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9 fatal errors

UBL syntax · Peppol BIS Billing 3.0 (+ national rules)

fatalBR-CO-17

VAT category tax amount (BT-117) = VAT category taxable amount (BT-116) x (VAT category rate (BT-119) / 100), rounded to two decimals.

WhyIn a VAT breakdown group the VAT category tax amount (BT-117) does not equal the taxable amount (BT-116) multiplied by the rate (BT-119), rounded to 2 decimals.

How to fixSet BT-117 = round(BT-116 x BT-119 / 100, 2) per breakdown group. Round the product itself with half-up rounding - summing per-line VAT amounts drifts by a cent or two. BT-119 is a percentage (21, not 0.21). Note the EN core rule tolerates a deviation of up to 1.00 in the invoice currency, so if this fires your figure is off by more than a rounding cent - look for a wrong rate or a taxable amount that excludes an allowance. National profiles (XRechnung, Peppol BIS, KSeF) routinely tighten this to the exact cent.

  24     <cbc:TaxAmount currencyID="EUR">66.66</cbc:TaxAmount>
  25     <cac:TaxSubtotal>
  26       <cbc:TaxableAmount currencyID="EUR">333.30</cbc:TaxableAmount>

line 25 · /Invoice/TaxTotal/TaxSubtotal

fatalBR-S-09

The VAT category tax amount (BT-117) in a VAT breakdown (BG-23) where VAT category code (BT-118) is "Standard rated" shall equal the VAT category taxable amount (BT-116) multiplied by the VAT category rate (BT-119).

WhyIn the VAT breakdown group for standard rated VAT (category S), the VAT category tax amount (BT-117) does not equal the taxable amount (BT-116) times the rate (BT-119).

How to fixSet BT-117 = round(BT-116 x BT-119 / 100, 2) for the S group. This rule usually fires together with BR-CO-17 - fix the arithmetic once and both clear. If BT-116 itself is wrong, fix that first (see BR-S-08), because BT-117 is derived from it.

  27       <cbc:TaxAmount currencyID="EUR">66.66</cbc:TaxAmount>
  28       <cac:TaxCategory><cbc:ID>S</cbc:ID><cbc:Percent>22</cbc:Percent><cac:TaxScheme><cbc:ID>VAT</cbc:ID></cac:TaxScheme></cac:TaxCategory>
  29     </cac:TaxSubtotal>

line 28 · /Invoice/TaxTotal/TaxSubtotal/TaxCategory

fatalPEPPOL-EN16931-R001

Business process MUST be provided.

WhyThe business process identifier (BT-23) is missing. Peppol routes on it, so an invoice without it cannot be delivered even though it is valid EN 16931.

How to fixAdd BT-23 (UBL cbc:ProfileID) with the value urn:fdc:peppol.eu:2017:poacc:billing:01:1.0 for a normal invoice-only process. This is the field most often missing when a working EN 16931 file first meets Peppol.

   3          xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2"
   4          xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2">
   5   <cbc:CustomizationID>urn:cen.eu:en16931:2017</cbc:CustomizationID>

line 4 · /Invoice

fatalPEPPOL-EN16931-R007

Business process MUST be in the format 'urn:fdc:peppol.eu:2017:poacc:billing:NN:1.0' where NN indicates the process number.

WhyThe business process identifier (BT-23) does not match the required pattern.

How to fixIt must look like urn:fdc:peppol.eu:2017:poacc:billing:NN:1.0 where NN is the two-digit process number - 01 for invoice only. A missing leading zero fails.

   3          xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2"
   4          xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2">
   5   <cbc:CustomizationID>urn:cen.eu:en16931:2017</cbc:CustomizationID>

line 4 · /Invoice

fatalPEPPOL-EN16931-R003

A buyer reference or purchase order reference MUST be provided.

WhyNeither a buyer reference (BT-10) nor a purchase order reference (BT-13) is given. Peppol needs at least one so the receiver's system can match the invoice.

How to fixAdd BT-10 (UBL cbc:BuyerReference) or BT-13 (OrderReference/cbc:ID). If the buyer gave you a reference, cost centre or Leitweg-ID, that is BT-10; if you are invoicing against a purchase order, that is BT-13.

