Think you can dodge VAT by keeping turnover under £90,000? The trap is the rolling 12-month test. Many construction subcontractors and e-commerce sellers assume the threshold resets each April. It does not. HMRC looks at your cumulative VAT-exclusive sales across any continuous 12-month window. Hit £90,001 on 15 August? You have until the end of September to notify HMRC, and your effective registration date will be 1 September (or earlier if you request backdating). Miss that deadline and you face penalties equal to a percentage of the VAT you should have charged.
The £90,000 threshold has been frozen since April 2024. It applies to the standard rate scheme, not the Flat Rate Scheme, which has its own separate entry requirements. You must monitor actual turnover, not invoiced amounts or projected figures. If you expect to exceed £90,000 in the next 30 days alone, you must register immediately. Otherwise, the 30-day clock starts at the end of the month you breached. For example, a software company turning over £95,000 by 10 June must register by 31 July, with an effective date of 1 July.
Voluntary registration before hitting £90,000 is common among independent retailers and professional services firms. It lets you reclaim input VAT on significant purchases such as fit-out costs, IT infrastructure, or subcontractor fees. Once registered, you must stay in the scheme for at least 12 months, even if your turnover subsequently drops below the deregistration threshold (£88,000 from April 2024). You cannot simply opt out when it becomes inconvenient.
When this matters: crossing the threshold forces a 20% price increase on your invoices unless you absorb it yourself. If your clients are VAT-registered businesses (most B2B consultancies, manufacturers, and healthcare practices), the extra 20% is reclaimable by them, so it is cost-neutral. But if you sell to consumers or VAT-exempt businesses, the added cost lands on your pricing. Plan your growth trajectory accordingly. Use HMRC's online VAT checker or ask your accountant to run a rolling 12-month turnover report monthly. The £90,000 UK VAT threshold is not a ceiling to fear, but it is a number you must respect.