EN 16931 Validation Rules
Reference for the EN 16931 business rules checked on Peppol BIS, UBL and Factur-X e-invoices.
EN 16931 validation rules
EN 16931 is the European standard for electronic invoicing. Its business rules (BR-*, BR-CO-*, BR-DEC-*, BR-CL-* and VAT category rules) define what a compliant Peppol BIS, UBL, XRechnung or Factur-X invoice must contain. This reference explains all 176 rules and how to fix an invoice that fails each one.
Each rule below is enforced when validating an electronic invoice against EN 16931. Click a rule to see what it checks and how to fix a file that fails it. This is a growing reference - start with our free validators to test your own file.
Mandatory fields
BR-01Specification identifier is requiredBR-02Invoice number is requiredBR-03Invoice issue date is requiredBR-04Invoice type code is requiredBR-05Invoice currency code is requiredBR-06Seller name is requiredBR-07Buyer name is requiredBR-08Seller postal address is requiredBR-09Seller country code is requiredBR-10Buyer postal address is requiredBR-11Buyer country code is requiredBR-16At least one invoice line is requiredBR-CO-19Invoicing period needs a dateBR-CO-04Each invoice line needs a VAT category codeBR-CO-09VAT identifiers need a country prefixBR-CO-20Invoice line period needs a dateBR-CO-26The seller must be identifiableBR-56Tax representative needs a VAT identifierBR-57Deliver-to address needs a country codeBR-62Seller electronic address needs a schemeBR-63Buyer electronic address needs a schemeBR-17Payee name required if Payee differs from SellerBR-18Seller tax representative VAT identifier is requiredBR-19Seller tax representative postal address is requiredBR-20Seller tax representative country code is requiredBR-CO-03VAT point date and its code are mutually exclusivePEPPOL-EN16931-R002Only one document level note is allowedPeppol BIS 3.0PEPPOL-EN16931-R008The document must not contain empty elementsPeppol BIS 3.0PEPPOL-EN16931-R010The buyer electronic address is mandatoryPeppol BIS 3.0PEPPOL-EN16931-R020The seller electronic address is mandatoryPeppol BIS 3.0BR-DE-2Mandatory: seller contact (BG-6)XRechnungBR-DE-3Mandatory: seller city (BT-37)XRechnungBR-DE-4Mandatory: seller post code (BT-38)XRechnungBR-DE-5Mandatory: seller contact point (BT-41)XRechnungBR-DE-6Mandatory: seller phone (BT-42)XRechnungBR-DE-7Mandatory: seller e-mail (BT-43)XRechnungBR-DE-8Mandatory: buyer city (BT-52)XRechnungBR-DE-9Mandatory: buyer post code (BT-53)XRechnungBR-DE-10Mandatory: deliver to city (BT-77)XRechnungBR-DE-11Mandatory: deliver to post code (BT-78)XRechnungBR-DE-15Mandatory: buyer reference (BT-10)XRechnungBR-DE-27Seller phone number should contain at least 3 digitsXRechnungBR-DE-28Seller e-mail address should be well formedXRechnungBR-DE-TMP-32The delivery date or period should be statedXRechnung
Mandatory totals
Calculations
BR-CO-10Sum of line net amounts must equal the line totalBR-CO-13Total without VAT must reconcile lines, allowances and chargesBR-CO-15Total with VAT must equal total without VAT plus VATBR-CO-16Amount due must equal total with VAT minus prepaidBR-CO-11Sum of document-level allowancesBR-CO-12Sum of document-level chargesBR-CO-14Total VAT = sum of VAT breakdownsBR-CO-17VAT amount = taxable × rateBR-29Invoicing period end must not precede its startBR-30Invoice line period end must not precede its startPEPPOL-EN16931-R051All amounts must carry the invoice currencyPeppol BIS 3.0PEPPOL-EN16931-R120The line net amount must match the line calculationPeppol BIS 3.0BR-DEX-02Line net amount must equal the sum of its sub-linesXRechnungBR-DEX-09Amount due must include third party paymentsXRechnung
