VAT Threshold Calculator
Check the rolling 12-month £90,000 VAT registration threshold and find your exact registration dates
Last updated: June 2026
VAT Threshold Checker (2026/27)
Enter your VAT taxable turnover for each of the last 12 months (oldest first). The tool slides a rolling 12-month window and flags the first month your cumulative taxable turnover went over the £90,000 registration threshold. You can also run the optional forward-look 30-day test below.
Used to label the breach month and work out your notify-by and effective registration dates.
If you expect to take more than £90,000 in taxable turnover in just the next 30 days (e.g. a big one-off contract), enter that expected amount.
What this calculator does
The VAT threshold calculator helps UK sole traders, partnerships and limited companies work out exactly when they must register for VAT. Unlike a simple "are you over £90,000?" check, HMRC's real test is a rolling 12-month one: at the end of every single month you must look back over the previous 12 months of VAT taxable turnover and check whether the running total has gone over £90,000. Most small businesses miss the registration deadline because they think in terms of their accounting year, not a sliding window.
This tool does that month-by-month for you. You enter your taxable turnover for each of the last twelve months, and it slides the 12-month window forward, finds the first month the cumulative total breached £90,000, then tells you your legal notify-by date and your effective date of registration. It also runs the separate forward-look 30-day test and tells you whether your turnover has dropped below the £88,000 deregistration threshold. It is built for owners, bookkeepers and accountants who want a fast, accurate sanity check before contacting HMRC.
How it works
- Registration threshold — £90,000: If your total taxable turnover for the last 12 months goes over £90,000, you must register. The tool checks the rolling total at the end of each month.
- Notify-by date: You must tell HMRC within 30 days of the end of the month in which you went over the threshold.
- Effective date of registration: Your VAT registration takes effect from the first day of the second month after you went over the threshold.
- Forward-look 30-day test: You must also register if you expect your taxable turnover to go over £90,000 in the next 30 days alone. Here you must register by the end of that 30-day period, and the effective date is the date you realised you would breach.
- Deregistration threshold — £88,000: If your taxable turnover falls below £88,000 you can apply to cancel your VAT registration.
Worked example
Imagine a business whose Month 1 is January 2025. Its taxable turnover is a steady £7,000 a month from January to October (10 × £7,000 = £70,000), then jumps to £12,000 in November and £12,000 in December because of Christmas trade.
Rolling 12-month total after December = £70,000 + £12,000 + £12,000 = £94,000, which is over £90,000. The breach month is December 2025. The notify-by date is 30 days after the end of December — i.e. 30 January 2026. The effective date of registration is the first day of the second month after December, which is 1 February 2026. The calculator returns all three dates automatically.
Frequently asked questions
What counts as VAT taxable turnover?
It is the total value of everything you sell that is not VAT exempt or out of scope — including standard-rated, reduced-rated and zero-rated sales. It excludes VAT-exempt supplies (such as some financial services) and the sale of capital assets. Always use these taxable figures, not your total bank income.
Is the threshold based on my accounting year?
No. HMRC uses a rolling 12-month period that is recalculated at the end of every month, not your accounting or tax year. That is why this tool slides the window month by month.
What happens if I register late?
You must still account for VAT from your effective date of registration, even if you register late, and you may have to pay what you owe plus a potential penalty. Always check the rolling total monthly to avoid this.
Can I deregister if my turnover falls?
Yes. If your VAT taxable turnover for the next 12 months is expected to be below the £88,000 deregistration threshold, you can ask HMRC to cancel your registration.
Source: Figures verified against HMRC / GOV.UK guidance — VAT registration: when to register (GOV.UK) and VAT thresholds (GOV.UK). This tool is for guidance only and is not a substitute for professional advice.
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