you choose.
Vendor’s help page, retrieved 2 November 2026What the rule requires
In every VAT breakdown entry (BG-23), the VAT amount (BT-117) has to equal the taxable amount (BT-116) times the rate (BT-119) divided by 100, rounded to two decimal places. The rule accepts a difference below one unit of the invoice currency, so below €1. In files that start with CrossIndustryInvoice, a difference of exactly €1 still passes. With a rate of zero, the VAT amount has to round to zero.
- Common cause
- The VAT amount in an entry was worked out from a different rate or taxable amount than the one shown. Or an entry with a rate of zero still carries a VAT amount.
- Details concerned
- BT-117, BT-116, BT-119 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: Unknown currency code, rule BR-CL-04
- How to fix it
- Look up the invoice currency in the file and use the three-letter code in capitals, EUR for euros. If your invoicing software writes the value, contact its vendor.
In DATEV
According to DATEV’s field list, DATEV Auftragswesen next sets the invoice currency (BT-5) to euro automatically.
Vendor’s help page, retrieved 2 November 2026What the rule requires
The invoice currency (BT-5, invoice currency code) has to be a three-letter code from the ISO 4217 list, such as EUR. The rule reports a value that is not on it. It tells upper and lower case apart, so eur, Euro or the € sign do not satisfy it. Files that start with Invoice or CreditNote hold the currency in the DocumentCurrencyCode entry, others in the InvoiceCurrencyCode entry.
- Common cause
- The invoicing software writes the currency as a word or symbol, such as Euro or €, or in lower case.
- Details concerned
- BT-5 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: Unknown unit of measure, rule BR-CL-23
- How to fix it
- Assign a code from the list to each unit in your invoicing software and create the invoice again. If the software has no setting for this, contact its vendor.
In DATEV
In DATEV Auftragswesen next, the unit (BT-130) comes from the saved item data or from the line. The program gives standard units their matching codes and gives custom units the code C62.
Vendor’s help page, retrieved 2 November 2026What the rule requires
Quantities on the invoice carry a code for their unit. This covers the quantity of a line (BT-130) and the base quantity of its price (BT-150). The code has to come from the list of UN/ECE Recommendation 20 with the Recommendation 21 extension. The rule reports a code that is not on it and tells upper and lower case apart. Under the EN 16931 standard this is an error. For XRechnung, the checking program from KoSIT, Germany’s coordination office for IT standards, lowers the rule to a warning. A warning on its own leaves the invoice counting as meeting the rules.
- Common cause
- The invoicing software writes the unit as it appears on the printed invoice, such as Stück or Std., instead of the code from the list.
- Details concerned
- BT-130, BT-150 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: Payment instructions are missing, rule BR-DE-1
- How to fix it
- Set up a payment method in your invoicing software, such as a bank transfer with your IBAN, and create the invoice again.
In DATEV
In DATEV Auftragswesen next, the payment means code (BT-81) comes from the payment settings in DATEV Stammdaten online (master data). The program takes the IBAN (BT-84) from DATEV Stammdaten online as well.
Vendor’s help page, retrieved 2 November 2026What the rule requires
XRechnung requires payment instructions (BG-16) on every invoice. The rule reports an error when this group is missing altogether. In files that start with Invoice or CreditNote, it is the PaymentMeans entry. In files that start with CrossIndustryInvoice, it is the SpecifiedTradeSettlementPaymentMeans entry.
- Common cause
- The invoice names no way to pay, for instance because it is already paid or the amount is being offset. Or no payment method is set up in the invoicing software.
- Details concerned
- BG-16 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The seller contact is missing, rule BR-DE-2
- How to fix it
- Enter a contact person, a telephone number and an email address in the company settings and create the invoice again.
In DATEV
In DATEV Auftragswesen next, your company’s contact person (BT-41), telephone number (BT-42) and email address (BT-43) come from configuration (“Konfiguration”), “E-Rechnung”, fields contact person (“Ansprechpartner”), telephone (“Telefon”) and email (“E-Mail”).
Vendor’s help page, retrieved 2 November 2026What the rule requires
XRechnung requires a seller contact (BG-6) on every invoice. The rule reports an error when this group is missing altogether. Once it is in the file, rules BR-DE-5 to BR-DE-7 require a contact point (BT-41), a telephone number (BT-42) and an email address (BT-43) in it.
- Common cause
- The invoicing software holds no contact person, telephone number or email address for your own company, or it leaves them out of the file.
- Details concerned
- BG-6 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The seller’s telephone number is missing, rule BR-DE-6
- How to fix it
- Enter a telephone number with at least three digits in the company settings and create the invoice again.
In DATEV
In DATEV Auftragswesen next, your company’s telephone number (BT-42) comes from configuration (“Konfiguration”), “E-Rechnung”, telephone field (“Telefon”).
Vendor’s help page, retrieved 2 November 2026What the rule requires
XRechnung requires a telephone number (BT-42) in the seller contact (BG-6). The rule reports an error when that entry is missing or holds nothing but spaces. Without a number, the check also reports BR-DE-27.