VAT - Standard rated
BR-S-01A standard-rated line needs a standard-rated VAT breakdownBR-S-02Standard rated: seller tax ID requiredBR-S-03Standard rated (allowance): seller tax ID requiredBR-S-04Standard rated (charge): seller tax ID requiredBR-S-05Standard rated: line VAT rate must be positiveBR-S-06Standard rated (allowance): VAT rate must be positiveBR-S-07Standard rated (charge): VAT rate must be positiveBR-S-08Standard rated: taxable amount must match the linesBR-S-09Standard rated VAT rate must be above zeroBR-S-10Standard rated breakdown must not state an exemption reason
VAT - Zero rated
BR-Z-01Zero rated line needs a zero rated breakdownBR-Z-02Zero rated: seller tax ID requiredBR-Z-03Zero rated (allowance): seller tax ID requiredBR-Z-04Zero rated (charge): seller tax ID requiredBR-Z-05Zero rated: line VAT rate must be zeroBR-Z-06Zero rated (allowance): VAT rate must be zeroBR-Z-07Zero rated (charge): VAT rate must be zeroBR-Z-08Zero rated: taxable amount must match the linesBR-Z-09Zero rated: VAT category amount must be zeroBR-Z-10Zero rated breakdown must not state an exemption reason
VAT - Exempt
BR-E-01Exempt line needs an exempt VAT breakdownBR-E-02Exempt: seller tax ID requiredBR-E-05Exempt: line VAT rate must be zeroBR-E-09Exempt: VAT category amount must be zeroBR-E-10Exempt: exemption reason requiredBR-E-03Exempt (allowance): seller tax ID requiredBR-E-04Exempt (charge): seller tax ID requiredBR-E-06Exempt (allowance): VAT rate must be zeroBR-E-07Exempt (charge): VAT rate must be zeroBR-E-08Exempt: taxable amount must match the linesPEPPOL-EN16931-P0108Exemption code VATEX-EU-D requires VAT category EPeppol BIS 3.0PEPPOL-EN16931-P0109Exemption code VATEX-EU-F requires VAT category EPeppol BIS 3.0PEPPOL-EN16931-P0110Exemption code VATEX-EU-I requires VAT category EPeppol BIS 3.0PEPPOL-EN16931-P0111Exemption code VATEX-EU-J requires VAT category EPeppol BIS 3.0
VAT - Reverse charge
BR-AE-01Reverse charge line needs an AE VAT breakdownBR-AE-08Reverse charge taxable amount must match the linesBR-AE-02Reverse charge: seller & buyer tax ID requiredBR-AE-03Reverse charge (allowance): seller & buyer tax ID requiredBR-AE-04Reverse charge (charge): seller & buyer tax ID requiredBR-AE-05Reverse charge: line VAT rate must be zeroBR-AE-06Reverse charge (allowance): VAT rate must be zeroBR-AE-07Reverse charge (charge): VAT rate must be zeroBR-AE-09Reverse charge: VAT category amount must be zeroBR-AE-10Reverse charge: exemption reason requiredPEPPOL-EN16931-P0107Exemption code VATEX-EU-AE requires VAT category AEPeppol BIS 3.0
Decimals
BR-DEC-23Line net amount: max 2 decimalsBR-DEC-12Total without VAT: max 2 decimalsBR-DEC-14Total with VAT: max 2 decimalsBR-DEC-01Document allowance amount: max 2 decimalsBR-DEC-02Document allowance base amount: max 2 decimalsBR-DEC-05Document charge amount: max 2 decimalsBR-DEC-06Document charge base amount: max 2 decimalsBR-DEC-09Sum of line net amounts: max 2 decimalsBR-DEC-10Sum of document allowances: max 2 decimalsBR-DEC-11Sum of document charges: max 2 decimalsBR-DEC-13Total VAT amount: max 2 decimalsBR-DEC-15Total VAT in accounting currency: max 2 decimalsBR-DEC-16Paid amount: max 2 decimalsBR-DEC-17Rounding amount: max 2 decimalsBR-DEC-18Amount due for payment: max 2 decimalsBR-DEC-19VAT category taxable amount: max 2 decimalsBR-DEC-20VAT category tax amount: max 2 decimalsBR-DEC-24Line allowance amount: max 2 decimalsBR-DEC-25Line allowance base amount: max 2 decimalsBR-DEC-27Line charge amount: max 2 decimalsBR-DEC-28Line charge base amount: max 2 decimalsPEPPOL-EN16931-F001Dates must use the YYYY-MM-DD formatPeppol BIS 3.0BR-DEX-13Third party payment amount: at most two decimalsXRechnung
