Guides

What has to be on an invoice (and the three omissions that delay payment)

The elements that make an invoice a valid business document almost everywhere, plus what actually keeps you waiting for the money.

Countries differ on tax wording and almost nowhere differs on the rest. Get the list below right and your invoice will be accepted by a finance department in Berlin, Seoul or Chicago — and, more to the point, it will not sit in someone’s inbox for two weeks while they work out who sent it.

The elements

These appear in essentially every national requirement list. Miss one and you are relying on goodwill.

• The word “Invoice”, so it is not filed as a quote. A document that does not say what it is gets treated as correspondence.
• A unique invoice number that never repeats and never goes backwards.
• The issue date, and separately the due date. “Net 30” alone makes the reader do arithmetic, and that delays it.
• Your full legal name or company name, address, and tax registration number where you have one.
• The client’s legal name and address. Their trading name is often not the entity that pays.
• A description of what you supplied, itemised, with quantity and unit price.
• The tax treatment: rate, amount, and any exemption wording that applies.
• The total due and the currency, written so it cannot be misread — “1,250.00 EUR” rather than a bare number.
• How to pay you: bank name, account, IBAN or routing number, SWIFT/BIC for international transfers.

The three omissions that cost you time

No purchase order or reference number. Larger clients pay from a PO. An invoice without the reference they gave you drops into a queue for manual matching, and that queue is measured in weeks.

No named contact. “Attn: Accounts Payable” is a wish. A person’s name is a route.

No due date on the document itself. Terms buried in a contract are invisible to the person clicking approve.

Before you send

• Does it say “Invoice” at the top?
• Is the number unique, and the next one in sequence?
• Is the client’s legal entity name correct — not their brand name?
• Is a due date printed, as a date?
• Are your bank details complete enough for an international transfer?
• If tax is zero, does the document say why?

Worth knowing

• This is a general checklist, not a statement of the law where you or your client are established. National rules add requirements — see the country guides in this section.