- Common cause
- The invoicing software holds no telephone number for your own company, or it leaves the number out of the file.
- Details concerned
- BT-42 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The seller’s email address is missing, rule BR-DE-7
- How to fix it
- Enter a complete email address in the company settings and create the invoice again.
In DATEV
In DATEV Auftragswesen next, your company’s email address (BT-43) comes from configuration (“Konfiguration”), “E-Rechnung”, email field (“E-Mail”).
Vendor’s help page, retrieved 2 November 2026What the rule requires
XRechnung requires an email address (BT-43) in the seller contact (BG-6). The rule reports an error when that entry is missing or holds nothing but spaces. Without an address, the check also reports BR-DE-28.
- Common cause
- The invoicing software holds no email address for your own company, or it leaves the address out of the file.
- Details concerned
- BT-43 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The seller’s telephone number has too few digits, rule BR-DE-27
- How to fix it
- Enter the full telephone number in the company settings and create the invoice again.
In DATEV
In DATEV Auftragswesen next, your company’s telephone number (BT-42) comes from configuration (“Konfiguration”), “E-Rechnung”, telephone field (“Telefon”).
Vendor’s help page, retrieved 2 November 2026What the rule requires
This XRechnung rule is a warning. The telephone number in the seller contact (BT-42) should contain at least three digits. Spaces, brackets or a plus sign may appear in between and do not count. If the number is missing altogether, error BR-DE-6 appears as well.
- Common cause
- The telephone field holds a placeholder such as a dash or a word instead of a number, or it is empty.
- Details concerned
- BT-42 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The seller’s email address is not in the usual form, rule BR-DE-28
- How to fix it
- Enter exactly one complete email address in the company settings and create the invoice again.
In DATEV
In DATEV Auftragswesen next, your company’s email address (BT-43) comes from configuration (“Konfiguration”), “E-Rechnung”, email field (“E-Mail”).
Vendor’s help page, retrieved 2 November 2026What the rule requires
This XRechnung rule is a warning. It checks the form of the email address in the seller contact (BT-43). The address should contain exactly one @ and no spaces. At least one dot should follow the @, and that part should neither start nor end with a dot. If the address is missing altogether, error BR-DE-7 appears as well.
- Common cause
- Part of the address is missing, such as the ending like .de. Or it contains a space, or the field holds two addresses.
- Details concerned
- BT-43 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The IBAN for the credit transfer does not check out, rule BR-DE-19
- How to fix it
- Compare the IBAN in your invoicing software with the details from your bank and create the invoice again.
In DATEV
DATEV Auftragswesen next takes the IBAN (BT-84) automatically from DATEV Stammdaten online (master data). It sets the payment means code (BT-81) from the payment settings there.
Vendor’s help page, retrieved 2 November 2026What the rule requires
This XRechnung rule is a warning, which on its own leaves the invoice counting as meeting the rules. It applies when the payment means code (BT-81) is 58, a SEPA credit transfer. The payment account identifier (BT-84) should then be an IBAN. The rule checks its layout of country code, two check digits and up to 30 letters or digits, and recalculates the check digits. Spaces in the IBAN do not matter to it.
- Common cause
- The IBAN contains a typo, such as two swapped digits or a missing one. Or the field holds an account number instead of an IBAN.
- Details concerned
- BT-84, BT-81 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: A line net amount does not match quantity and price, rule PEPPOL-EN16931-R120
- How to fix it
- Recalculate the amount of the line reported: quantity times net price, divided by the base quantity, plus charges, minus allowances. Use the result as the line net amount and create the invoice again. If your invoicing software calculates the amount itself, contact its vendor.
In DATEV
According to DATEV’s field list, DATEV Auftragswesen next calculates each line net amount (BT-131) automatically as quantity (BT-129) times price (BT-146).
Vendor’s help page, retrieved 2 November 2026What the rule requires
The net amount of an invoice line (BT-131) has to follow from quantity and price. The calculation is quantity (BT-129) times net price (BT-146), divided by the price base quantity (BT-149). Charges on the line are added and allowances taken off. The rule allows a difference of up to 0.02, which is 2 cents on a euro invoice. It comes from the Peppol BIS Billing 3.0 rule set. XRechnung takes it over and classifies it as a warning.
- Common cause
- Someone changed the line amount by hand, or quantity or price were adjusted afterwards without recalculating the amount. If the line total then no longer matches the lines either, the check also reports BR-CO-10.
- Details concerned
- BT-131, BT-129, BT-146, BT-149 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The seller contact point is missing, rule BR-DE-5
- How to fix it
- Enter a contact in the company settings, such as a name or a department like accounts, and create the invoice again.
In DATEV
In DATEV Auftragswesen next, your company’s contact point (BT-41) comes from configuration (“Konfiguration”), “E-Rechnung”, contact person field (“Ansprechpartner”).
