How to write an invoice
An invoice is not a polite request for money. In most countries it is a document with legally required content, and a missing line is exactly what lets a client put off paying it.
Every invoice needs both parties' details, a unique number, the date, a clear description of what was sold, the amount before tax, the tax, the total, and the payment terms. Fill the template, download the PDF, send it.
Fill in the free templateStep by step
- Identify both sides
Your name or company, your address and your registration or tax number; then the client's name and address.
- Number it and date it
One number per invoice, never reused, in a sequence with no gaps. Add the issue date and the date payment is due.
- Describe what you are charging for
One line per item, with the quantity and the unit price. A vague description is the most common reason an invoice comes back with questions.
- Total it and say how to pay
Amount before tax, tax rate and amount, total to pay — then your bank details and the deadline.
Numbering invoices
The rule is much the same everywhere: a continuous sequence, with no gaps and no duplicates. A year prefix keeps it readable — 2026-001, 2026-002 — and makes the year obvious at a glance.
Never delete an invoice you have already sent. Issue a credit note instead, so the sequence stays intact and the correction is visible.
Tax: the line that varies most
The rate, and whether you charge tax at all, depend on where you are, what you sell and who you sell it to. Small businesses under a threshold are often exempt and have to say so on the invoice.
Sales to a business in another country frequently move the tax to the buyer. This is the part to check locally rather than copy from any template, including this one.
Payment terms, and what to do when nothing arrives
State the deadline as a date, not as 'on receipt': a date can be enforced, a phrase can be argued about. Thirty days is the usual default between businesses, and many countries cap how long a deadline may be.
If the date passes, a polite reminder is the first step and a formal notice is the second. Both are ordinary business, and both work better in writing.
Frequently asked questions
Do invoice numbers have to run in order?
In most countries, yes: the sequence must be unbroken so that no invoice can quietly disappear. Gaps are the first thing an audit looks for.
Can I invoice without a company?
It depends where you are. Selling regularly usually requires a registered status of some kind, while an occasional sale between individuals calls for a different document — a bill of sale rather than an invoice.
How long do I have to keep my invoices?
Several years in most jurisdictions, often between five and ten, and the same goes for the invoices you receive. Keep the PDFs, because they are the record.