Winning new customers and seeing your sales grow should feel exciting. But as your business grows, there is one number you need to keep an eye on: your VAT taxable turnover.
For UK-based businesses, the current VAT registration threshold is £90,000. What can catch business owners out is how that threshold is measured. It isn’t simply a figure to check when your annual accounts are prepared.
Your turnover doesn’t reset at year-end
You generally need to register for VAT when your taxable turnover exceeds £90,000 over a rolling 12-month period.
That means checking the previous 12 months at the end of each month, rather than waiting for your company year-end or the end of the tax year. If your business is newer, you look at the period since it started. For example, your accounts might run from April to March, but your taxable sales from November to October could take you over the threshold.
Starting a new accounting year does not reset the VAT calculation.
It’s based on sales, not profit
Another common misunderstanding is that the threshold relates to how much money your business makes after expenses. It doesn’t.
Taxable turnover broadly means the value of sales that are subject to VAT, including zero-rated sales. VAT-exempt sales and sales outside the scope of UK VAT are generally excluded.
A business can therefore have taxable turnover above £90,000 while making a much smaller profit. Your costs do not reduce the turnover figure used for this test.
A large contract can trigger registration sooner
There is also a separate forward-looking rule. If you expect your taxable turnover to exceed £90,000 in the next 30 days alone, you must register under that test. This could become relevant when you secure a substantial new contract.
It is a different test from expecting your sales to exceed £90,000 over the coming year.
Why timing matters
If you exceed the threshold under the rolling 12-month test, you normally have 30 days from the end of that month to register. Registration takes effect from the first day of the second month afterwards. Registering late can mean owing VAT from the date you should have been registered, even if you did not charge it to your customers. A penalty may also apply, which can put pressure on your cash flow, particularly where prices have already been agreed.
What should growing businesses do?
A simple monthly routine can help you spot the issue early:
Keep your sales records up to date.
Review your rolling taxable turnover every month.
Flag significant new contracts before work begins.
Consider how VAT registration could affect your pricing and cash flow.
Checking regularly gives you time to understand your position and plan your next steps.
How Crow Finance can help
At Crow Finance, we provide remote bookkeeping, VAT return support and outsourced finance services for UK businesses.
We help keep your records organised and your figures clear, making it easier to monitor growth and spot when your VAT position needs attention.
Whether you are approaching the threshold or already registered and looking for ongoing support, we can discuss a service that fits your business.
Growing towards the VAT threshold? Contact Crow Finance to discuss your bookkeeping and VAT support.
* Information checked in October 2026. This article covers the general VAT registration rules for UK-based businesses; exceptions and special rules can apply.
Written by Kamila | Director, Crow Finance