VAT registration, rates and the Flat Rate Scheme

Test turnover on a rolling basis

The compulsory registration threshold is tested against taxable turnover over a rolling 12-month period, not just a business’s accounting year or calendar year. Businesses also need to consider whether they expect taxable turnover to exceed the threshold in the next 30 days alone. GOV.UK explains both tests and the deadlines for notifying HMRC.

Taxable turnover generally includes standard-rated, reduced-rated and zero-rated supplies, but not exempt supplies. That distinction matters: a zero-rated sale can count towards registration even though its VAT rate is zero. A business with both exempt and taxable activity may face partial-exemption issues that a simple calculator cannot resolve.

Rates describe different treatments

The standard VAT rate applies to many goods and services; a reduced rate or zero rate applies only where the rules say it does. Exemption is not the same as zero rating. A zero-rated sale remains taxable at a zero rate, whereas exemption generally limits recovery of related input VAT. Verify classification against the official VAT notice for your sector before changing invoice templates.

For illustration, adding a hypothetical 20% VAT rate to £100 net gives £20 VAT and £120 gross. Removing that same rate from £120 gross gives £120 ÷ 1.20 = £100 net and £20 VAT; subtracting 20% of £120 would be wrong. The standard 20% rate is published on GOV.UK, but check the latest rate and whether your transaction qualifies.

Understand what registration changes

A VAT-registered business ordinarily charges VAT on taxable sales and may recover eligible VAT on business purchases under the applicable rules. The amount paid to HMRC is generally output VAT less recoverable input VAT, subject to the scheme and period. VAT collected from customers is not simply extra profit.

Registration brings record-keeping and return requirements, including digital record rules where applicable. Voluntary registration can be useful in some business-to-business settings but could make prices less competitive for customers who cannot reclaim VAT. The result depends on your customers, costs and business structure, not just whether turnover is close to a threshold.

How the Flat Rate Scheme differs

The Flat Rate Scheme calculates VAT paid to HMRC using a percentage of VAT-inclusive turnover determined by the business category, with special considerations for limited-cost businesses. That percentage is not the VAT rate you show on customers’ invoices. Eligibility and exit limits are separate from compulsory registration; check the current official scheme guidance before joining.

The scheme generally restricts input VAT recovery, with specific exceptions such as qualifying capital assets. It is not always cheaper than standard accounting. Model real expected sales and purchases across a period rather than comparing two headline percentages. A VAT add/remove calculator is useful for an invoice but is not a Flat Rate Scheme eligibility checker.

Worked example: VAT-inclusive pricing

Suppose a standard-rated service is priced at £250 net, with the published standard VAT rate of 20% applying. VAT is £250 × 0.20 = £50 and the gross invoice is £300. If you only know the gross figure, £300 ÷ 1.20 = £250 net and the difference is £50.

The £50 collected is output VAT, not automatically the VAT the business ultimately pays after eligible input VAT or a scheme calculation. If the service actually qualifies for another rate or is exempt, the arithmetic needs different treatment. Confirm classification with official guidance before issuing an invoice.

Frequently asked questions

Official sources

• VAT rates
• VAT registration thresholds
• VAT Flat Rate Scheme

Check the linked official guidance for the latest figures before making a decision.

Related calculators

• VAT Calculator
• Percentage Calculator
• Self-Employed Tax Calculator