How to check a VAT number

In this guide we explain how to find and check VAT registration numbers so you can reclaim VAT paid to suppliers.

VAT return submission on open laptop

What is a VAT number?

A VAT number is a unique identification number given to VAT-registered businesses. In England, Scotland and Wales, a VAT number is a nine-digit code with the prefix ‘GB’. VAT numbers are issued by HMRC. In Northern Ireland, VAT registered businesses use the prefix XI to trade under the Northern Ireland Protocol.

You’ll only have a VAT number if you’ve registered your business to pay VAT. Once registered, you need to add VAT to your sales invoices, and also reclaim any VAT you’ve paid to your suppliers. You’ll need your supplier’s VAT number to do this.

Can a business trade without a VAT number?

If a business has a VAT taxable turnover above the threshold of £85,000 a year, they must register to pay VAT. If their turnover is below this, registering for VAT is voluntary.

If you trade with a business that is not VAT registered, you must still add VAT to your invoices, collect the VAT, and pay it to HMRC. Your customer will not be able to reclaim the VAT from HMRC.

If you buy something from a business that is not VAT registered, they cannot add VAT to their invoice to you, so you can’t reclaim it.

How to find a business’ VAT number

The first place to look for a business’ VAT number is on their invoice to you. If a business is registered for VAT, their unique VAT registration number should be on all their invoices.

If a business has charged you VAT, but there’s no VAT number on their invoice, you need to contact them. You need a valid invoice to reclaim the VAT you’ve paid.

Checking a VAT number is valid

Sometimes you might want to check that a VAT number is valid, such as when you’re dealing with a new supplier. If you use an invalid VAT number when reclaiming VAT expenses, HMRC will reject your claims.

Be sure to check that the number is nine digits long, as this is the valid format for a VAT registration number.

There are a couple of ways to check a UK VAT registration number. HMRC have a VAT number checker, or you can call their VAT helpline on 0300 200 3700. You’ll need your own VAT number to use this service.

Do all countries have VAT numbers?

Over 170 countries use the VAT system, including all European countries. Each country has its own format for VAT numbers. In the EU, VAT numbers are prefixed with a two-letter country code. HMRC has a list of the different country codes and formats.

To check if an EU or Northern Ireland VAT number is valid, use the VIES VAT Validation Service.

The United States doesn’t use the VAT system. Instead, they have something called sales-tax (which can vary between states), which you can’t claim back.

Is a VAT number the same as a UTR number?

A Unique Taxpayer Reference (UTR) number is a 10 digit code issued by HMRC to self-assessment taxpayers. It’s separate from a VAT registration number.

Handling VAT for small businesses

To find out more about claiming back VAT, check out Xero’s free VAT Guide. You’ll find lots of practical advice on how to handle core VAT-related tasks, including filing VAT returns in line with Making Tax Digital.


Xero does not provide accounting, tax, business or legal advice. This guide has been provided for information purposes only. You should consult your own professional advisors for advice directly relating to your business or before taking action in relation to any of the content provided.

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