What to put on an invoice

An invoice does two jobs and they pull in different directions. It is a record, which wants completeness, and it is a request for money, which wants to be easy to act on. A document that is only a record gets filed. A document that is only a request gets queried. Almost every field below exists to serve one job or the other, and it is worth knowing which.

The four that decide whether you get paid

Who is being billed, exactly. Not the person who briefed you — the entity that holds the budget. In a company of any size these are different, and an invoice addressed to your contact rather than to the company is an invoice that has to be reissued before it can enter the system. Ask for the billing name, the billing address and, if there is one, the accounts payable email. That last one is the single most useful thing you can collect before starting work.

A due date, written as a date. "Net 30" is a term, not a date. Somebody has to convert it, and the person converting it is either you or a stranger in a payables queue who has no reason to round in your favour. Print the actual day. Keep the term beside it if you like — Net 30 — due 22 October 2026 — but the date is the part that gets diarised.

How to pay, in full. Bank name, account number, sort code or routing number, IBAN and SWIFT if the payment crosses a border. An invoice that says "bank transfer" without the details is an invoice that generates an email, and that email will not be answered on the day it is sent. If you take card or a payment link, put that beside the bank details rather than instead of them: the two suit different payers, and the fees are different too — the payment fee calculator is where to find out what each one actually leaves you.

What the work was, in their words. "Consulting — September" is a line that has to be explained to whoever approves it. "Rebuild of the checkout flow, as agreed 2 Sept" approves itself. The description is not for you; you know what you did. It is for a person two desks away from your contact who has to decide whether this is a real commitment.

The ones that matter to the file, not the payment

Your own trading name and address, your tax registration number if you have one, the invoice date, and a unique invoice number. None of these will make a payment arrive faster. All of them will be asked for eventually — by your accountant, by their auditor, or by you in eighteen months when you are trying to work out what happened.

The invoice number is the one worth thinking about rather than generating at random. It is the handle everybody uses to refer to this document for the rest of its life. Invoice numbering covers what makes a scheme survive contact with a second client and an accountant.

Tax, and the one thing to get right

Whether you charge tax, at what rate, and what you must show on the document are all local questions, and this page will not answer them — the rules differ by country, by what you sell and by whether your customer is a business or a consumer. Ask an accountant once and you are set for years.

For a sense of what a tax authority actually asks for, the UK is a useful example because HMRC publishes the list. VAT Notice 700, section 16.3.1, says a VAT invoice must show, among other things: a sequential number that uniquely identifies it, the time of supply and the date of issue, your name, address and VAT registration number, the customer's name and address, a description of what was supplied, the quantity or extent of it with the VAT rate and the amount excluding VAT, and the total VAT — in sterling even when the invoice is in another currency. That is one country's rule for one tax; other countries publish their own lists, and yours is the one to check.

The thing that is universal is stating whether your prices include tax or sit underneath it. A line reading "£1,000" with "VAT 20%" beneath it can mean £1,000 or £1,200 depending on a convention the reader cannot see, and that ambiguity is resolved in the payer's favour roughly as often as you would expect. Say which it is on the document. If you need to work backwards from a tax-inclusive figure, that is a division rather than a subtraction, and the VAT calculator does it.

What to leave off

Your hourly rate, when you are billing a fixed price. Your costs. Your margin. A breakdown so granular that it invites line-by-line negotiation after the work is finished. An invoice is the wrong place to reopen the commercial conversation, and detail you did not need to supply is detail somebody can dispute.

Late payment terms are the exception people get backwards. A line saying what happens if the invoice goes unpaid belongs on the document, but it belongs there because you agreed it before the work started — not because you added it to this invoice after the last one was late. A charge that first appears on the invoice is a charge with nothing behind it.