VAT - Intra-community
BR-IC-01Intra-community: exactly one VAT breakdownBR-IC-02Intra-community: seller & buyer VAT ID requiredBR-IC-05Intra-community: line VAT rate must be zeroBR-IC-10Intra-community: exemption reason requiredBR-IC-11Intra-community: delivery date or period requiredBR-IC-03Intra-community (allowance): seller & buyer VAT ID requiredBR-IC-04Intra-community (charge): seller & buyer VAT ID requiredBR-IC-06Intra-community (allowance): VAT rate must be zeroBR-IC-07Intra-community (charge): VAT rate must be zeroBR-IC-08Intra-community: taxable amount must match the linesBR-IC-09Intra-community: VAT category amount must be zeroBR-IC-12Intra-community: deliver-to country requiredPEPPOL-EN16931-P0106Exemption code VATEX-EU-IC requires VAT category KPeppol BIS 3.0
VAT - Export outside the EU
BR-G-01Export outside the EU: exactly one VAT breakdownBR-G-02Export outside the EU: seller tax ID requiredBR-G-05Export outside the EU: line VAT rate must be zeroBR-G-09Export outside the EU: VAT category amount must be zeroBR-G-10Export outside the EU: exemption reason requiredBR-G-03Export outside the EU (allowance): seller tax ID requiredBR-G-04Export outside the EU (charge): seller tax ID requiredBR-G-06Export outside the EU (allowance): VAT rate must be zeroBR-G-07Export outside the EU (charge): VAT rate must be zeroBR-G-08Export outside the EU: taxable amount must match the linesPEPPOL-EN16931-P0104Exemption code VATEX-EU-G requires VAT category GPeppol BIS 3.0
VAT - Not subject
BR-O-01Not subject to VAT: exactly one VAT breakdownBR-O-02Not subject to VAT: category cannot be mixedBR-O-03Not subject to VAT limits use of Seller VAT identifierBR-O-04Not subject to VAT line must not carry Buyer VAT identifierBR-O-05Not subject to VAT line must not carry an item VAT rateBR-O-06Not subject to VAT allowance must not carry a VAT rateBR-O-07Not subject to VAT charge must not carry a VAT rateBR-O-08Not subject to VAT taxable amount must match its linesBR-O-09Not subject to VAT category tax amount must be zeroBR-O-10Not subject to VAT breakdown must state an exemption reasonBR-O-11Not subject to VAT excludes other VAT breakdownsBR-O-12Not subject to VAT excludes other categories on contentBR-O-13Not subject to VAT: allowances must all be OBR-O-14Not subject to VAT: charges must all be OPEPPOL-EN16931-P0105Exemption code VATEX-EU-O requires VAT category OPeppol BIS 3.0
Allowances & charges
BR-CO-05Allowance reason code and text must agreeBR-CO-06Charge reason code and text must agreeBR-CO-21Each allowance needs a reasonBR-CO-22Each charge needs a reasonBR-31Each document-level allowance needs an amountBR-32Each document-level allowance needs a VAT category codeBR-36Each document-level charge needs an amountBR-37Each document-level charge needs a VAT category codeBR-41Each invoice line allowance needs an amountBR-43Each invoice line charge needs an amountBR-CO-23Each invoice line allowance needs a