A business whose taxable turnover passes £90,000 must register for VAT, and the rules on timing are less forgiving than many owners expect. This piece argues that a threshold built as a single step discourages the very growth London’s small firms are told to pursue.
This is an opinion piece. It reflects the views of the author, not an institutional position of London Loves Commerce.
What does the threshold actually require?
According to GOV.UK, businesses have to register for VAT if their VAT taxable turnover is more than £90,000. Two tests apply, and they work in different directions.
The first looks backwards. Once taxable turnover for the previous 12 months goes over £90,000, the business has 30 days after the end of that month to apply. GOV.UK gives an example: cross the line on 15 July, and the application is due by 30 August, with registration effective from 1 September.
The second looks forwards. If an owner realises that turnover will exceed £90,000 within the next 30 days, registration is required by the end of that 30-day period, and the effective date is the day the owner realised, not the day the money arrived. GOV.UK’s example is a contract signed on 1 May: the application is due by 30 May, effective 1 May.
Businesses below the line can also register voluntarily, which is a deliberate choice rather than an obligation.
Why is a step worse than a slope?
A threshold of this kind is a cliff edge. At £89,999 of turnover a business is outside the system. At £90,001 it is inside, with new obligations attached to every sale from the effective date.
Illustrative arithmetic shows the discomfort. Suppose, purely for illustration, a standard VAT charge of 20 per cent on prices, and a retailer selling to consumers who cannot reclaim it. The retailer has two choices once registered: raise shelf prices by 20 per cent, or hold prices and absorb the charge.
| Choice after registering | Price to customer | Effect on retailer |
|---|---|---|
| Hold the price at £100 | £100 | £16.67 goes to tax; retailer keeps £83.33 |
| Raise price to £120 | £120 | Retailer keeps £100, but risks losing sales |
The first row shows that a £100 price including a 20 per cent charge contains £16.67 of tax (£100 divided by 1.2 gives £83.33). A shop with a 10 per cent net margin that absorbs this sees its position vanish. The second row protects the margin but asks the customer to pay a fifth more overnight. Neither option is attractive, and the choice is forced by crossing one line, not by any change in the quality of the business.
Does the cliff edge change behaviour?
This is the hardest claim to prove, and it should be stated with caution. This piece does not rely on a measured count of firms that hold back. The argument is about incentives rather than statistics: any owner who understands the rules can see that the last few thousand pounds of turnover before the line carry a cost out of proportion to their value.
Consider a London sole trader running a market stall or an online shop at £86,000 of turnover. A good autumn could take the business over the line. Taking on another stockist, another event or a bulk order suddenly has a hidden price. Some owners will take the work and register. Others will decline it, delay invoices, or split activities across separate arrangements, and that last route carries its own rule-based risks. The sensible response varies, but the pull exists in every case.
The pull matters in a city where costs are high. Rent, wages and delivery costs already squeeze margins, a pressure this magazine has examined in its coverage of the financial pressures London’s small businesses are navigating. A step in the tax system that bites hardest on thin-margin traders compounds that squeeze.
Isn’t registration just administration?
That is the strongest counter-argument, and it deserves a fair hearing. Defenders argue that firms selling to other VAT-registered businesses are barely affected, because those customers can recover the charge. For those operators, registration is mostly paperwork. Registration can also lend a firm the look of scale to larger buyers, which is why voluntary registration exists at all.
There is a further defence of a high, simple threshold. A single number is easy to explain and easy for HMRC to apply. Lowering it, or smoothing it, would bring in more small traders and more admin. A high line spares the smallest firms from compliance altogether, and that has real value.
Where the defence runs out
The defence works best for business-to-business sellers and worst for consumer-facing ones, and London’s high streets, markets and food traders are heavily consumer-facing. For them, the reclaim benefit is small and the price effect is direct.
The timing rules add a second problem. The forward-looking 30-day test asks a small owner to predict turnover, often from a single contract or season, and to act on that prediction on the day. A large firm has finance staff for that. A sole trader with a growing order book may have only a spreadsheet and a good week. Missing the effective date is not an abstract risk, because the registration date is fixed by the rules rather than by when the owner got round to it.
A gentler design is easy to describe even if it is hard to legislate. A tapered relief, in which the charge phases in across a band of turnover rather than switching on at once, would remove the cliff. Alternatively, a longer notice window for owners whose turnover is rising steadily would reduce the penalty for honest forecasting errors. Neither exists in the rules as they stand, and nothing in the published GOV.UK guidance suggests either is planned, so owners should plan on the current system.
What growing firms can do with the current rules
The following is general information, not advice:
- Track rolling 12-month taxable turnover monthly, not annually, because the backward test is a rolling one.
- Watch for large single contracts, since the forward test can be triggered by one signature.
- Decide in advance how a price rise would be presented to customers, instead of improvising in the month registration lands.
- Remember that voluntary registration is allowed below the line, which some businesses selling to other firms may find useful.
Owners thinking about wider growth costs may also find it useful to read this magazine’s guide to what business owners should understand about cash flow, since the first VAT quarter changes the shape of the bank balance as well as the price list. Those weighing up wider commercial expansion can set this alongside what small businesses need to get right in London’s market.
A line that should bend rather than snap
VAT will always need a threshold somewhere, and £90,000 is the figure GOV.UK currently gives. The complaint here is about shape, not level. A rule that switches on in full at one pound of turnover rewards stalling, penalises the thin-margin trader, and asks the least-resourced owners to forecast sharply. Turning the cliff into a slope would keep the administrative simplicity its defenders prize while ending the quiet discouragement of growth.
General information only, not tax, legal or financial advice. Thresholds and rules change, so check current official guidance.
Sources: GOV.UK
