UK VAT Registration Numbers in 2026: Format, Where to Find One and How to Check It

A VAT registration number is the 9-digit reference HMRC gives every VAT-registered business. You need yours on every VAT invoice you issue. You need your suppliers' numbers to be valid before you reclaim the VAT they charge you. This guide explains what a UK VAT number looks like in 2026, where to find your own or another company's, and how to check it with HMRC — or with the EU's VIES service for Northern Ireland and EU numbers. It also covers what a VAT invoice must show and what to do if a number doesn't check out.

Quick answer

A UK VAT registration number is 9 digits, usually shown as GB 123 4567 89. You'll find a supplier's number on its invoices, receipts or website. Check it for free on HMRC's Check a UK VAT number service, which confirms it's valid and shows the business name and address it's registered to. Use the EU's VIES service for EU numbers and for Northern Ireland XI numbers.

• Every VAT invoice must show the supplier's VAT number and the VAT as a separate amount

• HMRC's checker can't search by company name — you need the number

• Your own number is in your VAT online account and on HMRC's registration confirmation

• Don't reclaim VAT from an invoice with an invalid number — ask the supplier first

• You must register once taxable turnover goes over £90,000 in 12 months

What a UK VAT registration number is

When a business registers for VAT — because its taxable turnover has gone over the £90,000 threshold, or because it chose to register voluntarily — HMRC issues a VAT registration number. GOV.UK describes it as a 9-digit number that you must include on all the invoices you raise. The number identifies the business on its VAT returns, on Making Tax Digital software, on invoices and in correspondence with HMRC.

A VAT number isn't the same as other HMRC and Companies House references. Your Unique Taxpayer Reference (UTR) is a 10-digit number for Self Assessment or Corporation Tax. Your company registration number comes from Companies House and is usually 8 characters. Your PAYE reference is for payroll. Mixing them up on an invoice or a supplier form is one of the most common reasons a "VAT number" fails a check. See our UTR number guide if you need that one instead.

Only VAT-registered businesses can issue VAT invoices. A business that isn't registered must not charge VAT or show an amount as VAT on its invoices.

UK VAT number format

The GB prefix is a country code. Many businesses print just the 9 digits on UK invoices. When you check a number, start with the 9 digits and, if that fails, try again with the prefix in case the form expects it.

The XI prefix is for Northern Ireland businesses trading goods with the EU under the Windsor Framework. They tell HMRC they're operating under the framework, receive an email confirmation, and then use XI in front of their usual number on all documents for EU customers and suppliers — for example, XI 123456789 instead of GB 123456789. HMRC's guidance says the XI prefix isn't used for services, for transactions within the UK or for trade with the rest of the world. Those keep the GB format.

Where to find your own VAT number

If you're the VAT-registered business, you'll find your number in several places:

• HMRC's registration confirmation. After you register, HMRC sends your VAT number, your effective date of registration and details of your first return by post.
• Your VAT online account. Sign in to your HMRC business tax account and open the VAT section. GOV.UK tells you to sign up for the VAT online account as soon as you receive your number.
• Previous VAT returns and HMRC letters. Your number appears on every return and on VAT correspondence.
• Your accounting or Making Tax Digital software, and your accountant if they file for you.

If you've applied but haven't heard back, you won't have a number yet, and HMRC's checker won't show you. You can't charge VAT on invoices while you wait. GOV.UK suggests increasing your prices to cover the VAT you'll owe from your effective date of registration, then reissuing the invoices with VAT shown once your number arrives. Our VAT registration guide covers the application itself.

How to find a company's VAT registration number

There's no public directory of VAT numbers that you can search by business name. HMRC's checking service works only when you already have the number, and Companies House doesn't record VAT registrations. To find a supplier's or customer's VAT number:

• Look at their VAT invoice. By law a full VAT invoice must show the supplier's name, address and VAT registration number, so this is the most reliable place.
• Check receipts and order confirmations. Shops' till receipts and simplified invoices also show the VAT number.
• Look at their website. Many businesses show it in the footer, on the contact page or in their terms and conditions.
• Ask them. For a new supplier, ask for the VAT number on your supplier set-up form, together with the legal name it's registered under.

