BR-CO-15
EN 16931
FATAL
The invoice total with VAT (BT-112) must equal the total without VAT (BT-109) plus the total VAT amount (BT-110). This is the single most-hit calculation rule - almost always a 1-cent rounding drift between the VAT breakdown and the declared totals.
How to fix it
- Recompute BT-112 = BT-109 + BT-110 after both sides are rounded to 2 decimals.
- Compute BT-110 as the sum of the per-category VAT amounts (BT-117) - not as rate × grand total, which drifts by a cent on mixed-rate invoices.
- Use one rounding helper everywhere; mixing
round()implementations across languages is a classic cause.
− Rejected
<TaxExclusiveAmount>875.00</> <TaxAmount>218.75</> <TaxInclusiveAmount>1093.74</>
+ Accepted
<TaxExclusiveAmount>875.00</> <TaxAmount>218.75</> <TaxInclusiveAmount>1093.75</>
Official rule text
Invoice total amount with VAT (BT-112) = Invoice total amount without VAT (BT-109) + Invoice total VAT amount (BT-110).
Developers also reach this page searching for an “invoice validation error”, an “e-invoice rejected” message, or how to fix a failed EN 16931 compliance check — it's the same issue, explained above.
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