VAT Calculator

UK invoices, quotes and price lists use a lot of different words for only two numbers. Knowing which is which stops most VAT mistakes before they happen.

So “£250 ex VAT” means £250 is the net figure and VAT still has to be added — you will actually pay £300. “£300 inc VAT” means VAT is already in the £300.

Subtract VAT, minus VAT, reverse VAT, backwards VAT

These four phrases all describe the same single operation: starting from a VAT-inclusive total and working out what the price was before VAT. Whether you call it a subtract VAT calculator, a minus VAT calculator, a reverse VAT calculator or working VAT backwards, the maths is identical — set the mode above to Remove VAT and enter your gross figure.

The important thing is that you divide rather than subtract. To take VAT off a gross amount at the 20% standard rate you divide by 1.2, not take 20% away. Subtracting 20% from £120 gives £96, which is wrong — the correct net figure is £100. Our guide on how to work out VAT backwards explains why in full.

A quick reference

VAT (Value Added Tax) is a consumption tax charged on most goods and services in the UK. Prices are quoted either net (excluding VAT), gross (including VAT), or as the VAT amount itself — and converting between the three is where most mistakes happen. This calculator handles both directions: adding VAT to a net figure, and reverse-calculating (removing) VAT from a gross figure.

Adding VAT to a net amount

Multiply the net amount by 1 + the VAT rate. At the 20% standard rate that means net × 1.2. So £100 net becomes £120 gross, of which £20 is VAT. At the 5% reduced rate, multiply by 1.05.

Removing VAT (reverse VAT) from a gross amount

This is the step people most often get wrong. To work out VAT backwards you divide the gross amount by 1 + the rate — you do not subtract the percentage. At 20%: £120 gross ÷ 1.2 = £100 net, so the VAT is £20. Subtracting 20% from £120 would incorrectly give £96. The VAT fraction shortcut for the 20% rate is 1/6 of the gross figure.

UK VAT rates

There are three rates: the standard rate (20%) applying to most goods and services; the reduced rate (5%) covering things like domestic fuel and power, children's car seats, and certain energy-saving materials; and the zero rate (0%) covering most food, books, newspapers, and children's clothing. Zero-rated is not the same as exempt — zero-rated sales still count toward your VAT-taxable turnover, exempt sales do not.

This tool is for quick everyday calculations. Special schemes — the Flat Rate Scheme, margin schemes, partial exemption, and the domestic reverse charge for construction — follow different rules, so check HMRC guidance or speak to an accountant for those. Nothing here is tax advice.