If a business that should be VAT-registered won't give you a number, or gives you one that doesn't match its name, treat that as a warning sign.

How to check a UK VAT number with HMRC

Check a UK VAT number

1. 1

   Get the number

   Copy it exactly from the invoice or supplier form, digit by digit.

2. 2

   Open HMRC's checker

   Go to 'Check a UK VAT number' on GOV.UK and select Start now. There's no fee and no sign-in.

   Check a UK VAT number
3. 3

   Enter the number

   HMRC tells you whether the number is valid and shows the name and address of the business it's registered to.

4. 4

   Get proof of the check (optional)

   If you're VAT-registered, enter your own VAT number as well. You'll get a record showing when you checked, which is useful evidence for your files.

5. 5

   Compare the details

   Make sure the registered name and address match the business that invoiced you. A valid number registered to a different business is a red flag.

A valid result confirms the number exists and who it belongs to. It doesn't prove the invoice is genuine, or that the supplier has charged the right rate. For large or unusual purchases, check the number when you first set up the supplier, and again periodically — businesses deregister, merge or change their legal entity.

The service also has a Welsh-language version. Businesses that need to check large numbers of VAT numbers automatically often use accounting software that connects to HMRC's checking service.

Checking XI and EU VAT numbers on VIES

For VAT numbers issued by EU member states, use the European Commission's VIES (VAT Information Exchange System) service. HMRC's own checker links to it. Northern Ireland businesses trading goods with the EU use XI numbers, and these are checked on VIES too.

This matters most if you're in Northern Ireland and sell goods to EU businesses. GOV.UK says you can zero-rate goods supplied from Northern Ireland to a VAT-registered EU business, and that you can check whether its VAT number is valid. Keep a record of the VIES check alongside your evidence that the goods left Northern Ireland.

Standard GB numbers are no longer on VIES, because Great Britain left the EU VAT system at the end of 2020. If a VIES check on a GB number fails, that doesn't mean the number is invalid — check it with HMRC instead.

What a VAT invoice must show

A valid VAT invoice is the main evidence you need to reclaim VAT as input tax. HMRC's VAT Notice 700/21 lists what a full VAT invoice must include:

• a unique, sequential invoice number
• the time of supply (tax point), and the date of issue if different
• the supplier's name, address and VAT registration number
• the customer's name and address
• a description that identifies the goods or services
• for each item: the quantity, the unit price, the VAT rate and the amount excluding VAT
• the total amount excluding VAT
• any cash discount offered
• the total VAT, shown in sterling

You normally have to issue a VAT invoice within 30 days of the supply. If a supply is £250 or less including VAT, you can issue a simplified invoice. This shows your name, address and VAT number, the time of supply, a description, the VAT rate and the total including VAT. Above £250, a customer who asks for an invoice must get a full or modified VAT invoice. Special rules apply to reverse charge and margin scheme invoices. Construction invoices under the domestic reverse charge, for example, must say the reverse charge applies.

Example: a printing firm invoices you £1,000 plus VAT at 20% — £1,200 in total. If the invoice shows a valid VAT number and meets the rules, you can reclaim £200 on your VAT return. If the number is invalid, or missing altogether, you have no evidence for that £200. If HMRC finds it during a compliance check, you'll have to pay it back.

Create compliant invoices with our free invoice generator, and work out VAT-inclusive and VAT-exclusive prices with the VAT calculator.

Work out the VAT on an invoice

Add TaxRemove Tax

AmountTax Rate

20% (Standard)5% (Reduced)0% (Zero-rated)

Net Amount (Before Tax)£1,000.00

Tax (20%)£200.00

Gross Amount (Including Tax)£1,200.00

Open the full VAT Calculator (PDF, save, compare)

What to do if a VAT number is invalid

A failed check isn't always fraud. Work through the likely causes before you act.

