How to write an invoice, step by step
The details a client needs to pay you without questions, in the order they usually appear, with a worked example at the end.
Step 1: Your details and the client's
Put your business name, address, and contact details at the top. Below that, add a "Bill to" block with the client's legal name and address. For companies, use the name their accounts team knows them by, and include a purchase order number if they gave you one; some businesses cannot pay without it.
Step 2: A reference number and dates
Give each bill a unique number in sequence (001, 002, 003…). Tax authorities in many countries, including VAT rules across the EU and UK, expect sequential numbering with no reuse. Add the issue date and a clear due date.
Step 3: Itemize the work
Use one line per product or service, with a description, quantity, unit price, and line total. "Services: $700" invites questions. "Website copywriting, 5 pages" does not.
Step 4: Totals and tax
Show the subtotal, any discount, the tax rate and amount, and the grand total. If you are registered for sales tax or VAT, include your registration number. If you are not, do not add tax.
Step 5: How to pay
Give the exact payment details: bank account and reference, a PayPal address, or a card payment link. Ask the client to quote the bill number with their payment, so you can match it.
Worked example
| Item | Qty | Rate | Total |
|---|---|---|---|
| Website copywriting (5 pages) | 5 | $120 | $600 |
| SEO meta descriptions | 1 | $80 | $80 |
| Total due by Oct 30 | $680 |
Sending it
Attach the PDF to a short email: "Hi Sam, attached is bill 014 for $680, due 30 October. Payment details are on the PDF. Thanks!" If it is not paid by the due date, send a polite reminder with the same number and amount.