Knowing how to register VAT in the UK is one of those things that can catch a growing business off guard. You’re heads-down building your revenue, and then you realise — often without much warning — that you’ve crossed or are about to cross the threshold. At that point, the clock starts ticking.

As of June 2026, the VAT registration threshold remains £90,000 in taxable turnover. That figure hasn’t changed recently, but the rules around when to register and what happens if you miss it are stricter than many business owners realise. HMRC recorded over 234,000 new VAT registrations in 2024–25 alone — so you’re in very good company if you’re going through this for the first time.

This guide covers who needs to register, how the threshold actually works (it’s not as simple as your annual accounts figure), what documents you’ll need, how to complete the process online, and what schemes might be worth considering once you’re registered. Where there are genuine judgement calls or edge cases, we’ll flag them clearly.

VAT registration is compulsory once your taxable turnover exceeds £90,000 in any rolling 12-month period. Crucially, this is not your financial year — it’s any 12-month window running backwards from today. If your turnover from 1 June 2025 to 31 May 2026 exceeds £90,000, you need to register, regardless of what your last set of accounts said.

This catches a significant number of businesses out. Research suggests around 68% of new UK SMEs underestimate their turnover because they think in annual accounting terms rather than rolling 12-month terms. A seasonal business, for example, might look comfortably under the threshold at year-end but breach it mid-year once a strong quarter is included in the rolling total.

Voluntary registration

Even if you’re below £90,000, you can choose to register voluntarily. There are scenarios where this makes sense — particularly if your customers are predominantly VAT-registered businesses themselves, because they can reclaim the VAT you charge them and it costs them nothing. Voluntary registration also lets you reclaim VAT on your own purchases, which can be meaningful if you spend a lot on equipment, materials, or subscriptions.

Exempt and zero-rated supplies

Not all turnover counts towards the threshold in the same way. Zero-rated supplies (such as most food, children’s clothing, and books) do count towards your taxable turnover for registration purposes — they’re taxable at 0%, not exempt. Exempt supplies (such as most financial services, insurance, and residential lettings) do not count. The distinction matters, so if your business spans both types it’s worth checking carefully.

The GOV.UK guidance on VAT registration is the authoritative source for specific supply types.

The timing rules for VAT registration are precise, and missing them carries real cost. Here’s how it works:

The historical test (already exceeded)

At the end of each calendar month, look back at your turnover for the previous 12 months. If it exceeds £90,000, you must apply to register within 30 days of the end of that month. Your effective registration date is then the first day of the second month after you exceeded the threshold.

For example: if your rolling 12-month turnover exceeds £90,000 as measured at the end of April 2026, you have until 30 May 2026 to apply. Your effective VAT registration date would be 1 June 2026.

The future test (expecting to exceed)

There’s a second trigger that catches some businesses entirely off guard. If at any point you expect your taxable turnover to exceed £90,000 within the next 30 days alone — perhaps because you’ve just secured a large contract — you must register by the end of that 30-day period. Your effective date is the day you first realised this was going to happen, not the day you applied.

This future test is particularly relevant for project-based businesses and contractors who land occasional large engagements.

What happens if you miss the deadline

Late registration is not a minor administrative slip. HMRC will require you to account for VAT on all your sales dating back to the date you should have been registered — whether you collected that VAT from customers or not. On top of that, penalties start at £100 plus 5% of the VAT owed, rising to 10% if you’re between three and six months late, and up to 15% for delays of more than six months. You bear the cost, not your customers.

Before you sit down to complete your VAT registration, it saves time to have everything to hand. HMRC’s online process is reasonably straightforward, but stopping mid-way to track down documents can create complications.

For sole traders and partnerships

• Government Gateway user ID (create one if you don’t have it)
• National Insurance number
• Identity documents (passport or driving licence)
• Business bank account details
• Unique Taxpayer Reference (UTR) — if you have one from Self Assessment
• Details of your business turnover: actual figure for the past 12 months and your estimate for the next 12

For limited companies

• Government Gateway user ID linked to the company
• Company registration number from Companies House
• Business bank account details
• Corporation Tax UTR (if already trading)
• Annual turnover to date and projected turnover for the next 12 months

If your company doesn’t yet have a Government Gateway account set up for business taxes, you’ll need to create one before you can access the VAT registration service. This is a separate process to your personal Gateway account.

A note on projected turnover

HMRC will ask for your estimate of turnover for the next 12 months. Be honest and reasonable here — this isn’t a binding commitment, but wildly inaccurate figures can create administrative difficulties later, particularly if you’re considering a VAT scheme where turnover thresholds apply.

Once you’re registered, you don’t automatically have to use HMRC’s standard VAT accounting method. Several schemes are available that can make VAT administration significantly simpler — or, in some cases, financially beneficial.

Flat Rate Scheme

Designed for small businesses with taxable turnover under £150,000, the Flat Rate Scheme lets you pay a fixed percentage of your gross (VAT-inclusive) turnover to HMRC rather than calculating the difference between VAT charged and VAT reclaimed. The rate varies by industry and typically sits between 4% and 14.5%.

There’s a useful incentive for new VAT registrants: in your first year of VAT registration, the flat rate is reduced by 1 percentage point, which can create a small but genuine cash flow benefit. Whether the scheme works in your favour depends on how much VAT you incur on purchases — businesses with low input VAT costs tend to benefit most.

Cash Accounting Scheme

Under standard VAT accounting, you account for VAT when you invoice, even if your customer hasn’t paid yet. This is a well-known cash flow pressure point for SMEs — you can end up paying HMRC before the money has actually hit your account. The Cash Accounting Scheme resolves this by letting you account for VAT only when payment is received (and reclaim it only when you’ve paid your suppliers). It’s available to businesses with taxable turnover under £1.35 million.

Annual Accounting Scheme

Instead of submitting quarterly VAT returns, you submit one return per year and make advance payments throughout. This reduces admin but requires careful cash flow planning. It suits businesses with stable, predictable turnover.

The right scheme depends on your trading model, your customers, and how you manage cash. There’s no single correct answer.

Once HMRC processes your application, you’ll receive a VAT registration certificate confirming your 9-digit VAT number, your effective registration date, and the date your first VAT return is due. Processing typically takes around two weeks, though it can be longer during busy periods.

Charging VAT before your number arrives

There’s an important practical point here that trips some businesses up. Your obligation to charge VAT starts from your effective date of registration — but you cannot show a VAT number on invoices until your certificate arrives with the actual number. In the meantime, you can increase your prices to account for VAT, and once your number comes through, you can reissue VAT invoices covering that period. Keep clear records of sales made during this gap.

Making Tax Digital for VAT

All VAT-registered businesses are now required to comply with Making Tax Digital (MTD) for VAT. This means keeping digital records and submitting VAT returns using MTD-compatible software — you can no longer file manually through your HMRC online account. Cloud accounting software such as Xero, QuickBooks, or FreeAgent handles this automatically, which is one reason many businesses move to cloud bookkeeping around the time of VAT registration.

VAT return frequency and payment

Most businesses file VAT returns quarterly, with payment due one month and seven days after the end of each quarter. Setting up a Direct Debit through your HMRC business tax account is the simplest way to ensure payments go out on time. Late payment carries interest charges and, in persistent cases, surcharges.

The registration itself is completed through HMRC’s online service. Here’s what to expect at each stage.

Most VAT registration problems are avoidable — here are the ones we see most frequently in practice.