1. Re-check the number. A transposed digit, an extra digit from a branch suffix or the wrong prefix is the most common cause. Try it with and without the GB prefix.
2. Make sure it's really a VAT number. Suppliers sometimes quote their company number or UTR by mistake.
3. Ask the supplier. Ask them to confirm the number and the exact legal name it's registered under. A newly registered business may be waiting for its number — in that case it shouldn't be showing VAT on invoices yet.
4. Consider deregistration or a change of entity. A business that has deregistered, or moved from sole trader to limited company, may still be using an old number.
5. Hold the VAT. Until you have a valid VAT invoice, don't reclaim the VAT on your return. Many businesses pay the net amount and hold back the VAT until the supplier sends a corrected invoice.
6. Ask for a corrected invoice. If the supplier isn't VAT-registered, it isn't entitled to charge VAT. Ask for an invoice for the net amount only.

HMRC's input tax guidance (VIT12200) says that where an invoice wrongly shows a sum as VAT — for example from someone who isn't registered — you can't treat it as input tax. An extra-statutory concession (ESC 3.9) covers some of these cases. Speak to HMRC or your accountant if you've already paid and can't recover the money from the supplier.

When a VAT number changes hands

A VAT number belongs to the legal "person" that registered, not to a shop or a brand. A sole trader is registered as an individual, and a limited company has its own registration, separate from its directors. So if a sole trader incorporates, the new company normally needs its own VAT registration — unless it applies to take over the old number.

GOV.UK lets you transfer a VAT registration number when a business changes ownership or legal status — for example, when you buy a company and want to keep its number, or a partnership becomes a sole trader. Both sides complete form VAT68, and the new owner registers for VAT. If the seller passes on the number, they must also give the VAT records to the buyer. Buyers who would rather start clean can get a new number instead: the old registration is cancelled and the buyer registers again.

When a business changes hands

Step 1

Sale or change of legal status

Step 2

Keep the number

form VAT68 + new registration

Step 3

Or get a new number

old registration cancelled

Step 4

Customers re-check the number

For customers, this is why a long-standing supplier's number can suddenly fail a check, or show a slightly different name. Ask the supplier which entity now invoices you, update your records, and re-check the new number.

VAT number fraud: warning signs

The most common VAT number fraud is simple. Someone who isn't registered adds 20% "VAT" to the bill, prints a made-up or borrowed number on the invoice and keeps the money. The customer believes they can reclaim it, and finds out they can't only when HMRC checks their return. Larger frauds involve businesses that register, collect VAT and disappear without paying it to HMRC.

Watch for:

• a number that fails HMRC's check, or is registered to a different name or address
• a supplier who refuses to give a VAT number but still charges VAT
• invoices that show VAT but no VAT number, or don't show the VAT as a separate amount
• a supplier's bank account in a different name from the business
• prices well below the market rate, especially for goods traded in long supply chains (phones, metals, fuel or labour)
• unexpected emails or texts claiming to be from HMRC about VAT refunds — check them against GOV.UK's guidance on recognising genuine HMRC contact before you click anything

You can report suspected VAT fraud to HMRC online, or call the HMRC fraud hotline on 0800 788 887. You don't have to give your name. For genuine questions about your own VAT registration, use the VAT helpline on 0300 200 3700. Our HMRC contact numbers guide lists the others.

Common mistakes with VAT numbers

• Putting the UTR or company number in the VAT field. Each reference has a different format, so check it's 9 digits.
• Charging VAT before you have a number. You can't show VAT on invoices until HMRC issues your number. Raise your prices instead and reissue the invoices later.
• Using XI for everything in Northern Ireland. XI is only for trade in goods with the EU. Use GB for UK and services transactions.
• Not re-checking suppliers. A number that was valid when you set up the supplier may not be today.
• Reclaiming VAT from a simplified invoice over £250. Ask for a full VAT invoice.
• Assuming a VIES failure means a GB number is invalid. GB numbers aren't on VIES — check them with HMRC.