Vendor’s help page, retrieved 2 November 2026What the rule requires
XRechnung requires a contact point (BT-41) in the seller contact (BG-6). This can be the name of a person or of a department. The rule reports an error when that entry is missing or holds nothing but spaces.
- Common cause
- The invoicing software holds no contact person for your own company, or it leaves the contact out of the file.
- Details concerned
- BT-41 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: Unknown VAT category code, rule BR-CL-17
- How to fix it
- Look up the value at the position reported and use the matching code from the list. Which category applies to your supply is a question for your tax advisor. If your invoicing software writes the value, contact its vendor.
In DATEV
According to DATEV’s field list, DATEV Auftragswesen next fills in the VAT category of the breakdown (BT-118) automatically from the tax rate and the exemption settings. It sets the category of an allowance (BT-95) from the tax rate.
Vendor’s help page, retrieved 2 November 2026What the rule requires
The VAT category appears in the file as a code from the UNCL 5305 list. The codes allowed are AE, L, M, E, S, Z, G, O, K and B. S, for example, stands for supplies taxed at a rate above zero. The rule reports any other value and tells upper and lower case apart. In files that start with Invoice or CreditNote, it checks the VAT breakdown (BT-118) and allowances and charges (BT-95, BT-102). In files that start with CrossIndustryInvoice, it checks allowances and charges. Rule BR-CL-18 covers the other places.
- Common cause
- The invoicing software writes a tax rate or a word instead of the code, such as 19 or Standard. Or the code is in lower case.
- Details concerned
- BT-118, BT-95, BT-102 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: A date with format 102 is written differently, rule CII-DT-097
- How to fix it
- The invoicing software writes the date when it creates the file. If it has no setting for this, send the vendor the code with the position reported.
What the rule requires
The rule applies to files that start with CrossIndustryInvoice. If a date carries the extra detail format with the value 102, it needs eight digits in the form YYYYMMDD, such as 20261102. The month has to lie between 01 and 12 and the day between 01 and 31. The rule reports a date written any other way as an error.
- Common cause
- The invoicing software writes the date with hyphens or dots, such as 2026-11-02 or 02.11.2026, or in the order day, month, year. With hyphens or dots, the check also reports BR-TMP-7 in an XRechnung.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: A date is not in the form YYYYMMDD, rule BR-TMP-7
- How to fix it
- The invoicing software writes the date when it creates the file. If it has no setting for this, send the vendor the code with the position reported.
What the rule requires
The rule applies to files that start with CrossIndustryInvoice. There, XRechnung requires every date as eight digits in the form YYYYMMDD, such as 20261102 for 2 November 2026. The date also needs the extra detail format with the value 102. The rule reports a date that lacks either. The XRechnung rule set lists it as a temporary rule and classifies it as a warning. A warning on its own leaves the invoice counting as meeting the rules.
- Common cause
- The invoicing software writes the date in another form, such as with hyphens as in 2026-11-02, or leaves out the extra detail format.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The file departs from the format’s schema, rule SCHEMA
- How to fix it
- The message gives the line and column in the XML file. For an XML file, open it in a text editor and look at the entry or value in that spot. For a PDF invoice, line and column count within the XML file embedded in the PDF, which a text editor does not show. If the invoice came straight from your invoicing software, the cause lies in the software. Send the vendor the code together with the line and column.
In DATEV
Send DATEV the code with its line and column if the file came unchanged from a DATEV program such as Auftragswesen next. DATEV takes such reports through a support request (“Servicekontakt”). You start one at the very bottom of the pages of DATEV’s help portal (“DATEV Wissensplattform”), under customer support (“Kundensupport”). This needs a DATEV login such as DATEV SmartLogin.
Vendor’s help page, retrieved 23 October 2026What the rule requires
Each invoice format has a schema, a technical template for the XML file, which is the machine-readable part of the invoice. The schema sets out which entries exist, the order they come in and the form each value takes. At the position reported, the file does not follow that template. A code with cvc-complex-type.2.4 reports an entry the format has no place for at that point, or a required entry that is missing. With cvc-complex-type.2.1 and cvc-complex-type.2.3, an entry holds text or another entry that the format does not allow there. Codes with cvc-complex-type.3 and cvc-complex-type.4 concern an extra detail attached to an entry, such as the currency on an amount. It is missing, not allowed there, or has a value other than the one required. The remaining codes, among them cvc-complex-type.2.2, cvc-datatype and cvc-pattern, usually concern a value in the wrong form, for example a date. The code names come from the XML Schema standard published by the W3C, the body that sets web standards.
- Common cause
- The software that produced the file put an entry where the format has no place for it, or left out an entry the format requires. It may also have written a value in a form the format does not accept. Editing the file by hand after it was produced can lead to the same messages.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The checking program stopped the check, rule generic-error
- How to fix it
- Create the invoice again or ask the sender for a new copy, then check the new file. If the same error comes back, send the code to the vendor of the invoicing software. You can open an XML file in a text editor and look for a lone & instead of & or a line with the word DOCTYPE. A text editor does not show the XML file inside a PDF invoice.