   3          xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2"
   4          xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2">
   5   <cbc:CustomizationID>urn:cen.eu:en16931:2017</cbc:CustomizationID>

line 4 · /Invoice

fatalPEPPOL-EN16931-R004

Specification identifier MUST have the value 'urn:cen.eu:en16931:2017#compliant#urn:fdc:peppol.eu:2017:poacc:billing:3.0'.

WhyThe specification identifier (BT-24) is not the Peppol BIS Billing 3.0 customisation ID, so the receiver will not apply the Peppol rules.

How to fixSet BT-24 to exactly urn:cen.eu:en16931:2017#compliant#urn:fdc:peppol.eu:2017:poacc:billing:3.0 (the plain urn:cen.eu:en16931:2017 is not enough for Peppol).

   3          xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2"
   4          xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2">
   5   <cbc:CustomizationID>urn:cen.eu:en16931:2017</cbc:CustomizationID>

line 4 · /Invoice

fatalPEPPOL-EN16931-R020

Seller electronic address MUST be provided

WhyThe seller electronic address (BT-34) is missing.

How to fixAdd BT-34 with its EAS schemeID under AccountingSupplierParty/Party/cbc:EndpointID. It is your own Peppol address.

  10   <cbc:DocumentCurrencyCode>EUR</cbc:DocumentCurrencyCode>
  11   <cac:AccountingSupplierParty><cac:Party>
  12     <cac:PostalAddress><cac:Country><cbc:IdentificationCode>SI</cbc:IdentificationCode></cac:Country></cac:PostalAddress>

line 11 · /Invoice/AccountingSupplierParty/Party

fatalPEPPOL-EN16931-R010

Buyer electronic address MUST be provided

WhyThe buyer electronic address (BT-49) is missing. This is the Peppol routing address; without it the invoice cannot be delivered.

How to fixAdd BT-49 with its schemeID from the EAS code list - UBL AccountingCustomerParty/Party/cbc:EndpointID schemeID="0208". The buyer tells you this value; you cannot invent it.

  15   </cac:Party></cac:AccountingSupplierParty>
  16   <cac:AccountingCustomerParty><cac:Party>
  17     <cac:PostalAddress><cac:Country><cbc:IdentificationCode>DE</cbc:IdentificationCode></cac:Country></cac:PostalAddress>

line 16 · /Invoice/AccountingCustomerParty/Party

fatalPEPPOL-EN16931-R120

Invoice line net amount MUST equal (Invoiced quantity * (Item net price/item price base quantity) + Sum of invoice line charge amount - sum of invoice line allowance amount

WhyThe invoice line net amount (BT-131) does not equal quantity x (net price / base quantity), plus line charges, minus line allowances.

How to fixRecompute BT-131 = round(BT-129 x BT-146 / BT-149, 2) + line charges - line allowances, with BT-149 (base quantity) treated as 1 when absent. Peppol enforces this arithmetic per line; plain EN 16931 does not, which is why an invoice can pass one and fail the other.

  36   </cac:LegalMonetaryTotal>
  37   <cac:InvoiceLine>
  38     <cbc:ID>1</cbc:ID>

line 37 · /Invoice/InvoiceLine

1,722 rules explained

Every EN 16931 and Peppol BIS rule has its own reference page with the cause and the fix.

Hybrid PDFs, wrapper included

Factur-X and ZUGFeRD PDFs are unpacked and the XML checked — plus the container itself: /AF, /AFRelationship and the XMP profile declaration, which almost nothing else looks at.

Profiles that actually reject you

An invoice can be valid EN 16931 and still bounce off Peppol or XRechnung. The Peppol check adds the national rules for DE, DK, GR, IS, IT, NL, NO and SE automatically, from the seller's country.

Checked against the official corpus

Passes 1,142 of 1,142 assertions in CEN's own EN 16931 test suite — the same corpus the standard is validated with.

Who must comply, and when

Country-by-country mandate deadlines — Belgium, Poland, France, Germany, Slovenia and the rest.