UK VAT Generator
Valid UK corporate Value Added Tax (VAT) number generator for fiscal QA testing.
Waiting for generation...
About UK Value Added Tax (VAT)
The Value Added Tax (VAT) is a unique 9-digit tax identification number assigned to business entities operating in the United Kingdom for tax reporting purposes.
Our tool generates mock 9-digit VAT numbers. We support generation using both the classic weighted Modulo 97 algorithm and the new alternative algorithm (+55) introduced for newer commercial business blocks.
Anatomy & Structure of UK VAT (9 Digits)
The UK VAT registration number issued by HMRC features 3 structural components:
| Position | Field | Length | Meaning & Rule | Example |
|---|---|---|---|---|
| Prefix | Country Code | 2 letters | Optional ISO "GB" prefix for cross-border trade | GB |
| 1 to 7 | Base Number | 7 digits | Sequential business registration number with HMRC | 1234567 |
| 8 & 9 | Check Digits | 2 digits | Two-digit checksum computed via Modulo 97 (standard or +55) | 89 |
UK VAT Validation Algorithm (Standard & Alternative Modulo 97)
HMRC verifies the final 2 digits using positional weights from 8 down to 2:
(Sum + CheckDigits) % 97 == 0 || (Sum + 55 + CheckDigits) % 97 == 0
- 1. Extract the first 7 base digits.
- 2. Multiply each digit by position weights: [8, 7, 6, 5, 4, 3, 2] and calculate total Sum.
- 3. Standard Check: verify if (Sum + CheckDigits) % 97 == 0.
- 4. Alternative Check (+55): verify if (Sum + 55 + CheckDigits) % 97 == 0.
- 5. The VAT number is valid if either standard or alternative rule succeeds.