UK VAT Calculator
Use this quick tool to add VAT to a net amount or remove VAT from a gross amount.
What is UK VAT?
VAT (Value Added Tax) is a consumption tax charged on most goods and services in the UK. Businesses that are VAT-registered collect VAT from customers and then pay it to HMRC, usually after offsetting any VAT they have paid on business purchases.
If you are a business owner, freelancer, eCommerce seller, contractor, or simply checking invoices, understanding how to calculate VAT correctly is essential for accurate pricing, bookkeeping, and tax compliance.
Current UK VAT rates (quick overview)
- 20% (Standard rate): Most goods and services.
- 5% (Reduced rate): Some qualifying goods/services such as certain home energy supplies and some safety products.
- 0% (Zero rate): Items like most basic food and children’s clothing (with specific rules).
Note: Zero-rated is not always the same as exempt. Exempt supplies often have different input VAT recovery rules. Always confirm with the latest HMRC guidance for your industry.
How to calculate UK VAT
1) Add VAT to a net amount
If your price is before VAT (net), use:
VAT amount = Net × (VAT rate ÷ 100)
Gross amount = Net + VAT amount
Example: Net £100 at 20% VAT
- VAT = £100 × 0.20 = £20
- Gross = £100 + £20 = £120
2) Remove VAT from a gross amount
If your total includes VAT (gross), use:
Net amount = Gross ÷ (1 + VAT rate ÷ 100)
VAT amount = Gross − Net
Example: Gross £120 at 20% VAT
- Net = £120 ÷ 1.20 = £100
- VAT = £120 − £100 = £20
When these calculations matter most
- Creating customer invoices with clear net, VAT, and gross totals
- Setting retail prices while protecting your margin
- Checking supplier invoices for mistakes
- Preparing VAT returns and reconciliations
- Comparing quoted prices that may or may not include VAT
Common mistakes to avoid
Confusing gross and net values
A frequent issue is applying VAT to a price that already includes VAT, which overstates tax and final price.
Using the wrong rate
Not every sale is 20%. Depending on your goods/services, the reduced rate, zero rate, or exemption rules may apply.
Rounding inconsistently
Rounding each line item versus rounding totals can produce small differences. Use a consistent method in your accounting process.
Assuming all customers pay VAT
Some clients (especially consumers) see VAT as part of the final price, while B2B customers may focus on net price. Be clear in quotes and invoices.
Tips for better VAT accuracy
- Label amounts clearly as Net, VAT, and Gross.
- Keep evidence of applicable VAT rates for your products/services.
- Review edge cases: discounts, returns, shipping, mixed-rate baskets, and international sales.
- Use accounting software for records, but understand the formulas manually for quality checks.
Final note
This page gives practical guidance for calculating UK VAT quickly. Tax treatment can vary by sector and transaction type, so for high-value or complex cases, consult an accountant or HMRC resources to confirm the correct VAT treatment.