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VAT Registration: Who Must Register, When and How to Apply

By VAT Calculatorz · Last updated 6 October 2026

Definition: VAT registration means registering your business with HMRC for VAT, so that you charge VAT on your sales, can reclaim VAT on your business purchases, and get your own 9-digit VAT registration number.

Quick answer: You must register for VAT if your taxable turnover goes over £90,000 in any rolling 12-month period — or if you expect it to go over £90,000 in the next 30 days alone. Below the threshold, registering is your choice (voluntary registration). Check where you stand with the free checker below — and once you are registered, work out the VAT on any price with our VAT calculator.

Try it: Do I Need to Register for VAT?

Enter your taxable turnover for the last 12 months and find out instantly.

Remember: you must also register if you expect your taxable turnover to go over £90,000 in the next 30 days alone — for example, if you have just signed one large contract.

Once you are registered, work out VAT on any price with the full UK VAT Calculator — it's free.

Who Must Register

There are two tests. If either applies, registration is compulsory.

Test 1: The rolling 12-month test

At the end of every month, add up your taxable turnover for the last 12 months. If it goes over £90,000, you must register within 30 days of the end of that month. Your effective date of registration is the first day of the second month after you went over the threshold.

Example: on 15 July your taxable turnover for the last 12 months reaches £100,000 — the first time it has gone over. You must register by 30 August, and your effective date of registration is 1 September.

Test 2: The next-30-days test

You must also register if you realise your taxable turnover will go over £90,000 in the next 30 days alone — register by the end of that 30-day period. Your effective date of registration is the date you realised, not the date the money arrives.

Example: on 1 May you agree a £100,000 contract, to be paid at the end of May. You must apply by 30 May, and your effective date of registration is 1 May.

Other cases where you must register

Two safety valves: if your turnover only goes over the threshold temporarily, you can ask HMRC for a registration "exception"; and if most of what you sell is zero-rated, you can ask HMRC for an exemption from registration (see the FAQs below). If HMRC says no to either request, they will register you. You do not have to register if you only sell VAT-exempt or "out of scope" goods and services.

What Counts as Taxable Turnover

The £90,000 test uses your taxable turnover — the total value of everything you sell that is not VAT-exempt or out of scope. It is a rolling 12 months, not your tax year or accounting year.

It includes:

It does not include: VAT-exempt sales (such as most insurance, health services and education) or sales that are outside the scope of UK VAT.

That is the figure for the checker above. If it is creeping up, re-check monthly — missing the moment you cross £90,000 leads to late-registration bills.

Voluntary Registration: Pros and Cons

Below £90,000 you can register voluntarily. Weigh it up first:

Pros

Cons

Run your numbers in our free VAT calculator to see what charging VAT would do to a typical invoice.

How to Register — Step by Step

  1. Get your details ready. A limited company needs its company registration number, business bank account details and Unique Taxpayer Reference (UTR), plus annual turnover and an estimate of taxable turnover for the next 12 months. Sole traders and partnerships instead need a National Insurance number, ID such as a passport or driving licence, and bank details.
  2. Register online. Most businesses register on GOV.UK using a VAT online account — sign in with your Government Gateway details, or create them when you first sign in. You can save your answers and finish later.
  3. Or use an agent. An accountant or agent can register you and deal with HMRC on your behalf; you can still open your own VAT online account once you have your number.
  4. Paper form VAT1 — only in specific cases. You must register by post on form VAT1 if, for example, you are applying for a registration exception, joining the Agricultural Flat Rate Scheme, registering divisions of a company separately, or you are a local authority or an insolvency practitioner.
  5. Receive your VAT registration certificate. HMRC sends your 9-digit VAT registration number and confirmation of your effective date of registration by post, with information about your first VAT return and payment. Then sign up for your VAT online account if you have not already.

While you wait: you cannot show VAT on your invoices until your VAT number arrives, but you can increase your prices to cover the VAT owed from your effective date — then reissue the invoices showing the VAT once your number comes through.

After You Register

From your effective date of registration, you must:

Most businesses are also signed up to Making Tax Digital for VAT — keep records in compatible software.

Sources and references

FAQs

How long does VAT registration take?

HMRC does not give a fixed timescale in its registration guide, so apply as soon as you know you must register — your duties run from your effective date of registration, not from the day your number arrives. HMRC sends your 9-digit VAT number and registration details by post. Until the number arrives you cannot show VAT on your invoices, but you can increase your prices to cover the VAT you will owe, then reissue the invoices once your number comes through.

Can I backdate my VAT registration?

If you should have registered earlier, your registration is backdated automatically: you must pay VAT on all sales made since the date you should have registered. If you register voluntarily below the threshold, you can start charging VAT on your sales and reclaiming VAT on your purchases from your effective date of registration.

What happens if I register late?

You must pay VAT on any sales you have made since the date you should have registered, even if you did not charge your customers VAT at the time. You may also have to pay a penalty, depending on how much VAT you owe and how late your registration is.

Do I need to register if everything I sell is zero-rated?

Zero-rated sales still count towards the £90,000 threshold, so you may still have to register. However, if most of what you sell is zero-rated, you can ask HMRC for an exemption from registration. If HMRC refuses the exemption, they will register you for VAT instead.

Can I cancel my VAT registration later?

Yes. You must cancel your registration if you are no longer eligible to be VAT registered — for example, if you stop trading or stop making taxable supplies. If your taxable turnover falls below £88,000, you can ask HMRC to cancel your registration, but you do not have to.

Ready to work with VAT day to day? Use our free UK VAT calculator to add or remove VAT on any amount instantly.

Related guides: VAT Registration Threshold: The £90,000 Limit Explained · VAT Return: How to Complete and File Yours · How to Calculate VAT at 5% (Reduced Rate)