reasonBR-CO-24Each invoice line charge needs a reasonBR-33Document-level allowance must state a reasonBR-38Document-level charge must state a reasonBR-42Line-level allowance must state a reasonBR-44Line-level charge must state a reasonBR-CO-07Line allowance reason code and text must agreeBR-CO-08Line charge reason code and text must agreeBR-AF-01Document charge must have a VAT category codeBR-AF-04Document charge VAT category code must be validBR-AF-07Exempt document charge rate must be zeroBR-AF-08Reverse charge document charge rate must be zeroBR-AG-01Document allowance must have a VAT category codeBR-AG-03Document allowance must state a reasonBR-AG-06Zero-rated document allowance rate must be zeroBR-AG-08Reverse charge document allowance rate must be zeroPEPPOL-EN16931-R040Allowance or charge must equal base times percentagePeppol BIS 3.0PEPPOL-EN16931-R041A percentage requires a base amountPeppol BIS 3.0PEPPOL-EN16931-R042A base amount requires a percentagePeppol BIS 3.0PEPPOL-EN16931-R043The charge indicator must be true or falsePeppol BIS 3.0PEPPOL-EN16931-R044No charge is allowed at item price levelPeppol BIS 3.0PEPPOL-EN16931-R046Net price must equal gross price minus the price discountPeppol BIS 3.0
Payment
BR-CO-25Amount due needs a due date or payment termsBR-49Payment instruction needs a means type codeBR-50Credit transfer needs an account identifierBR-51Never include a full card numberBR-61Credit-transfer means needs an account identifierPEPPOL-EN16931-R061A direct debit requires a mandate referencePeppol BIS 3.0BR-DE-1Mandatory: payment instructions (BG-16)XRechnungBR-DE-18Cash discount must follow the SKONTO format in BT-20XRechnungBR-DE-19BT-84 must be a valid IBAN for SEPA credit transferXRechnungBR-DE-20BT-91 must be a valid IBAN for SEPA direct debitXRechnungBR-DE-23Only one credit transfer account is allowedXRechnungBR-DE-24Only one payment card group is allowedXRechnungBR-DE-25Only one direct debit group is allowedXRechnungBR-DE-30Direct debit requires the creditor identifier (BT-90)XRechnungBR-DE-31Direct debit requires the debited account (BT-91)XRechnungBR-DEX-10Mandatory: third party payment type (BT-DEX-001)XRechnungBR-DEX-11Mandatory: third party payment amount (BT-DEX-002)XRechnungBR-DEX-12Mandatory: third party payment description (BT-DEX-003)XRechnungBR-DEX-14Third party payment must use the invoice currencyXRechnung
Invoice lines
BR-21Each invoice line needs an identifierBR-22Each invoice line needs a quantityBR-23Each invoice line needs a unit of measureBR-24Each invoice line needs a net amountBR-25Each invoice line needs an item nameBR-26Each invoice line needs a net priceBR-27Item net price must not be negativeBR-28Item gross price must not be negativeBR-54Item attribute needs a name and a valueBR-64Item standard identifier needs a schemeBR-65Item classification identifier needs a schemePEPPOL-EN16931-R110The line period must start within the invoice periodPeppol BIS 3.0PEPPOL-EN16931-R111The line period must end within the invoice periodPeppol BIS 3.0PEPPOL-EN16931-R121The price base quantity must be strictly positivePeppol BIS 3.0PEPPOL-EN16931-R130Price base quantity must use the invoiced unitPeppol BIS 3.0BR-DEX-03A sub invoice line needs exactly one VAT blockXRechnungBR-DEX-15Extension recommendation on a line description fieldXRechnungBR-DE-CVD-03A CVD line with vehicle category and cva is requiredXRechnung
VAT breakdown
