What to include on an invoice: the complete checklist
An incomplete invoice is the most common reason freelancers get paid late: the client's accounting team bounces it back, and the payment clock restarts. Here is what a professional invoice needs, top to bottom.
1. The word "Invoice" and a number
State clearly that the document is an invoice, and give it a unique, sequential number (e.g. INV-2026-001, INV-2026-002…). Sequential numbering isn't just tidy — in most countries tax authorities expect an unbroken series, and gaps raise questions in an audit. Keep quotes in a separate series.
2. Your details and your client's
- Your name or business name, address, and any registration number (company number, VAT/tax ID) your jurisdiction requires;
- Your client's name or business name and address — and their VAT number for cross-border B2B invoices in Europe.
Invoice the exact legal entity that ordered the work. "Acme" and "Acme Holdings Ltd" may be different companies, and the wrong name can void the invoice.
3. Dates
The issue date and the due date. Prefer an explicit date ("Due 15 August 2026") over "net 30" — it removes any ambiguity about when late-payment terms kick in. If the work was delivered on a different date, mention it.
4. Line items
For each line: a precise description, the quantity, the unit (hours, days, units) and the unit price. Vague descriptions ("consulting services") invite disputes; specific ones ("Payment module development — 3 days") get approved faster. Show any discount explicitly rather than silently lowering a price.
5. Tax treatment
If you charge VAT or sales tax: show the rate and amount per rate, plus the total including tax. If you don't, say why in a footer note — small-business exemption, reverse charge for EU B2B services, or supply outside the scope of the tax. An invoice that is silent about tax looks unfinished to any accountant.
6. Payment details and terms
- How to pay: bank account (IBAN/BIC or account number and sort/routing code) or other accepted method;
- Payment terms: due date, any late-payment interest, and any early-payment discount;
- A payment reference — usually the invoice number — so you can match the incoming transfer.
Pre-send checklist
| Check | Why |
|---|---|
| Number continues your series | No duplicates, no gaps |
| Client legal name is exact | Wrong entity = invalid invoice |
| Totals add up, tax shown or explained | The first thing accounting verifies |
| Due date is explicit | Starts the late-payment clock |
| Bank details are current | Misdirected payments take weeks to recover |
The easy way
The free Facturio invoice generator structures all of this for you — sequential numbering suggestions, per-rate VAT breakdowns, payment block, EUR/USD/GBP — and generates the PDF inside your browser, so your client data never touches a server.