VAT Number Lookup: How to Check if a Company Is VAT Registered

Checking VAT numbers is a crucial step of tax compliance when selling B2B. Before you apply the reverse charge to a sale, you have to confirm your buyer really is a VAT registered business — and the only way to do that is a VAT number lookup against the register of the country that issued it.

This guide covers how to check if a company is VAT registered in each of those three systems, how to find a company VAT number when you only have a name, and what to do when a number fails.

Why You Need to Check VAT Numbers

Unfortunately, there's a problem of VAT fraud, wherein people provide false business IDs so they can avoid paying consumption tax on their purchases. In places that are cracking down on fraud, such as the European Union, it's your responsibility to verify that these business tax IDs are valid.

If you don't check the validity of a customer's VAT identification number, and you apply the reverse charge mechanism to a sale where the buyer has a fake VAT ID, then the consumption tax comes out of your own pocket. The authority does not pursue the buyer who lied to you. It pursues the seller who failed to check.

If you are not yet sure what you are looking at, our guide to what a VAT number is covers the formats, country codes and what each part means.

How a VAT Number Lookup Works

Most countries publish a free lookup tool on their tax agency website. It is a manual process: visit the site, find the verification service, type in your customer's tax ID, search — then repeat for every customer.

Two things to know first. These tools tell you whether a number is valid right now, so a valid vat number from last quarter may since have been deregistered — which is why the check belongs at the point of sale. And some services ask for your own number before they will run the query, so have it handy.

How to Check an EU VAT Number

For the European Union, the lookup runs through the European Commission's official validation service, VIES. Choose the country, enter the number, add your own VAT details, and verify.

VIES covers all 27 member states plus Northern Ireland, and some countries return a consultation reference number you can keep as proof of the check. It has real limitations too — the data comes from national databases that can be wrong or briefly offline, and a valid number tells you nothing about whether the business is trustworthy.

How to use VIES, step by step walks the full process and those limitations in detail.

How to Check a UK VAT Number

Since Brexit, UK numbers are outside VIES and need HMRC instead.

1. Go to HMRC's page to check a UK VAT number.
2. Click "Start now" to access the VAT lookup tool.
3. Enter the UK VAT number of the business in question.
4. Click the box if you want to record legal proof that you've checked the number.
5. Click "Search" and the results will appear on the page.

Do tick that box. HMRC then issues a timestamped certificate confirming you checked, and if the number later proves invalid, that record stands between you and the assessment. The service returns the registered name and address, so you can also confirm the number belongs to the company you are dealing with.

How to Check a VAT Number in South Africa

South Africa's revenue service, SARS, runs the VAT Vendor Search — and unusually, it searches in both directions.

1. Go to South Africa's SARS eFiling system VAT Vendor Search.

2. You must agree to the terms and conditions, then click "Continue to VAT Vendor Search."

3. You'll see the VAT Vendor Search page with several options to choose from. You should select "Verify a VAT registration number (VAT registration number required)"

   

4. Provide the VAT registration number or the VAT trading name of the business in question.

   

5. The VAT lookup should return results.

6. You can print or save your search results. This might be worthwhile to keep in your tax records.

The second option in step 4 is the useful one. Because SARS accepts a VAT trading name as well as a number, it is one of the few official tools where you can find a company VAT number starting from the name — something VIES cannot do at all.

How to Find a Company VAT Number by Name

This is the request that sends most people in circles, because the major tools are built to validate a number, not to discover one. VIES takes a number and returns a name; it will not run backwards.

When you only have a name, work through these in order:

• Their own paperwork. Any VAT invoice they issued must show their number, as must most quotes and contracts.
• Their website. In the EU and UK it is commonly in the footer, terms page or imprint.
• The national business register. Many publish the VAT identification number alongside the company registration number. Those are different identifiers, so check which you are reading.
• SARS, if the supplier is South African, which searches by trading name directly.
• Ask them. For a B2B sale this is normal, and a business is VAT registered or it is not — a legitimate one hands the number over without hesitation. Reluctance is itself information.

Third-party sites promising name-to-number search work from cached scrapes, not live registers. Treat what they return as a lead to verify officially, never as proof.

What to Do If the Number Is Invalid

A failed check is not necessarily fraud:

1. Re-enter it. Strip spaces, dots and the country prefix if the tool adds its own. Formatting causes most false negatives.
2. Check the country. A number run against the wrong member state fails even when valid.
3. Try again shortly. The national databases behind these tools go offline for maintenance.
4. Ask the customer. A business that just had to register for VAT may not be visible yet; a deregistered one fails correctly.
5. If it still fails, charge the VAT. Treat it as B2C. You can refund and reissue later against a valid VAT number; you cannot easily recover tax you never collected.

Check VAT Numbers Automatically

It's not always as straightforward as the examples above, and even then the process is manual — one number, one country at a time, while a customer waits at your checkout.

That's why it's best to use a tax compliance tool that checks tax IDs for you automatically.

Quaderno verifies EU VAT numbers through our integration with the Commission's service, VIES. If the tax ID is invalid, the sale will not go through. That protects you from consumption tax fraud and from paying the VAT tax out of pocket.

Quaderno also applies the reverse charge to valid B2B sales, calculates the right VAT on B2C sales, and sends tax-compliant receipts customized to your brand. When deadlines arrive, you can file VAT returns in minutes using instant tax reports showing exactly how much VAT you collected and paid in each jurisdiction.