BR-45Each VAT breakdown needs a taxable amountBR-46Each VAT breakdown needs a tax amountBR-47Each VAT breakdown needs a category codeBR-48Each VAT breakdown needs a rate (unless not subject to VAT)BR-B-01Standard rated cannot be mixed with certain categoriesBR-B-02Standard rated cannot be mixed with certain categoriesBR-AF-02IGIC line requires a Seller tax identifierBR-AF-03IGIC document allowance needs a Seller tax IDBR-AF-05IGIC line VAT rate must be zero or greaterBR-AF-06IGIC document allowance rate: zero or greaterBR-AF-09IGIC VAT amount = taxable amount x rateBR-AF-10IGIC breakdown must carry no exemption reasonBR-AG-02IPSI line requires a Seller tax identifierBR-AG-04IPSI document charge needs a Seller tax IDBR-AG-05IPSI line VAT rate must be zero or greaterBR-AG-07IPSI document charge rate: zero or greaterBR-AG-09IPSI VAT amount = taxable amount x rateBR-AG-10IPSI breakdown must carry no exemption reasonPEPPOL-EN16931-R005VAT accounting currency must differ from invoice currencyPeppol BIS 3.0PEPPOL-EN16931-R053Only one tax total may carry the VAT breakdownPeppol BIS 3.0PEPPOL-EN16931-R054One tax total without breakdown when a tax currency existsPeppol BIS 3.0PEPPOL-EN16931-R055The two total VAT amounts must have the same signPeppol BIS 3.0BR-DE-14Mandatory: VAT category rate (BT-119)XRechnungBR-DE-16Seller tax identification requiredXRechnung
References
BR-52Each supporting document needs a referenceBR-55Each preceding invoice reference needs a numberPEPPOL-EN16931-R003A buyer reference or a purchase order reference is requiredPeppol BIS 3.0PEPPOL-EN16931-R080Only one project reference at document levelPeppol BIS 3.0PEPPOL-EN16931-R100Only one invoiced object identifier per linePeppol BIS 3.0PEPPOL-EN16931-R101Line document reference must be the invoiced objectPeppol BIS 3.0BR-DE-21Specification identifier should be the XRechnung oneXRechnungBR-DE-22Attachment file names must be uniqueXRechnungBR-DE-26Corrected invoice (384) should reference the originalXRechnungBR-DE-CVD-01Mandatory: contract reference (BT-12)XRechnungBR-DE-CVD-02Mandatory: tender or lot reference (BT-17)XRechnung
Code lists
BR-CL-01Invoice type code: UNTDID 1001BR-CL-03Amount currency (@currencyID): ISO 4217BR-CL-04Invoice currency code: ISO 4217BR-CL-05VAT accounting currency code: ISO 4217BR-CL-06VAT point date code: UNTDID 2005BR-CL-07Object identifier scheme: UNTDID 1153BR-CL-08Invoice note subject code: UNCL 4451BR-CL-10Seller identifier scheme: ISO 6523 ICDBR-CL-11Legal registration scheme: ISO 6523 ICDBR-CL-13Item classification scheme: UNTDID 7143BR-CL-14Country code: ISO 3166-1BR-CL-15Item country of origin: ISO 3166-1BR-CL-16Payment means code: UNCL 4461BR-CL-17Allowance/charge VAT category code: UNCL 5305BR-CL-18Invoiced item VAT category code: UNCL 5305BR-CL-19Allowance reason code: UNCL 5189BR-CL-20Charge reason code: UNCL 7161BR-CL-21Item standard identifier scheme: ISO 6523 ICDBR-CL-22VAT exemption reason code: CEF VATEXBR-CL-23Unit of measure code: UN/ECE Rec 20BR-CL-24Attached document MIME code: MIME media typeBR-CL-25Electronic address scheme: CEF EASBR-CL-26Deliver-to location scheme: ISO 6523 ICDPEPPOL-EN16931-CL001Attachment MIME type must come from the allowed listPeppol BIS 3.0PEPPOL-EN16931-CL002Document allowance reason code must come from UNCL 5189Peppol BIS 3.0PEPPOL-EN16931-CL003Charge reason code must come from UNCL 7161Peppol BIS 3.0PEPPOL-EN16931-CL006VAT point date code must come from