§ VAT FORMAT — GB
United Kingdom VAT number format
Prefix GB · 9-digit standard, 12-digit branch, or GD/HA prefix for government and health
§ PATTERN
9-digit standard, 12-digit branch, or GD/HA prefix for government and health
^GB(\d{9}|\d{12}|GD\d{3}|HA\d{3})$§ EXAMPLES
- GB123456789
- GB123456789001
- GBGD123
- GBHA999
Synthetic examples — do not represent real registered businesses.
§ NOTES
- 01
The 9-digit format is the standard issued to most VAT-registered businesses.
- 02
12-digit numbers are issued to branches of corporate groups.
- 03
GD prefix denotes government departments; HA denotes NHS health authorities.
- 04
Spaces and hyphens are stripped before validation.
§ VALIDATION SOURCE
HMRC
UK numbers are validated live against HMRC. Countersure is wired directly to the HMRC Check VAT Number API.