When Should You Register for VAT? A Practical Guide for Small Businesses (2026 to 2027)
VAT registration is one of the areas where business owners most often come to us after something has already gone wrong. They have registered too late, registered when they did not need to, or picked a VAT scheme that does not suit how their business operates. Each of these mistakes has a real cost, whether that is a surprise tax bill, a penalty from HMRC, or a cash flow problem that could have been avoided with a bit of early planning.
This guide walks you through when VAT registration becomes a legal requirement in the UK for the 2026 to 2027 tax year, what to watch out for as your turnover grows, and how to approach the decision properly so it does not catch you off guard.
The VAT Registration Threshold
For the 2026 to 2027 tax year, the VAT registration threshold remains £90,000. This figure is based on your taxable turnover, not your profit. That distinction matters more than you might think. Taxable turnover covers most goods and services you sell, but it does not include everything that lands in your business bank account. Grants, loan receipts, and certain exempt sales, for example, would not count.
You are legally required to register for VAT if either of the following applies to you:
- Your taxable turnover exceeds £90,000 in the previous 12 months.
- You expect your taxable turnover to exceed £90,000 in the next 30 days alone.
The first test is a rolling 12-month test. It is not based on your accounting year or your tax year, and this is where a lot of business owners trip up. You need to be looking back over the previous 12 months at the end of every single month, not just at year end.
To put it plainly: if your turnover from July 2025 to June 2026 exceeds £90,000, you are required to register, even if your turnover for the April to April tax year looks lower on paper.
Once you cross the threshold, you have 30 days to register with HMRC. Your VAT registration will then normally take effect from the first day of the month after that deadline.
What Happens If You Register Late
Registering for VAT late is one of the costliest mistakes we see, and it is entirely avoidable. If HMRC determines that you should have registered earlier, they can backdate your registration and require you to pay the VAT on those historic sales, even if you never collected it from your customers.
Here is a straightforward example. If you should have registered six months ago and invoiced £50,000 in that period, HMRC can still come to you for the VAT element on those sales. That works out to £8,333 you would need to pay from your own pocket, because your customers were never charged it in the first place.
This is why we always recommend that business owners track their rolling 12-month turnover every month, not just when they feel like things are getting busy.
Voluntary VAT Registration
You can register for VAT voluntarily even if your turnover is below £90,000. It is a decision that makes sense for some businesses and not at all for others, so it is worth understanding the reasoning before making a call either way.
Voluntary registration is worth a conversation with your accountant if:
- Your customers are VAT-registered businesses, because they can reclaim the VAT you charge them, and your pricing stays competitive
- You have significant VAT-bearing expenses, such as equipment, materials, or subcontractors, and you want to reclaim that input tax
- You want your business to appear more established, as VAT registration can signal credibility to larger clients and suppliers
- Your turnover is heading toward £80,000 or more and you want to plan ahead rather than be forced into it at short notice
That said, voluntary registration is not always the right move. If you sell directly to the public or to smaller businesses that cannot reclaim VAT, adding 20% to your prices can put you at a real disadvantage against competitors who are not yet registered.
The right answer depends on your specific customer base, your margins, and your growth plans. It is not a one-size-fits-all decision.
Choosing the Right VAT Scheme
Getting registered is only the first step. The scheme you register under will affect how much VAT you actually pay, how you account for it, and how it sits with your cash flow. Getting this wrong can be an expensive oversight.
Common schemes for small businesses include:
Standard VAT Accounting
You pay HMRC the difference between VAT charged on sales and VAT paid on expenses.
Flat Rate Scheme
Rather than tracking VAT on every individual sale and purchase, you pay HMRC a fixed percentage of your gross turnover and keep the difference. This can reduce your VAT bill and cut down on admin, but the rules have tightened considerably in recent years. Service-based businesses in particular often find it is no longer as attractive as it once was.
Cash Accounting Scheme
Instead of paying VAT based on when you raise an invoice, you only account for it when the money actually arrives in your account. For businesses that deal with slow-paying clients or work on extended payment terms, this can make a meaningful difference to cash flow.
Choosing the wrong scheme can cost you thousands over time. It is one of those decisions that looks minor at the point of registration but compounds quickly, so it is worth taking the time to model it out properly before you commit.
Signs You Should Be Thinking About VAT Registration Soon
Do not be a business owner who waits until you cross the threshold before thinking about VAT, as by then it is often too late to plan properly.
Here are some warning signs that you should start discussing VAT:
- Your rolling 12-month turnover is sitting between £75,000 and £85,000
- Your revenue has grown noticeably in the past three to six months
- You are starting to win larger contracts that could push your turnover up significantly
- You are working with larger businesses or public sector clients that expect their suppliers to be VAT registered
- You are spending a meaningful amount on VAT-bearing costs that you currently cannot reclaim
Getting ahead of it gives you time to review your pricing structure, understand the impact on your margins, and decide whether voluntary registration makes sense before the decision is made for you.
VAT and Pricing
A concern we hear regularly is that VAT registration automatically means putting prices up by 20%. That is not always true, but it does depend heavily on who your customers are and how your margins are structured.
If you sell to other VAT-registered businesses, the VAT you charge is effectively invisible to them, because they reclaim it from HMRC. Your net price to them stays the same. If you sell to consumers or unregistered businesses, the VAT comes straight out of their pocket, which means your prices go up in real terms unless you absorb some or all of it yourself.
This is why VAT registration is not just a tax compliance question. It is a commercial decision that affects your pricing, customer relationships, and market competitiveness.
Final Thoughts
VAT registration is not just a box to tick. It is a decision with real financial consequences in both directions. Register too late and you could be facing backdated VAT bills and HMRC penalties. Register without thinking it through and you could be handing a pricing advantage to your competitors or squeezing your own margins unnecessarily.
We advise the following steps: track your rolling turnover monthly, understand where the threshold sits relative to your current trajectory, and start the VAT planning conversation well before you are legally required to register.
If you are not sure whether you need to register, whether voluntary registration would benefit you, or which VAT scheme fits your business model, get advice from us before you need to act. The earlier you plan, the more options you have.