In DATEV
DATEV archives e-invoices from DATEV Auftragswesen next in DATEV Belege online. Open the document there and choose download original (“Original herunterladen”) under settings (“Einstellungen”). Run the check again on that copy. If it cannot be read either, contact DATEV through a support request (“Servicekontakt”, document no. 1071593).
Vendor’s help page, retrieved 23 October 2026What the rule requires
The check runs a checking program from KoSIT, Germany’s coordination office for IT standards. That program stopped the check. If it could not read the file as XML, the format used for the machine-readable part of an e-invoice, it checked none of the rules. It reports generic-error for any reading problem that has no schema code of its own starting with cvc. The check shows the same code when the program can read the file but stops at one of the rules. The other messages may then be incomplete, because some rules were never checked.
- Common cause
- The XML is incomplete because the file is cut off or damaged. Or a character such as & appears in the text, say in a company name, where the file should contain & at that point. The checking program also turns away a file when a line with the word DOCTYPE comes before its first entry. This block is a fixed setting of the checking program. The message does not say whether the file breaks the rules of its format. A rule stops, for example, when the identifier of the invoice format appears twice in the file.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: No rules for this file’s identifier, rule KEIN-SZENARIO
- How to fix it
- Look up the identifier in the file. Files that start with Invoice or CreditNote hold it in the CustomizationID entry. Files that start with CrossIndustryInvoice hold it in the ID entry under GuidelineSpecifiedDocumentContextParameter. For XRechnung 3.0 it reads urn:cen.eu:en16931:2017#compliant#urn:xeinkauf.de:kosit:xrechnung_3.0, and for a plain EN 16931 invoice urn:cen.eu:en16931:2017. For Peppol BIS Billing 3.0 it begins with urn:cen.eu:en16931:2017#compliant#urn:fdc:peppol.eu:2017:poacc:billing:3.0. A near match with a typo points to a fault in the software that produced the file.
What the rule requires
Every e-invoice carries an identifier stating which specification it follows; the EN 16931 standard numbers this detail BT-24. The check runs a checking program from KoSIT, Germany’s coordination office for IT standards, which picks the rules to apply from this identifier. It knows the identifiers for XRechnung 3.0, for Peppol BIS Billing 3.0 and for plain EN 16931 invoices. The identifier in this file matches none of them, so the program checked none of the rules.
- Common cause
- The file follows a specification the check has no rules for, for instance another format based on EN 16931 with an identifier of its own. The identifier may also be missing or contain a typo.
- Details concerned
- BT-24 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: ZUGFeRD profile MINIMUM, rule PROFIL-MINIMUM
- How to fix it
- This profile has no details for individual invoice lines and no VAT breakdown. EN 16931 requires both (rules BR-16 and BR-CO-18), and the ZUGFeRD profile EN 16931 includes them. Have the invoice produced in the EN 16931 profile or as XRechnung, either in your own invoicing software or by the sender. The check tests both.
In DATEV
When you upload a ZUGFeRD invoice in the MINIMUM profile to DATEV Unternehmen online, DATEV handles it like an ordinary PDF invoice. It reads values such as the invoice amount, number and date from the PDF part. In the invoice type filter (“Rechnungsart”) the invoice is listed as other invoice (“Sonstige Rechnung”). DATEV suggests contacting whoever issued the invoice in this case (document no. 1039353).
Vendor’s help page, retrieved 23 October 2026What the rule requires
The file’s identifier names the ZUGFeRD profile MINIMUM. A profile sets how much information the machine-readable part of a ZUGFeRD invoice carries. According to FeRD, the German forum for electronic invoicing, MINIMUM holds the main buyer and seller details, the invoice total and the total VAT. At line level it allows only the buyer’s reference, and it has no VAT breakdown. FeRD therefore describes it as an aid for bookkeeping. This check does not test the rules of this profile.
- Common cause
- The invoicing software produced the file in the MINIMUM profile.
- Details concerned
- BT-24 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: ZUGFeRD profile BASIC WL, rule PROFIL-BASICWL
- How to fix it
- This profile carries no invoice lines. EN 16931 requires at least one (rule BR-16), and the ZUGFeRD profile EN 16931 includes them. Have the invoice produced in the EN 16931 profile or as XRechnung, either in your own invoicing software or by the sender. The check tests both.
In DATEV
When you upload a ZUGFeRD invoice in the BASIC WL profile to DATEV Unternehmen online, DATEV handles it like an ordinary PDF invoice. It reads values such as the invoice amount, number and date from the PDF part. In the invoice type filter (“Rechnungsart”) the invoice is listed as other invoice (“Sonstige Rechnung”). DATEV suggests contacting whoever issued the invoice in this case (document no. 1039353).
Vendor’s help page, retrieved 23 October 2026What the rule requires
The file’s identifier names the ZUGFeRD profile BASIC WL. A profile sets how much information the machine-readable part of a ZUGFeRD invoice carries. According to FeRD, the German forum for electronic invoicing, BASIC WL has no invoice lines. At the level of the whole document it carries everything needed to book the invoice, which is why FeRD calls it an aid for bookkeeping. This check does not test the rules of this profile.
