Why the VAT threshold deserves your attention early

If you run a small business in the UK, there is a number quietly sitting in the background of every sale you make: the VAT registration threshold. Cross it and you must register for VAT, charge VAT on your taxable supplies and file regular returns. At the time of writing, the threshold is £90,000 of taxable turnover in any rolling 12-month period, with the deregistration threshold set at £88,000. Those figures are reviewed in most Budgets, so check the current position before you make any decisions.

The trap is that the threshold is not measured by your financial year. It follows you around day by day, which catches out plenty of otherwise well-organised owners. Understanding the mechanics now saves you a scramble later.

How the rolling 12-month test actually works

You look back over the previous 12 months, not forward to the end of your accounting period. On the last day of every month, ask yourself a simple question: has my taxable turnover over the last 12 months gone over the threshold? If it has, you must notify the tax authority within 30 days of the end of the month in which you breached it.

There is also a forward look. If you have reasonable grounds to believe your turnover will exceed the threshold in the next 30 days alone — perhaps because you have just signed a large contract — you must register even if the previous 12 months were quiet. Here you notify within 30 days, and your registration generally takes effect from the start of that 30-day period.

The sting is that registration can be backdated. If you register late, you may be liable for VAT on sales where you never charged it, and you cannot always go back to a customer and ask for the extra 20%.

What counts towards your taxable turnover

This is where a lot of confusion lives. Taxable turnover is not your profit, and it is not the money landing in your bank account. It is the total value of your taxable supplies, excluding the VAT itself.

• Standard-rate and reduced-rate sales count in full.
• Zero-rated sales count too. This surprises people. Zero-rated goods such as most food, children's clothing and exported goods still count towards the threshold even though no VAT is charged.
• Exempt sales do not count. Things like certain financial services, insurance, some education and healthcare are outside the scope of the calculation.
• Sales genuinely outside the scope of UK VAT — for example certain services supplied to overseas business customers — are excluded.
• Business asset sales that are taxable supplies count, so selling a piece of equipment you no longer need is not a free pass.
• Wages, bank interest and dividends do not count, because they are not supplies you make.

Is voluntary registration worth it?

You can register before you hit the threshold, and sometimes it is a smart move. If most of your customers are VAT-registered businesses, they can reclaim the VAT you charge, so the price rise is largely neutral for them — while you can reclaim VAT on your own purchases, software, equipment and professional fees.

The downsides are real. You take on record-keeping and filing obligations, digital record-keeping rules apply, and if you sell mainly to consumers, adding 20% to your prices can hurt. A simplification scheme such as the flat rate scheme may reduce the admin, but it does not suit everyone, so run the numbers for your own mix of sales and costs before committing.

Getting your records in order before you notify

Once you know your effective registration date, work backwards. The tax authority will expect clean, accurate records from that date, and the first return often lands sooner than people expect.

• Pin down the exact date your registration starts, then list every sale and purchase from that point.
• Check pre-registration costs. You can usually reclaim VAT on services bought in the six months before registration and on goods still held in stock or used in the business, bought in the four years before.
• Move to digital records if you have not already, as returns must be filed through compatible software.
• Decide your accounting scheme — standard, cash accounting, annual accounting or flat rate — because each changes how and when you report.
• Collect VAT numbers from your suppliers, and clean up your sales invoices so the VAT is shown separately.
• Tell your customers and update your price lists, quotes and website before the change takes effect.
• Put money aside. The VAT you collect is not yours to spend, so a separate pot avoids a nasty surprise at the end of the quarter.

Mistakes that cost small businesses dear

The most common errors are assuming the threshold is based on profit, on your financial year, or on the money you have actually been paid. Others forget that zero-rated sales count, or wait until their accountant mentions it at year end — by which point penalties and backdated VAT can be significant.

If you are close to the threshold, do not wait for the crossing point. Review your rolling turnover monthly, keep your bookkeeping current, and take advice early. A short conversation before you register is far cheaper than sorting out a late notification afterwards.