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Tax year: Current UK VAT ratesJurisdiction: UKLast verified: June 6 2026

VAT Calculator

Add VAT to a net price, remove VAT from a gross price, or check the VAT element on an invoice line. The calculator handles the standard 20% rate, the reduced 5% rate, zero-rated supplies, and custom rates for older invoices or unusual checks.

Calculate VAT on a price or invoice line

Choose whether the amount you entered is before VAT or already includes VAT.

Add VAT to net, remove VAT from gross, or show the VAT element.

£

Net amount when adding VAT; gross amount when removing VAT.

Use 1 for a single amount, or add a quantity for repeated items.

Useful when checking accounting software or supplier invoices.

Standard VAT

20%

The rate for most UK goods and services.

Reduced VAT

5%

Used only for specific supplies that meet the conditions.

20% VAT fraction

1/6

The VAT part of a gross 20% price is one sixth of the total.

The VAT job this calculator is built for

VAT maths is simple when you know which direction you are going. If you start with a net price, you add VAT on top. If you start with a VAT-inclusive price, you divide by the VAT multiplier to find the net amount. The mistake that catches people out is taking 20% off a gross price. On a GBP 120 gross price at 20% VAT, the VAT is GBP 20, not GBP 24.

Use this calculator for quoting, checking supplier invoices, sense-checking bookkeeping entries, splitting a gross card receipt, or comparing what a price looks like before and after VAT. It is deliberately quick: enter an amount, choose the rate, choose add or remove, and the result gives net, VAT and gross figures.

It does not tell you whether your goods or services should be standard-rated, reduced-rated, zero-rated, exempt or outside the scope of VAT. That classification matters, so use GOV.UK rate guidance or advice when the rate is not obvious.

TaskFormula at 20%
Add VATNet x 1.20
Remove VATGross / 1.20
VAT inside grossGross x 1/6
Gross from VAT onlyVAT x 6

How this VAT calculator works

Inputs used

  • Calculation direction: add VAT, remove VAT, or show only the VAT element in a gross price.
  • Amount entered by the user, treated as net for add-VAT mode and gross for remove-VAT modes.
  • VAT rate: 20%, 5%, 0%, or a custom percentage.
  • Quantity or repeated invoice-line count.
  • Rounding mode: round the invoice total or round each line first.

Calculation method

  • For add-VAT mode, multiply the net amount by the VAT rate to get VAT, then add it to the net amount.
  • For remove-VAT mode, divide the gross amount by 1 plus the VAT rate to get the net amount, then subtract net from gross.
  • For VAT-only mode, use the same gross-price calculation but emphasise the VAT element.
  • For quantity, calculate either one total amount or repeated line amounts depending on the rounding option selected.
  • Round money results to two decimal places for display, and show a line-versus-invoice rounding warning where the two methods differ.

Assumptions

  • The selected rate is assumed to be correct for the supply. Check GOV.UK VAT rate guidance if you are unsure.
  • The calculator treats zero-rated VAT as a 0% taxable rate. It does not treat exempt or outside-scope supplies as reclaimable input tax.
  • The rounding comparison is an invoice-check estimate. Your accounting software may use a consistent HMRC-acceptable method that produces small penny differences.

What this does not cover

Worked examples

If you quote GBP 100 plus VAT at the standard 20% rate, the VAT is GBP 20 and the customer pays GBP 120. That is the easy direction: net price multiplied by 1.20.

If a receipt says GBP 120 including VAT at 20%, the net price is GBP 100. You get there by dividing GBP 120 by 1.20. The VAT element is GBP 20, which is one sixth of GBP 120.

At the reduced 5% rate, a GBP 105 gross bill has GBP 100 net and GBP 5 VAT. The VAT fraction is 5/105, which reduces to 1/21. That is why the calculator divides by 1.05 rather than taking 5% off the gross price.

Rounding check for invoices

Invoice rounding is the small-but-annoying bit of VAT. If a line item creates fractions of a penny, one system may round each line first while another rounds the invoice total. Both can be reasonable if used consistently and within HMRC guidance, but they can differ by a penny or two.

This calculator lets you compare the two approaches for repeated items. It is useful when a supplier invoice does not quite match the figure in your spreadsheet. For a formal VAT return, your bookkeeping records and accounting method still matter more than a quick calculator check.

If you run a retail business, be extra careful. HMRC has separate guidance for retailers, and many retailers account for VAT through a retail scheme rather than by ordinary invoice-line calculations.

Zero-rated, exempt and outside scope are not the same

Zero-rated

VAT is charged at 0%. The supply is still taxable, which can matter for VAT registration and input tax.

Exempt

No VAT is charged, but it is not the same as a 0% taxable supply. Input tax recovery may be restricted.

Outside scope

The transaction sits outside UK VAT altogether. It should not be treated as simply another VAT rate.

This distinction sounds fiddly, but it matters in real bookkeeping. A zero-rated book sale, an exempt insurance transaction and an outside-scope disbursement can all show no VAT on the customer-facing price, yet they can be treated differently for VAT records. When the classification is uncertain, the official rate guidance is the better source than any simple VAT calculator.

Common VAT mistakes this helps catch

Taking 20% off a VAT-inclusive price

For 20% VAT, divide by 1.20 or multiply the gross price by one sixth to find the VAT element.

Using 0% when the supply is exempt

Zero-rated and exempt can both show no VAT charged, but they are not the same for VAT accounting.

Mixing invoice and line rounding

Small penny differences often come from rounding each line first instead of rounding the invoice total.

Assuming every business cost has recoverable VAT

You normally need a proper VAT invoice and the purchase must be recoverable under the VAT rules.

VAT calculator FAQs

How do I add 20% VAT?
Multiply the net price by 1.20. For example, GBP 100 plus 20% VAT becomes GBP 120, made up of GBP 100 net and GBP 20 VAT.
How do I remove VAT from a price?
Divide the VAT-inclusive price by 1 plus the VAT rate. At 20%, divide by 1.20. At 5%, divide by 1.05.
Is 0% VAT the same as exempt?
No. Zero-rated supplies are taxable at 0%. Exempt supplies are outside taxable VAT for different purposes, and input tax recovery can be restricted.
Why does my invoice differ by a penny?
Usually because one system rounded VAT on each line while another rounded the invoice total. The calculator shows both approaches so you can spot this quickly.
Can I use this for a VAT return?
Use it as a check, not as your VAT return system. VAT returns depend on your full records, input tax, output tax, schemes, adjustments and accounting period.

Official sources

Last verified: June 6 2026. Calculations are estimates based on the published rules and assumptions shown on this page.

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