- Common cause
- The invoicing software produced the file in the BASIC WL profile.
- Details concerned
- BT-24 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: ZUGFeRD 1.0, rule PROFIL-ZUGFERD1
- How to fix it
- Have the invoice produced in the ZUGFeRD profile EN 16931 or as XRechnung, either in your own invoicing software or by the sender. The check tests both. If your software can only write version 1.0, ask the vendor about a newer release.
In DATEV
When you upload a ZUGFeRD 1.0 invoice to DATEV Unternehmen online, DATEV handles it like an ordinary PDF invoice. It reads values such as the invoice amount, number and date from the PDF part. In the invoice type filter (“Rechnungsart”) the invoice is listed as other invoice (“Sonstige Rechnung”). DATEV suggests contacting whoever issued the invoice in this case (document no. 1039353).
Vendor’s help page, retrieved 23 October 2026What the rule requires
The file is built to ZUGFeRD 1.0, as its identifier shows: it begins with urn:ferd:CrossIndustryDocument:invoice:1p0. The check has no rules for this version.
- Common cause
- The invoicing software writes ZUGFeRD in version 1.0.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: ZUGFeRD profile BASIC, rule PROFIL-BASIC
- How to fix it
- The check has not tested the details in this file, so it reports no faults in them. It can test the same invoice in the EN 16931 profile or as XRechnung, if your software or the sender can produce one.
In DATEV
DATEV counts the ZUGFeRD profile BASIC among the profiles that follow the EN 16931 standard (document no. 1080601). If you receive the invoice in DATEV Unternehmen online, DATEV runs its own check when the file is uploaded. You find the outcome in the invoice type filter (“Rechnungsart”, document no. 1039584).
Vendor’s help page, retrieved 23 October 2026What the rule requires
The file’s identifier names the ZUGFeRD profile BASIC. FeRD, the German forum for electronic invoicing, describes BASIC as a subset of the EN 16931 standard. The check recognises the profile and does not yet test its rules.
- Common cause
- The invoicing software produced the file in the BASIC profile. The check runs on a checking program from KoSIT, Germany’s coordination office for IT standards, and that program has no rules for this profile.
- Details concerned
- BT-24 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: ZUGFeRD profile EXTENDED, rule PROFIL-EXTENDED
- How to fix it
- The check has not tested the details in this file, so it reports no faults in them. It can test the same invoice in the EN 16931 profile or as XRechnung, if your software or the sender can produce one.
In DATEV
DATEV counts the ZUGFeRD profile EXTENDED among the profiles that follow the EN 16931 standard (document no. 1080601). If you receive the invoice in DATEV Unternehmen online, DATEV runs its own check when the file is uploaded. You find the outcome in the invoice type filter (“Rechnungsart”, document no. 1039584).
Vendor’s help page, retrieved 23 October 2026What the rule requires
The file’s identifier names the ZUGFeRD profile EXTENDED. FeRD, the German forum for electronic invoicing, describes EXTENDED as an extension of EN 16931 for more involved business processes. One example is an invoice covering several deliveries or delivery addresses. FeRD also states that the issuer and the recipient have to agree on exchanging EXTENDED invoices beforehand. The check recognises the profile and does not yet test its rules.
- Common cause
- The invoicing software produced the file in the EXTENDED profile. The check runs on a checking program from KoSIT, Germany’s coordination office for IT standards, and that program has no rules for this profile.
- Details concerned
- BT-24 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: Older XRechnung version, rule PROFIL-XRECHNUNG-ALT
- How to fix it
- Have the invoice produced as XRechnung 3.0, either in your own invoicing software or by the sender. If your software can only write older versions, ask the vendor about a newer release.
In DATEV
DATEV’s help (as of 8 October 2026) states that DATEV programs such as DATEV Auftragswesen next send XRechnung in version 3.0.2.
Vendor’s help page, retrieved 23 October 2026What the rule requires
The file’s identifier names an XRechnung version older than 3.0, such as 2.3. For XRechnung, this check covers version 3.0 only. KoSIT, Germany’s coordination office for IT standards and the body responsible for XRechnung, put version 3.0 into force on 1 February 2024. On the same date it withdrew version 2.3, which it no longer recommends using.
- Common cause
- The invoicing software still writes the identifier of an earlier version, or the invoice dates from before 1 February 2024.
- Details concerned
- BT-24 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: Peppol invoice starting with CrossIndustryInvoice, rule PROFIL-PEPPOL
- How to fix it
- The check has not tested the details in this file, so it reports no faults in them. It can test the same invoice as a Peppol file starting with Invoice, or as XRechnung, if your software or the sender can produce one.
In DATEV
Besides Peppol BIS Billing 3.0.20, DATEV lists XRechnung 3.0.2 and ZUGFeRD in the EN 16931 profile among the formats its programs use for sending e-invoices. The check tests those two.
