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VAT threshold checker (UK)

For sole traders and small firms watching their sales. Enter your taxable turnover for each of the last 12 months and see how close you are to the VAT threshold. Nothing you type leaves your browser.

Quick answer: you must register for VAT if your taxable turnover for the last 12 months goes over £90,000, or you expect it to go over £90,000 in the next 30 days alone. Go over at the end of July and you must register by 30 August, with VAT from 1 September. Once registered, you can ask to cancel if turnover is less than £88,000. Source: GOV.UK.

1 · Your last 12 months

Starts on the 12 complete months before this one. Enter taxable sales for each month, before any VAT.

2 · The next 30 days optional

Only for a big one-off, such as a contract worth more than £90,000 on its own.
The day you realised. Starts as today.

Your VAT position

Result–

How the VAT threshold tests work

  1. 12-month test: at the end of each month, add up your taxable turnover for the last 12 months. If it is over £90,000, register within 30 days of the end of that month. You're registered from the first day of the second month after.
  2. 30-day test: if you expect your taxable turnover in the next 30 days alone to go over £90,000, register by the end of those 30 days. You're registered from the start of that period.
  3. Cancelling: if you're registered and taxable turnover is less than £88,000, you can ask to cancel. It's optional.
VAT thresholds
ThresholdFigure
Registration: taxable turnover more than£90,000
Deregistration: taxable turnover less than£88,000
Register within (12-month test)30 days of month end
Register by (30-day test)end of the 30 days

This checker only knows the months you enter. Months before the first one count as £0, so if you had sales before then you may have gone over sooner.

Sources: GOV.UK: when to register for VAT · GOV.UK: VAT thresholds. Rates checked 8 October 2026.

VAT threshold FAQs

What counts as taxable turnover?

Everything you sell that isn't VAT exempt or out of scope. That includes zero-rated and reduced-rate sales, not just standard-rated ones, plus things like goods you hire out, goods you give away or barter, and reverse-charge services.

Source: GOV.UK: when to register for VAT

Is it the tax year or a rolling 12 months?

A rolling 12 months. It isn't your accounting year or the tax year. At the end of every month, add up the last 12 months. If that total goes over £90,000, you have to register. Exactly £90,000 isn't over.

Source: GOV.UK: when to register for VAT · GOV.UK: VAT thresholds

When do I have to register, and when does VAT start?

Within 30 days of the end of the month you went over. Your registration takes effect from the first day of the second month after. GOV.UK's example: go over in July, register by 30 August, and VAT applies from 1 September.

Source: GOV.UK: when to register for VAT

What is the 30-day test?

If you expect to go over £90,000 in the next 30 days alone, say from one big contract, you must register by the end of those 30 days. VAT applies from the start of that 30-day period, not the day you go over. GOV.UK's example: realise on 1 May, register by 30 May, effective 1 May.

Source: GOV.UK: when to register for VAT

What if I only go over once, or my sales drop later?

If you go over temporarily you can ask HMRC for an exception, and they decide. If you're already registered and your taxable turnover is less than £88,000, you can choose to cancel your registration.

Source: GOV.UK: when to register for VAT · GOV.UK: VAT thresholds

What happens if I register late?

You have to pay VAT on the sales you made from the date you should have been registered, even if you didn't charge your customers for it. You might also get a penalty, depending on how much you owe and how late you are.

Source: GOV.UK: when to register for VAT

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