How to Check if a Business is VAT Registered
- Comfort Iyiewuare
- 10 hours ago
- 4 min read
Knowing how to check if a business is VAT registered is one of those things that seems minor until it isn't. If you claim back VAT on an invoice where the supplier isn't genuinely registered, HMRC will disallow it. That means money out of your pocket, and potentially an enquiry into your supplier too.
Whether you have their VAT registration number or not, here's exactly what to do.
Why check if a business is VAT registered?
There are several situations where verifying a supplier's VAT registration number is the right call:
You're onboarding a new supplier and want to carry out basic due diligence
You've received an invoice showing VAT but something doesn't feel right
You're preparing a VAT return and want to make sure your input tax claims are watertight
Important: It's an offence for a business to charge VAT if they're not VAT registered. If you've paid VAT to an unregistered supplier, HMRC won't recognise it as VAT — meaning you can't reclaim it. Penalties for incorrectly charging VAT can reach 100% of the VAT amount involved.
How to check a UK VAT registration number
If you already have your supplier's VAT number, verifying it takes about 30 seconds. Head to HMRC's official VAT number checker at gov.uk/check-uk-vat-number, enter the number, and you'll see the registered business name and address. If those details match who you're dealing with, you're good to go.
Tip: enter your own VAT registration number at the same time and the system will generate a reference number for the check. Handy to keep on file in case HMRC ever queries it.
How to check if a business is VAT registered without a VAT number
This is where it gets a little trickier. There's no official HMRC tool for searching by company name, so your first step should be to simply ask your supplier. Any VAT-registered business is required to provide a valid VAT invoice, one that clearly shows their VAT registration number.
If you'd rather do some groundwork first, there are third-party websites that let you search by company name and will return a VAT number where one exists. Search 'VAT number search' in your browser and several options will appear. A few things to be aware of with these sites:
They're not official government sources, so data can be incomplete or out of date
Some show de-registered VAT numbers that are no longer valid
Businesses that are part of a VAT group may not appear individually
Isle of Man registrations may or may not be included, depending on the site
Once you have a number, always cross-check it on the official HMRC tool to confirm it's current and belongs to the right business.
One thing worth knowing: it's not unheard of for a new VAT registration number to appear on third-party sites before the business has even received their HMRC confirmation letter. That's a postal processing delay on HMRC's end and nothing to be concerned about.
How to verify an EU VAT number
If you're dealing with a European supplier, the EU runs a dedicated VAT checking tool called VIES (VAT Information Exchange System), available at ec.europa.eu/taxation_customs/vies.
To use VIES, you'll need both your own VAT number and your supplier's. Enter the supplier's country in the first field, then their VAT number without the country prefix. Add your own country and VAT number in the remaining fields. Countries are listed alphabetically by their VAT code; Spain appears under ES, France under FR and so on.
One caveat is some EU countries operate a two-tier VAT number system, and not all registrations are automatically included in VIES. If a number doesn't appear, it may mean the business isn't registered for cross-border EU trading, rather than being unregistered altogether.
VAT registration: common questions
What is a VAT registration number?
A VAT registration number is a unique nine-digit identifier issued by HMRC to every VAT-registered business in the UK. It's typically shown on invoices with a GB prefix (e.g. GB123456789).
When does a business have to register for VAT?
UK businesses must register for VAT once their taxable turnover exceeds £90,000 in any rolling 12-month period. Businesses based outside the UK must register as soon as they make any taxable supply here, regardless of turnover. Some businesses below the threshold choose to register voluntarily, particularly if they sell mainly to other VAT-registered businesses and want to reclaim VAT on their own costs.
Can I reclaim VAT if the invoice shows the wrong VAT number?
No. An invoice with an incorrect or invalid VAT registration number isn't a valid VAT tax invoice, so HMRC will disallow any input tax claim. Contact your supplier and ask them to reissue a corrected invoice before you submit your return.
Should I check VAT numbers as part of supplier due diligence?
Yes, it should be a standard step whenever you take on a new supplier. Verifying their VAT registration number up front means no surprises when your VAT return is reviewed. You can run the check at gov.uk/check-uk-vat-number.
How to check VAT registration: quick reference
Location | I have their VAT number | I don't have their VAT number |
UK | Ask your supplier for a VAT invoice or search online for their VAT number then verify on HMRC | |
EU | Ask your supplier or use VIES name search where available |
Need specialist VAT advice? Whether it's supplier due diligence, VAT return preparation, or a HMRC query, our team is here to help. Get in touch with us today.