Vendor’s help page, retrieved 23 October 2026What the rule requires
The file’s identifier names Peppol BIS Billing 3.0, an invoice format published by OpenPeppol and based on the EN 16931 standard. This file, however, starts with CrossIndustryInvoice. The check tests Peppol invoices only in files that start with Invoice or CreditNote.
- Common cause
- The invoicing software produced the Peppol invoice in this form. The check runs on a checking program from KoSIT, Germany’s coordination office for IT standards. That program has no rules for Peppol invoices that start with CrossIndustryInvoice.
- Details concerned
- BT-24 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: Peppol rules not loaded right now, rule PEPPOL-OHNE-REGELN
- How to fix it
- Please try again later. The check can also test the same invoice as XRechnung, if your software or the sender can produce one.
What the rule requires
The file’s identifier names Peppol BIS Billing 3.0. The check tests such invoices against the rules for Peppol invoices. Those rules are not loaded right now, so the checking program tested none of the rules and reports no faults in the file.
- Common cause
- Our server is running an older version of the checking program without the rules for Peppol invoices. This happens when an update fails.
- Details concerned
- BT-24 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The buyer reference and the order reference are both missing, rule PEPPOL-EN16931-R003
- How to fix it
- Enter the buyer reference or the purchase order number your customer gave you. One of the two is enough for this rule. If your address and your customer’s are both in Germany, rule DE-R-015 also requires the buyer reference.
What the rule requires
Peppol BIS Billing 3.0 requires the buyer reference (BT-10) or the purchase order reference (BT-13) on every invoice. The rule reports an error when both are missing.
- Common cause
- Both are missing when the customer gave neither a reference nor an order number. Or neither is entered in the invoicing software, in the customer record or the order.
- Details concerned
- BT-10, BT-13 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The buyer reference is missing, rule DE-R-015
- How to fix it
- Enter the reference your customer gave you. If you have no reference, ask your customer for one.
What the rule requires
Peppol BIS Billing 3.0 has its own rules for invoices where the seller and the buyer are both based in Germany. What counts is the country in each postal address. This rule then requires a buyer reference (BT-10). It reports an error when that entry is missing or holds nothing but spaces. XRechnung requires the same detail on every invoice, in rule BR-DE-15.
- Common cause
- This happens when the customer never supplied a reference, or when it is missing from the customer record in the invoicing software.
- Details concerned
- BT-10 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: The seller contact details are missing, rule DE-R-002
- How to fix it
- In the invoicing software, add a contact for your company with a name or department, a phone number and an email address. Then create the invoice again.
What the rule requires
Peppol BIS Billing 3.0 has its own rules for invoices where the seller and the buyer are both based in Germany. What counts is the country in each postal address. This rule then requires a contact at the seller, the group Seller contact (BG-6). It reports an error when the whole group is missing. Within it, rules DE-R-005 to DE-R-007 require a name or department, a phone number and an email address (BT-41 to BT-43).
- Common cause
- This happens when no contact person is stored for your own company in the invoicing software.
- Details concerned
- BG-6 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
: ,
We have no explanation of our own for this rule yet. Below is the checking program’s message, word for word.
Wording of the KoSIT checking program
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
Want invoices checked automatically and prepared for accounting?
In the initial call we look at how invoices reach you and which steps a program could take over. The bookkeeping itself stays with your team or your tax advisor.
Book an initial callChecked with KoSIT checking program 1.6.3 and the XRechnung configuration of 31 August 2026: XRechnung 3.0.2, XRechnung rules 2.6.0, EN 16931 rules 1.3.16. The check tests Peppol invoices with the Peppol BIS Billing 3.0.21 configuration.
Rule set versions
Checked with KoSIT checking program 1.6.3 and the XRechnung configuration of 31 August 2026: XRechnung 3.0.2, XRechnung rules 2.6.0, EN 16931 rules 1.3.16. The check tests Peppol invoices with the Peppol BIS Billing 3.0.21 configuration.
Result for an XRechnung with no buyer reference.
This is how the check shows a test invoice without a buyer reference. Every finding sits in one of six groups, and each group comes with a general note and its source.