UNCL 2005Peppol BIS 3.0PEPPOL-EN16931-CL007Currency codes must be valid ISO 4217 codesPeppol BIS 3.0PEPPOL-EN16931-CL008Electronic address scheme must be a registered EAS codePeppol BIS 3.0BR-DE-17Invoice type code should use the allowed UNTDID codesXRechnungBR-DEX-01Attachment MIME code must be allowedXRechnungBR-DEX-04Scheme identifier must come from the ISO 6523 ICD listXRechnungBR-DEX-05Scheme identifier must come from the ISO 6523 ICD listXRechnungBR-DEX-06Scheme identifier must come from the ISO 6523 ICD listXRechnungBR-DEX-07Endpoint scheme identifier must be a CEF EAS codeXRechnungBR-DEX-08Delivery location scheme must be an ISO 6523 ICD codeXRechnungBR-DE-CVD-04BT-158 with scheme CVD must hold a vehicle categoryXRechnungBR-DE-CVD-05The cva attribute value must come from the allowed listXRechnung
Process & profile
PEPPOL-EN16931-P0100Invoice type code must match the Peppol profilePeppol BIS 3.0PEPPOL-EN16931-P0101Credit note type code must match the Peppol profilePeppol BIS 3.0PEPPOL-EN16931-P0112Type codes 326 and 384 are reserved for German tradePeppol BIS 3.0PEPPOL-EN16931-R001The business process must be statedPeppol BIS 3.0PEPPOL-EN16931-R004Specification identifier must be Peppol BIS Billing 3.0Peppol BIS 3.0PEPPOL-EN16931-R007The business process must follow the Peppol URN patternPeppol BIS 3.0
Frequently asked questions
What is an EN 16931 BR-* rule?
A BR-* rule is a business rule of the EN 16931 standard that an electronic invoice must satisfy. BR-* covers content rules, BR-CO-* conditional/calculation rules, BR-DEC-* decimal rules and BR-CL-* code-list rules. A validator flags a rule when the invoice breaks it.
What is the difference between BR, BR-CO, BR-DEC and BR-CL?
BR-* are core content rules (a field must be present). BR-CO-* are conditional and calculation rules (totals must add up). BR-DEC-* constrain decimal places. BR-CL-* check that codes come from the correct code list (currencies, countries, VAT categories, units).
How many EN 16931 rules are there?
ValidateFin documents 176 EN 16931 business rules - the near-complete set enforced on Peppol BIS, UBL, XRechnung and Factur-X invoices, covering content rules (BR-*), calculation rules (BR-CO-*), decimal rules (BR-DEC-*) and code-list rules (BR-CL-*).
What is the difference between an error and a warning?
A fatal rule is an error: the invoice is rejected until it is fixed. A warning flags a likely problem but does not block the invoice. Each rule page shows its severity.
Which formats do these rules apply to?
EN 16931 is syntax-neutral, so the same rules apply to UBL (Peppol BIS Billing 3.0), XRechnung and Factur-X / ZUGFeRD (CII). A rule such as BR-CO-10 must hold whichever syntax you use.
How do I fix an invoice that fails a rule?
Open the rule to read what it checks and the exact correction, then re-validate your file with the matching free validator (UBL/Peppol, XRechnung or Factur-X). Everything runs in your browser - no upload.
Where do these rules come from?
They are the official EN 16931 business rules published by CEN and enforced through the official Schematron. ValidateFin's validators run that official Schematron, and each rule page mirrors its meaning.
Do the rules apply the same way to Factur-X and XRechnung?
Yes - both must satisfy the EN 16931 core rules. XRechnung adds German KoSIT (BR-DE-*) rules on top, and Factur-X applies them in the CII syntax, but the EN 16931 core is identical.