Check VAT in UBL invoices
Extracts VAT categories, percentages and amounts from cac:TaxTotal and compares declared VAT with calculated VAT.
Paste or load UBL XML
Common VAT errors in UBL
- Wrong VAT percentage on a line (e.g. 19% instead of 21%).
- VAT amount per category does not match TaxableAmount × Percent / 100.
- Missing TaxCategory ID (e.g. S, AE, K, Z, E, O, G).
- Mixed VAT rates without separate TaxSubtotal blocks.
- Reverse charge (AE) used without the required text/note.
- Exempt VAT (E) used without an exemption reason.
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Frequently asked questions
›Why does the calculated VAT differ from the declared VAT?
Most often this is rounding. UBL allows VAT to be rounded per category, and small differences (≤ 0.02) are usually acceptable.
›What does category AE mean?
AE is the reverse-charge category code. With AE the supplier does not charge VAT; the buyer accounts for it. Other zero-VAT codes include K (intra-community), Z (zero rated), E (exempt), G (export), O (outside scope).