File structure
Germany’s Federal Ministry of Finance (BMF) calls it a format error when a file does not meet the technical requirements of its format. For VAT purposes such a file counts as an “other invoice in another electronic format” (“sonstige Rechnung”). The kind of format error makes no difference (BMF letter of 15 October 2025, para. 6a). Source, retrieved 23 October 2026
EN 16931 rules
If the check reports an error against an EN 16931 rule, the file technically no longer counts as an invoice under that standard. Germany’s Federal Ministry of Finance (BMF) says this technical view does not decide VAT questions. Without a format error, the file is in principle still an e-invoice under section 14 of the German VAT Act, UStG (BMF, 15 October 2026, paras. 22–23). For the BMF, an error can only be a content error if it concerns a detail that VAT law requires on invoices (BMF, 15 October 2026, para. 22, and 15 October 2025, para. 35a). Whether that applies to your invoice is for your tax advisor to judge. Source, retrieved 23 October 2026 Further source, retrieved 23 October 2026
XRechnung rules
These rules belong to the XRechnung rule set and go further than the EN 16931 standard. For VAT purposes, any format that follows this standard is permitted (VAT Application Decree, UStAE, section 14.1(11)). Which one applies is for you to agree with your customer or supplier (section 14.1(12)). For Germany’s Federal Ministry of Finance (BMF), a rule error can only be a content error if it concerns a required invoice detail under VAT law (BMF, 15 October 2026, para. 22). Whether that applies to your invoice is for your tax advisor to judge. For invoices to public authorities and other public contracting bodies, further rules apply alongside VAT law, such as the federal E-Invoicing Ordinance (E-Rechnungsverordnung; paras. 24 and 25). Source, retrieved 23 October 2026 Further source, retrieved 23 October 2026
Peppol BIS Billing 3.0 rules
These rules belong to the Peppol BIS Billing 3.0 rule set and go further than the EN 16931 standard. For VAT purposes, any format that follows this standard is permitted, even one that does not come from Germany (VAT Application Decree, UStAE, sections 14.1(11) and 14.1(12)). Which one applies is for you to agree with your customer or supplier (section 14.1(12)). For Germany’s Federal Ministry of Finance (BMF), a rule error can only be a content error if it concerns a required invoice detail under VAT law (BMF, 15 October 2026, para. 22). Whether that applies to your invoice is for your tax advisor to judge. Source, retrieved 23 October 2026 Further source, retrieved 23 October 2026
ZUGFeRD profile
Germany’s Federal Ministry of Finance counts ZUGFeRD from version 2.0.1 among the permitted e-invoice formats, except the MINIMUM and BASIC WL profiles (UStAE section 14.1(14)). Source, retrieved 23 October 2026
Outside this check
This check does not cover this version or format. It covers XRechnung 3.0 and invoices that follow the EN 16931 standard without additions. For Peppol BIS Billing 3.0, it checks files that start with Invoice or CreditNote.
The file does not meet all the rules we checked.
1 error, 1 note XRechnung 3.0
XRechnung rules
These rules belong to the XRechnung rule set and go further than the EN 16931 standard.
What this means
These rules belong to the XRechnung rule set and go further than the EN 16931 standard. For VAT purposes, any format that follows this standard is permitted (VAT Application Decree, UStAE, section 14.1(11)). Which one applies is for you to agree with your customer or supplier (section 14.1(12)). For Germany’s Federal Ministry of Finance (BMF), a rule error can only be a content error if it concerns a required invoice detail under VAT law (BMF, 15 October 2026, para. 22). Whether that applies to your invoice is for your tax advisor to judge. For invoices to public authorities and other public contracting bodies, further rules apply alongside VAT law, such as the federal E-Invoicing Ordinance (E-Rechnungsverordnung; paras. 24 and 25). Source, retrieved 23 October 2026 Further source, retrieved 23 October 2026
Error: The buyer reference is missing, rule BR-DE-15
- How to fix it
- Enter the reference your customer gave you. For German federal authorities this is the Leitweg-ID, which the authority states with its order. If you have no reference, ask your customer for one.
- VAT, in general
- Germany’s Federal Ministry of Finance cites a missing buyer reference (BT-10) as an example of a rule error that does not matter for VAT. Whether your customer needs the entry anyway depends on your agreement with them. Invoices to German federal authorities need the Leitweg-ID in this field (section 5 of the federal E-Invoicing Ordinance, E-Rechnungsverordnung; BMF, 15 October 2026, paras. 24 and 25). Source, retrieved 23 October 2026
In Lexware Office
Lexware Office keeps the Leitweg-ID on the customer record, under contacts (“Kontakte”), edit contact (“Kontakt bearbeiten”), section “E-Rechnung”, field “Leitweg ID”. First check that Lexware Office created the invoice as an XRechnung. Once the ID is in place, open the invoice for editing, save it and download the XML file again.
Vendor’s help page, retrieved 23 October 2026In sevdesk
sevdesk calls the buyer reference “Kundenreferenz / Leitweg-ID”. The field sits in the lower part of the invoice form under “Weitere Optionen”. If the Leitweg-ID belongs on every invoice to this customer, switch on “E-Rechnung Standard” in the contact and enter it there. According to the help page, sevdesk writes 0 as the customer reference when you leave the field empty.
Vendor’s help page, retrieved 23 October 2026In DATEV
In DATEV Auftragswesen next, the buyer reference belongs in the customer record, in the customer reference field (“Kundenreferenz”). A public authority’s Leitweg-ID goes there too. The program uses the field once “E-Rechnung” is selected as the invoice format under general invoice data (“Allgemeine Rechnungsdaten”) for that customer. The field also decides how the invoice is sent. Without an entry, it goes out by email as ZUGFeRD. With a TRAFFIQX ID (prefixed “TX:”) or a Leitweg-ID, it goes through a portal, provided the recipient is registered there. For an invoice that is still a draft, select the customer in it again so the draft picks up the changed details. DATEV E-Rechnungsschreibung calls the same field “Leitweg-ID/ Kundenreferenz” (document no. 1028945).
