VAT Calculator · Practical guide
How to Add VAT to an Invoice
Multiply the net amount by 1 + rate, and show the net, VAT, and gross as separate invoice lines.
At a glance
The Short Answer
To add VAT to an invoice, multiply the net amount by 1 + rate. At 20%, multiply by 1.20: a €250.00 service charge becomes a €300.00 invoice total — €250.00 net plus €50.00 VAT. Enter your amount and rate in the calculator above, set Add VAT, and you get all three figures.
Interactive tool
VAT Calculator
Enter your own values, then compare the result with the examples below.
VAT Breakdown
The Formula
VAT amount = net × rate and gross = net × (1 + rate), with the rate as a decimal. Both lines matter on an invoice: the net is your revenue, the VAT is tax you collect on behalf of the authority, and the gross is what the client pays.
Worked Invoice Examples
| Net Amount | VAT Rate | VAT | Invoice Total |
|---|---|---|---|
| 100.00 | 20% | 20.00 | 120.00 |
| 250.00 | 20% | 50.00 | 300.00 |
| 1,000.00 | 19% | 190.00 | 1,190.00 |
| 1,000.00 | 21% | 210.00 | 1,210.00 |
| 5,000.00 | 25% | 1,250.00 | 6,250.00 |
Invoicing Basics for VAT-Registered Businesses
Show the net, the rate applied, the VAT amount, and the gross as separate lines, along with your VAT registration number — most tax authorities require valid VAT invoices for your customers to reclaim the tax. Remember the VAT you collect is not income: each filing period you subtract the input VAT you paid on purchases and remit only the difference.
Watch Out for Mixed Rates
If an invoice covers items at different rates — say standard-rate services plus a reduced-rate item — calculate VAT per line at its own rate rather than applying one rate to the whole total.
Frequently Asked Questions
How do I add 20% VAT to a price?
Multiply the net price by 1.20. A 100.00 net price becomes 120.00 gross, which includes 20.00 of VAT.
What must a VAT invoice include?
Typically the net amount, VAT rate, VAT amount, gross total, your VAT number, and an invoice date and number. Exact requirements vary by country.
Is the VAT I charge customers my income?
No. Output VAT is collected on behalf of the tax authority. You remit it each filing period, minus the input VAT you paid on business purchases.
When should I not charge VAT on an invoice?
Common cases include sales to customers outside the VAT territory, zero-rated goods, exempt supplies, or being below the registration threshold. Check your local rules.