Do I Need to Register for VAT in the UK? (Threshold, Rules & Examples)

If you're running a small business in the UK and your income is starting to grow, VAT registration is probably a question you've Googled at least once. Do you have to register? When exactly? And what happens if you don't?

This guide walks you through everything: the current threshold, how it's calculated, real examples, and when it might actually make sense to register even if you don't have to.

What is VAT and why does it matter?

VAT (Value Added Tax) is a tax charged on most goods and services sold in the UK. As a VAT-registered business, you collect VAT from your customers on behalf of HMRC, claim back VAT you've paid on business purchases, and settle the difference with HMRC regularly. The key point: VAT isn't a cost to your business directly; it's passed through to the final consumer. But once you're registered, it changes how you price, invoice, and report.

What is the current VAT registration threshold?

The current VAT registration threshold in the UK is £90,000 in taxable turnover over any rolling 12-month period. This was increased from £85,000 to £90,000 on 1 April 2024, the first increase in seven years. It remains at £90,000 for the 2025/26 tax year, and as of writing, there are no confirmed plans to change it for 2026. At £90,000, the UK's VAT threshold is the joint highest in the OECD (alongside Switzerland), meaning most UK small businesses have a generous buffer before registration becomes compulsory.

How is the £90,000 threshold calculated?

This is where many business owners get caught out. The threshold is not based on your annual accounting year or tax year. It's calculated on a rolling 12-month basis. That means HMRC looks at any consecutive 12-month period, not just January to December or April to March. If your total taxable turnover across any 12-month window exceeds £90,000, you've crossed the threshold.

Example 1 — Gradual growth
A freelance designer earns around £7,000–£8,000 per month. By the time she checks her rolling 12-month total in November, it's reached £91,000, but no single month stood out as unusual. She's crossed the threshold and must register.

Example 2 — Large one-off contract
A small construction firm wins a £95,000 contract in May. Even if the rest of the year is quiet, they know on 1 May that their taxable turnover will exceed £90,000 within the next 30 days. They must apply to register within 30 days of that date.

Example 3 — Seasonal spike
An events photographer has a bumper summer season. By August, their rolling 12-month turnover tips over £90,000. Even though they expect earnings to drop in autumn, the threshold has been crossed, and registration is required.

When exactly must I register?

There are two trigger conditions for mandatory VAT registration:

Condition 1 — Looking back: At the end of any calendar month, if your taxable turnover in the past 12 months has exceeded £90,000, you must register within 30 days of the end of that month. Your effective registration date will be the first day of the following month.

Condition 2 — Looking forward: If at any point you expect your taxable turnover to exceed £90,000 within the next 30 days alone (e.g. you've just signed a large contract), you must register immediately. Your effective registration date is the start of that 30-day window.

Practical example of Condition 1 (from HMRC):
Your rolling 12-month total passes £90,000 on 15 July. You must register by 30 August. Your VAT registration takes effect from 1 September.

What counts as "taxable turnover"?

Taxable turnover is the total value of goods and services you sell in the UK that are subject to VAT, whether at the standard rate (20%), reduced rate (5%), or zero rate (0%).

What's included:

• Most products and services you sell to UK customers
• Zero-rated sales (e.g. most food, children's clothing, books) — these still count toward the threshold even though VAT is charged at 0%

What's excluded:

• VAT-exempt supplies (e.g. financial services, insurance, education, certain health services)
• Sales made outside the scope of VAT (e.g. wages, donations)

Important: Zero-rated and VAT-exempt are not the same thing. Zero-rated sales count toward the £90,000 threshold. Exempt sales do not. If all your sales are genuinely VAT-exempt, you may not need to register at all.

What is the VAT deregistration threshold?

If your taxable turnover drops below £88,000, and you expect it to remain below that level for the next 12 months, you can apply to HMRC to deregister for VAT. The deregistration threshold is deliberately set £2,000 lower than the registration threshold to prevent businesses from constantly crossing in and out of VAT registration due to minor fluctuations. Once deregistered, you must stop charging VAT immediately, submit a final VAT return, and may need to account for VAT on any business assets or stock you're holding if their total value exceeds £1,000.

What if my turnover only temporarily crosses the threshold?

If your taxable turnover temporarily exceeds £90,000, for example, due to an unusually large order or a seasonal spike, you may be able to apply for a registration exception. To do this, you need to contact HMRC and provide evidence that your turnover is unlikely to exceed the deregistration threshold of £88,000 over the next 12 months. HMRC will review your case and either grant the exception in writing or register you for VAT regardless.

Can I register for VAT voluntarily?

Yes. You can register for VAT at any time, even if your turnover is well below £90,000.

Reasons to register voluntarily:

1. Reclaim VAT on business expenses. If you're spending significantly on equipment, premises, supplies, or services that include VAT, voluntary registration lets you reclaim that input tax. For capital-heavy businesses, this can be a meaningful saving.
2. Appear more established to larger clients. Many larger businesses and public sector organisations expect to see a VAT number on invoices. Registering voluntarily signals that your business is credible and properly set up — which can open doors.

3. Future-proof your pricing. If you're close to the threshold, registering voluntarily gives you control over when you transition — rather than scrambling to adjust pricing mid-contract when you unexpectedly cross the line.

Reasons not to register voluntarily:

• If your customers are mostly end consumers (not VAT-registered businesses), adding 20% VAT to your prices makes you less competitive
• VAT compliance carries administrative overhead, digital record-keeping, regular VAT returns, and Making Tax Digital obligations
• You'll need to charge VAT on all your taxable sales from your registration date

What happens if I don't register when I should?

Missing the registration deadline is a compliance failure with real consequences. HMRC can charge penalties based on how late you are and whether they consider the failure to be careless or deliberate. If HMRC discovers the error before you disclose it, penalties tend to be higher. Voluntarily disclosing a late registration and cooperating fully typically results in a more favourable outcome. One important practical issue: HMRC can backdate your registration to the date you should have registered. That means you may owe VAT on sales you've already made, even if you didn't charge it to customers. You'll need to pay that out of your own pocket.

VAT rates in the UK

Once registered, the rate you charge depends on what you're selling:

Making Tax Digital (MTD) for VAT

If you're VAT-registered, you must comply with Making Tax Digital for VAT. This means:

• Keeping digital records of your VAT transactions
• Using MTD-compatible software to submit your VAT returns directly to HMRC

HMRC no longer accepts VAT returns submitted through the older online portal for most businesses. MTD-compatible accounting software, or a platform like Built For Small Business, handles this automatically.

How to register for VAT

Registration is done online through HMRC's VAT registration service. It typically takes around 10 to 15 minutes to complete. You'll receive your VAT registration number within 2 to 3 weeks.

You'll need to provide:

• Your business name and address
• Details of your business activities
• Your estimated turnover
• Your bank account details (for potential VAT repayments)

If you prefer, you can also register by post using form VAT1.

Summary: Do you need to register?

Track your turnover and stay compliant with Built For Small Business

Staying on top of your rolling 12-month turnover is the single most important thing you can do to avoid a surprise VAT registration deadline. Built For Small Business helps UK small businesses track invoices, expenses, and income in one place so you always know where you stand. It's completely free to use. No subscription, no hidden fees.

Start tracking your business for free on builtforsmallbusiness.com

This article is for general information purposes only and does not constitute tax or legal advice. VAT rules can be complex depending on your specific circumstances. We recommend speaking with a qualified accountant or tax adviser if you're unsure about your obligations.

Last updated: April 2026