The short answer
BR-CO-12 fails when cac:LegalMonetaryTotal/cbc:ChargeTotalAmount disagrees with the document-level charges. Sum cbc:Amount over the cac:AllowanceCharge elements that sit directly under the document root with cbc:ChargeIndicator of true, round to two decimals, and send that as the charge total.
Charges attached to a line stay out of this figure; they are part of the line net amount.
What the rule checks
Only cac:AllowanceCharge children of the Invoice or CreditNote root with cbc:ChargeIndicator of true are summed. Document-level allowances, and any cac:AllowanceCharge inside a line or a price, are left out.
The summed charges are rounded to two decimals and must equal the total exactly. A total of 3.51 against a single charge of 3.50 fails.
Leaving cbc:ChargeTotalAmount out is accepted only when the document has no document-level charges. A charge without a total fails. Without any charges, a total of 0.00 passes and any other value fails.
| Term | Meaning | UBL element |
|---|---|---|
| BT-108 | Sum of charges on document level | cac:LegalMonetaryTotal/cbc:ChargeTotalAmount |
| BT-99 | Document level charge amount | cac:AllowanceCharge[cbc:ChargeIndicator = true]/cbc:Amount |
How an integration ends up here
Possible causes, from the shape of the rule rather than from measured usage:
- Freight, handling or similar fees are stored as a header figure in the source system, and the
cac:AllowanceChargeelements are generated from a different place that does not agree with it. - A line-level charge is counted in the document charge total as well as in its line net amount.
- The
cbc:ChargeIndicatoris wrong on one element, so a charge is summed with the allowances or an allowance with the charges. - The charge elements are written but the total is skipped because the mapping treats it as optional.
- A percentage charge is recalculated for the total instead of reusing the rounded
cbc:Amountthat was written.
How to fix it
- Collect the
cac:AllowanceChargeelements directly under the document root whosecbc:ChargeIndicatoristrue. - Add their
cbc:Amountvalues, as written in the XML, with decimal arithmetic and round to two decimals. - Write the result to
cac:LegalMonetaryTotal/cbc:ChargeTotalAmount. With no document-level charges, omit the element or send 0.00. - Rebuild the total without VAT from the corrected charge total, since
BR-CO-13reads it.
The recorded example has one document-level charge, 10 percent of a 35.00 base.
Document-level charges: 3.50 Charge total sent (BT-108): 4.50, so BR-CO-12 fails Total without VAT sent: 68.50, which is 66.00 - 1.00 + 3.50 Against the 4.50 that was sent, BR-CO-13 expects 66.00 - 1.00 + 4.50 = 69.50, so it fails too
Validate your corrected invoice
Before and after
These are fragments, not complete documents. The complete synthetic documents they come from are linked below.
Fragment of the failing invoice: the total says 4.50, the only document-level charge is 3.50
<cac:AllowanceCharge>
<cbc:ChargeIndicator>true</cbc:ChargeIndicator>
<cbc:AllowanceChargeReasonCode>CG</cbc:AllowanceChargeReasonCode>
<cbc:AllowanceChargeReason>Example document charge</cbc:AllowanceChargeReason>
<cbc:MultiplierFactorNumeric>10</cbc:MultiplierFactorNumeric>
<cbc:Amount currencyID="GBP">3.50</cbc:Amount>
<cbc:BaseAmount currencyID="GBP">35.00</cbc:BaseAmount>
<!-- tax category omitted from this fragment -->
</cac:AllowanceCharge>
<cac:LegalMonetaryTotal>
<cbc:LineExtensionAmount currencyID="GBP">66.00</cbc:LineExtensionAmount>
<cbc:TaxExclusiveAmount currencyID="GBP">68.50</cbc:TaxExclusiveAmount>
<!-- total with VAT omitted from this fragment -->
<cbc:AllowanceTotalAmount currencyID="GBP">1.00</cbc:AllowanceTotalAmount>
<cbc:ChargeTotalAmount currencyID="GBP">4.50</cbc:ChargeTotalAmount>
<!-- prepaid, rounding and payable amounts omitted from this fragment -->
</cac:LegalMonetaryTotal>Fragment of the corrected invoice: the total equals the one charge
<cac:LegalMonetaryTotal>
<cbc:LineExtensionAmount currencyID="GBP">66.00</cbc:LineExtensionAmount>
<cbc:TaxExclusiveAmount currencyID="GBP">68.50</cbc:TaxExclusiveAmount>
<!-- total with VAT omitted from this fragment -->
<cbc:AllowanceTotalAmount currencyID="GBP">1.00</cbc:AllowanceTotalAmount>
<cbc:ChargeTotalAmount currencyID="GBP">3.50</cbc:ChargeTotalAmount>
<!-- prepaid, rounding and payable amounts omitted from this fragment -->
</cac:LegalMonetaryTotal>Only cbc:ChargeTotalAmount differs: 4.50 in the failing document, 3.50 in the corrected one. The failing document also reports BR-CO-13, because its total without VAT of 68.50 was worked out with a charge total of 3.50 and does not fit the 4.50 that was sent. Putting the charge total right clears both findings.
What the validator reported
- The failing invoice reports BR-CO-12 and BR-CO-13. The corrected document passes every layer with no findings.Download the failing XMLDownload the corrected XML
Recorded on phive 12.1.0 / phive-rules-peppol 4.5.6 / Saxon-HE 12.10, the engine behind the free validator, using synthetic data. A recorded result is regression evidence for these documents; it is not a certification.
Where it applies
- Applies to UBL
InvoiceandCreditNotein the same way; a credit note with the same mistake reports the same two findings. - Leaving the total out while a charge is present also reports
BR-CO-13, which then treats the missing charge total as nothing added. - This rule only sums. The reason, VAT category, base amount and percentage of each charge are checked elsewhere.
Related rules
- BR-CO-11 is the matching check for document-level allowances
- BR-CO-13 adds the charge total when it checks the total without VAT
- PEPPOL-EN16931-R040 checks a charge amount against its base amount and percentage
- PEPPOL-EN16931-R041 requires a base amount whenever a charge carries a percentage
- Browse every rule in the reference
Scope and source
Written for Peppol BIS Billing 3.0.21 (May 2026), EN 16931 1.3.16, as applied to UBL 2.1 Invoice and CreditNote documents. Other profiles, syntaxes and releases can define this identifier differently. Guidance version 2026-09-20.1: source checked 2026-09-20, explanation last updated 2026-09-20.
The official definition of BR-CO-12 carries the normative wording and test. This page is our explanation of it, not a copy.
Guidance does not change the engine verdict. Fixing this finding does not mean the document passes every layer, and validation does not certify legal or tax compliance or transmit a document over Peppol.
