VAT number format UK: nine digits, with or without GB
The VAT number format UK businesses use is nine digits, often written with GB in front, for example GB123456782.
Spaces are optional, so GB 123 4567 82, GB123456782 and 123456782 all describe the same number. Your VAT registration certificate shows yours.
The format in one table
| What you see | What it is |
|---|---|
| 123456782 | The nine digits on their own |
| GB123456782 | The nine digits with GB at the start |
| GB 123 4567 82 | A number written with GB and spaces, one of the forms Kofolio copies |
All UK VAT registration numbers have nine digits. GB at the start is optional.
When a form rejects your number
HMRC's guidance for service builders is to accept the number with or without spaces and with or without the GB prefix, then strip both before checking it.
Not every form follows that guidance, so if one rejects your number, try the other written forms in the table above.
Where to find your VAT number
It is on your VAT registration certificate.
For someone else's number, look on their invoices, receipts or website.
How to check a VAT number is valid
A format check only tests the shape. For UK numbers, the last two digits are calculated by a standard formula from the other seven, which is how format checkers test them.
A format check can only confirm that a number fits the required format. It cannot tell you that the number is a current valid registration.
For that, the most reliable method is the official GOV.UK UK VAT number checker. It confirms whether a registration number is valid and shows the name and address of the business it is registered to.
You need the number before you start, because you cannot use the official checker to search by business name.
Kofolio has a free VAT number checker that tests the format and the check digits and shows the forms Kofolio copies. For a live registration, use the GOV.UK checker, which is the better tool for that job.
How Kofolio keeps your VAT number
A Kofolio company card has a VAT number field next to the company number, UTR and PAYE reference.
Click the value to copy it. The VAT number copies in four forms: with GB and spaces, as "GB123456782", the number with spaces, or digits only, so you can paste whichever form a supplier, bank or form asks for.
Press V to copy the VAT number.
The card also counts your VAT return dates down, from the VAT periods you set. See the deadlines page.
Kofolio stores and copies the number. It files nothing for you.
Frequently asked questions
What does a UK VAT number look like?
Nine digits, sometimes with GB at the start. For example, 123456782 or GB123456782.
Do I need the GB at the start?
HMRC's guidance says a UK VAT number is 9 numbers, sometimes with GB at the start, and that spaces can be left out or kept. A form that asks for the number may accept it either way.
How long is a UK VAT number?
Nine digits, not counting GB.
Can I find a VAT number from a company name?
Not with the official checker. GOV.UK says you cannot use it to check whether a business is registered for VAT by searching its name.
Does a correct format mean the VAT number is registered?
No. A format check cannot tell you whether the number is a current valid registration. Use the official GOV.UK checker for that.
Is my VAT number the same as my EORI number?
No. An EORI number is a separate customs number. For a GB EORI you apply for a number that starts with GB, and you need your VAT number to apply if you are VAT registered.
Where is my VAT number?
On your VAT registration certificate.
Keep it ready to copy
Add your company to Kofolio and copy your VAT number in whichever form the next form needs. Kofolio is free. Find your company