An invoice is a request for payment that also serves as a record for both sides. A good one leaves no room for questions: who is billing whom, for what, how much, and by when. Here's how to write one properly.
1. Label it clearly
Put the word Invoice at the top, along with a unique invoice number. Sequential numbers (INV-01, INV-02) keep your records tidy and make gaps easy to spot. On a VAT invoice they're also required: article 226 of the EU VAT Directive and HMRC's VAT Notice 700/21 both ask for a sequential number that uniquely identifies the invoice.
2. Add your details and theirs
Include your business name, address and contact details, plus your tax or VAT number if you have one. Then add the client's name and billing address. Both parties' details matter, especially on a VAT invoice. For UK invoices, gov.uk lists what an invoice must include.
3. Set the dates
Show the issue date and a due date. A concrete date (“Due 30 April”) leaves less room for doubt than a term alone. If you use terms like Net 30, see what Net 30 means.
If you delivered the goods or finished the work on a different day, add that supply date too. Both the gov.uk list and the VAT Directive ask for it.
4. Itemise the work
List each product or service on its own line with a description, quantity and rate. Clear line items reduce disputes and make your invoice easy to approve.
5. Show the totals
Add a subtotal, any tax, and a clear grand total. If tax applies, show it as a separate line so the breakdown is obvious. On a VAT invoice, include the rate you applied as well as the amount of VAT.
6. Say how to pay
Include your bank details or IBAN and any reference you'd like quoted. A reference on the payment lets you match it to the right invoice when it arrives.
If you spot a mistake later
Once an invoice has gone out, the usual fix is a credit note that references it, then a corrected invoice, so your number sequence stays intact. You can make one with the credit note generator.
Let the tool do the fiddly parts
With Invoice Forever you pick your country and the currency, paper size and formatting follow (with tax rates pre-filled for 52 countries); the totals calculate themselves; and you download a clean PDF. It's free — you can make one right now.