Official links

• Check a UK VAT numberHMRC's free checker
• VIES VAT number validationEU and XI numbers
• Register for VATGetting your VAT number and the XI prefix
• Record keeping for VAT (Notice 700/21)What a VAT invoice must show
• Charge, reclaim and record VATCharging and reclaiming VAT
• Report tax fraud to HMRCOnline form or fraud hotline

What to do next

If you're registered, save your VAT number somewhere you and your bookkeeper can find it, and make sure it's on every invoice template. If you're about to pay a new supplier, check its number on HMRC's service, save the result, and compare the registered name with the invoice. Close to the £90,000 threshold? Read our VAT registration guide and our Making Tax Digital guide so you're ready to file from day one.

This is general information, not legal or tax advice — confirm on the official source or with a professional.

Frequently asked questions

What does a UK VAT registration number look like?

A standard UK VAT number is 9 digits, usually written with the country prefix GB — for example GB 123 4567 89. Some branch registrations add a 3-digit suffix, making 12 digits. Government departments and health authorities use short GD and HA formats. Businesses trading goods between Northern Ireland and the EU use the prefix XI instead of GB on those transactions.

How can I find a company's VAT registration number?

Look on its invoices, receipts, order confirmations or the footer of its website — VAT-registered businesses must show the number on every VAT invoice. If you can't find it, ask the company. HMRC's checker can't search by business name, and Companies House doesn't hold VAT numbers, so there's no public directory you can search by name.

How do I check if a UK VAT number is valid?

Use HMRC's free 'Check a UK VAT number' service on GOV.UK. Enter the number, and it confirms whether it's valid and shows the name and address of the business it belongs to. If you're VAT-registered, enter your own VAT number too, and you'll get a reference that proves when you made the check.

Where can I find my own VAT number?

It's on the registration confirmation HMRC sends when you register, and in your VAT online account within your HMRC business tax account. It also appears on your previous VAT returns and on correspondence from HMRC about VAT. If you use an accountant, they'll have it too. You can't use the public checker to look up your own number by name.

What should I do if a supplier's VAT number is invalid?

Check for typing errors first, then ask the supplier to confirm the number and the exact name it's registered under. Don't reclaim the VAT on that invoice until you have a valid VAT invoice. If the supplier isn't registered, it shouldn't be charging VAT at all, so ask for a corrected invoice. If you suspect fraud, report it to HMRC.

Can I check an XI or EU VAT number?

Yes. Use the European Commission's VIES service for VAT numbers issued by EU member states and for Northern Ireland XI numbers used in trade in goods with the EU. Since the UK left the EU VAT system at the end of 2020, standard GB numbers are checked with HMRC's own service rather than VIES.

Sources & verification

Figures on this page were checked against the sources below when it was last reviewed on 7 October 2026. Each rate and limit is stored once with its own official source and review date, and official update channels are monitored daily so changes are picked up. How we verify

1. 1.Check a UK VAT number — GOV.UK (HMRC) · accessed 7 October 2026
2. 2.Register for VAT — GOV.UK (HMRC) · accessed 7 October 2026
3. 3.Record keeping for VAT (VAT Notice 700/21) — HM Revenue & Customs · accessed 7 October 2026
4. 4.Charge, reclaim and record VAT — GOV.UK (HMRC) · accessed 7 October 2026
5. 5.VAT input tax manual — VIT12200 — HMRC internal manual · accessed 7 October 2026
6. 6.VATNIEU2100 — XI prefix — HMRC internal manual · accessed 7 October 2026
7. 7.Report tax fraud or avoidance to HMRC — GOV.UK (HMRC) · accessed 7 October 2026
8. 8.VIES on-the-Web — European Commission · accessed 7 October 2026
9. 9.How to check a UK VAT number — ANNA Money · accessed 7 October 2026