If you run a business in the UK — whether as a sole trader, a partnership, or a limited company — it’s crucial to understand when VAT registration becomes mandatory. While some businesses choose to register voluntarily, others are legally required to do so once their turnover hits a certain threshold.
In this guide, we’ll break down the rules around when to register for VAT, how to calculate taxable turnover, what to do if you’re approaching the limit, and how to register properly.
When Must You Register for VAT?
You must register for VAT if:
- Your taxable turnover exceeds £90,000 in any rolling 12-month period
- You expect your taxable turnover to exceed £90,000 in the next 30 days alone
This applies to all businesses based in the UK, regardless of their legal structure.
Additionally, if you and your business are based outside the UK but you supply goods or services to the UK (or intend to do so within the next 30 days), you must register for VAT immediately, even if your turnover is below the threshold.
What Counts as Taxable Turnover?
Taxable turnover includes any goods or services you sell that aren’t VAT-exempt. This means it includes:
- Standard-rated items (20%)
- Reduced-rate items (5%)
- Zero-rated goods (0%)
It also includes some less obvious types of income, such as:
- Goods loaned, hired, or gifted to customers
- Personal use of business goods
- Barter or part-exchange transactions
- Services received from abroad (subject to the reverse charge)
- Domestic reverse charge items (e.g. some construction services)
- Building work over £100,000 carried out by the business itself
To avoid miscalculations, it’s important to assess all sources of taxable income, not just cash sales or invoices raised.
What Are the Deadlines?
If your taxable turnover exceeds £90,000 over the past 12 months, you must:
- Register for VAT within 30 days of the end of the month in which you crossed the threshold
- Your VAT registration takes effect from the first day of the second month following that
Example:
Bella, a sole trader, sees her taxable turnover exceed £90,000 on 7 July 2025.
She must register by 30 August 2025, and her VAT registration is effective from 1 September 2025.
If you expect to exceed £90,000 in just one 30-day period, you must:
- Register by the end of that 30-day window
- Your registration becomes effective on the date you realised the threshold would be exceeded
Example:
Cameron signs a contract worth £102,000 on 17 July 2025.
He must register by 16 August 2025, and his VAT registration takes effect immediately on 17 July. He must charge VAT on this sale.
What If You Register Late?
If you miss the registration deadline:
- You will owe backdated VAT on all taxable sales made after the date you should have registered
- You may also be liable for late registration penalties
That’s why it’s essential to monitor your turnover carefully and act quickly once the threshold is breached.
What If You Only Temporarily Exceed the Threshold?
If your taxable turnover goes over £90,000 briefly (e.g. due to one large order), but you can show it will fall back below the limit, you can apply for a registration exception.
You’ll need to provide written evidence and an explanation of why your turnover is unlikely to remain above the threshold.
HMRC will decide whether to grant the exception — if not, you’ll be required to register.
How to Register for VAT
You can register for VAT online via the official HMRC portal:
👉 Register for VAT
You’ll need to provide different information depending on how your business is set up:
✅ For Sole Traders and Partnerships:
- National Insurance Number
- Identity document (e.g. passport)
- Bank account details
- Unique Taxpayer Reference (UTR)
- Actual turnover and estimated turnover for the next 12 months
✅ For Limited Companies:
- Company registration number
- Business bank account details
- UTR
- Annual turnover figures
- Estimate of next year’s taxable turnover
In some cases — such as applying for the Agricultural Flat Rate Scheme — registration must be done by post rather than online.
Can You Register Voluntarily?
Yes. Even if your turnover is below £90,000, you can choose to register voluntarily.
This might be worthwhile if:
- You sell mainly to VAT-registered businesses (who can reclaim the VAT you charge)
- You make zero-rated sales (so you charge 0% VAT but can still reclaim VAT on purchases)
Voluntary VAT registration can also enhance your professional image and help with cash flow planning, especially if your business has significant VATable expenses.
Final Thoughts
Understanding when and how to register for VAT is essential for staying compliant — and avoiding costly penalties. Whether you’ve already crossed the threshold or want to register voluntarily, the process is straightforward if you prepare the right information.
If you need help calculating your turnover, deciding whether to register, or completing the online forms, the team at Yorkshire Accountancy is here to make the process simple and stress-free.
Partner note: VAT Notice 700/1.