Vendor’s help page, retrieved 23 October 2026What the rule requires
XRechnung requires a buyer reference (BT-10) on every invoice. The rule reports an error when that entry is missing or holds nothing but spaces. EN 16931 lists the buyer reference as optional; this XRechnung rule makes it mandatory.
- Common cause
- This happens when the customer never supplied a reference, or when it is missing from the customer record in the invoicing software.
- Details concerned
- BT-10 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
-
/Invoice[1]
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
Note: No delivery date or service period, rule BR-DE-TMP-32
- How to fix it
- Add the delivery date or an invoicing period for the whole invoice. If you prefer periods per line, give every line one, including minor items such as shipping.
- VAT, in general
- The German VAT Act lists the date of the supply of goods or services as a required invoice detail (section 14(4) sentence 1 no. 6 UStG). A mapping table by KoSIT, Germany’s coordination office for IT standards, and FeRD, the German e-invoicing forum, puts it in BT-72, BG-14 and BG-26. Germany’s Federal Ministry of Finance (BMF) recommends basing e-invoices on this table (BMF, 15 October 2026, paras. 8 and 9). According to the BMF, every required detail belongs in the machine-readable part of an e-invoice (BMF, 15 October 2025, para. 35). Source, retrieved 23 October 2026
In Lexware Office
In the Lexware Office invoice editor the date sits in the customer details (“Kundenangaben”), in the delivery date field (“Lieferdatum”). Switch that field to service period (“Leistungszeitraum”) and enter a start and end date, or to service date (“Leistungsdatum”) for a single day. Lexware asks for the service period on e-invoices.
Vendor’s help page, retrieved 23 October 2026In sevdesk
The sevdesk invoice form has a “Lieferdatum” (delivery date) field. To have it filled in on every new invoice, turn on “Lieferdatum automatisch setzen” under “Einstellungen”, “System”, “Aufträge & Rechnungen”. The help page leaves open which date sevdesk enters, so look at it before you send the invoice.
Vendor’s help page, retrieved 23 October 2026In DATEV
In DATEV Auftragswesen next, the date goes into the date of supply field (“Liefer- & Leistungsdatum”) while you edit the invoice. Clicking the icon that belongs to it switches the field to period of supply (“Liefer- & Leistungszeitraum”), where you enter a period instead. According to DATEV’s help, Auftragswesen next will not save the invoice while this field is empty.
Vendor’s help page, retrieved 23 October 2026What the rule requires
XRechnung recommends that the invoice states when goods were delivered or services performed. One of these is enough: the delivery date (BT-72), an invoicing period for the whole invoice (BG-14) or a period on each line (BG-26). The XRechnung rule set classifies this rule as a notice.
- Common cause
- The invoice lacks both a delivery date and an invoicing period. The notice also appears when only some lines carry a period, for example when a shipping line has none.
- Details concerned
- BT-72, BG-14, BG-26 EN 16931 gives every detail of an e-invoice a number, such as BT-10 for the buyer reference. BG numbers stand for groups of details.
Where in the file
The path leads from the outside in to the entry in the XML file that the rule reports.
-
/Invoice[1]
The button opens chatgpt.com in a new tab with a question about this rule. The question holds only the code and, where we have one, our explanation, nothing from your invoice. OpenAI receives it when you click. Technical explanation, not tax advice
Product names mentioned here, including OpenAI’s ChatGPT, are trademarks of their respective owners. We are not a partner of these companies.
Before you upload.
Which files does the check cover?
The check covers XRechnung files, Peppol invoices and other invoices that follow the EN 16931 standard. You upload an XML file up to about 2.1 MB or a PDF up to about 5.2 MB with an XML file inside, as in ZUGFeRD. The XML file is the part of an e-invoice that invoicing software reads. The check recognises ZUGFeRD profiles other than EN 16931, ZUGFeRD 1.0 and older XRechnung versions. For these, the result says that it does not test their rules.
What happens to my file?
Your browser sends the file to our server in Germany only when you click “Check invoice”. KoSIT’s checking program tests it there, usually in under a second. The file stays in working memory only, and we don’t store it. Your browser does not even send the file name. Each day we count which rules were broken how often, without names, amounts or invoice numbers. Section 8 of our privacy policy has the details.
What does the check not cover?
Whether the invoice is right for tax purposes, such as the VAT rate and the required details, is for your tax advisor to judge. For a PDF the check only tests the embedded XML file. It does not look at the visible part or at how the PDF itself is built. It does not yet test the specific rules of the ZUGFeRD profiles BASIC and EXTENDED.
How often can I check?
You can check up to 20 files an hour and 50 a day, free and without signing up. All visitors together share a limit of 2,000 checks a day. If the checking program cannot be reached, the attempt does not count.
We answer questions about the check in the chat.
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