What to Put on an Invoice: The Complete Checklist

A complete invoice needs your details, the client's details, a unique invoice number, the issue date and due date, clear line items with descriptions and prices, the subtotal, any tax, the total, and your payment details. Miss one of these and you hand the client a reason to delay while they come back to ask.

Think of an invoice as a document that has to be paid by someone who has never spoken to you. The client's finance team should be able to process it cold, with no need to email you for the missing piece. Everything below exists to make that possible.

Whose details go on an invoice?

Two parties appear on every invoice: you and the client. Lead with your full name or business name, address, email, phone, and your tax registration number if you have one. Then add the client's company name, the person or department you are billing, their billing address, and any purchase order number they gave you.

Your tax or VAT registration number belongs in your own section if you are registered. If you are not registered, you leave it out.

If the client gave you a purchase order number or an internal reference, include it, because large organisations often will not process an invoice that is missing their PO reference. Sending the invoice to the right person also matters more than it sounds, since the person who commissioned the work is frequently not the person who pays it.

What invoice number and dates does an invoice need?

Every invoice needs one unique invoice number in a sequential series, such as INV-001 or 2026-001, so both sides can reference it and your records stay in order. It also needs two dates: the issue date, which your payment terms count from, and the due date, shown as a real calendar date rather than only a term.

The full approach to numbering is in how to number your invoices, and the rule is simply: unique, sequential, never skipped or reused.

Spell the due date out so nothing is left to interpret: "Due 1 July 2026 (Net 30)". How to set and phrase terms is in how to write clear payment terms on an invoice.

How should you list line items on an invoice?

Line items are the core of the invoice. Give each thing you charge for its own row with a description, a quantity, a unit price, and a line total. Keep the descriptions specific, since a clear line clears faster than a vague one. Separate different categories of work into distinct lines rather than lumping them together.

Be specific in the descriptions. "Copywriting, 3,000 words at 0.12 per word, 360" tells the reader precisely what they are paying for. "Writing work, 360" invites a query. The more clearly each line states what was delivered, the faster the invoice clears, because the person approving it can see the value without asking you to explain it.

How do you show totals and tax on an invoice?

Below the line items, lay the money out in order: the subtotal first (every line total added up before tax), then any tax such as VAT or GST on its own line showing the rate and amount, then the final total the client pays. State the currency explicitly so 1,000 is never ambiguous.

If you are tax registered, the tax must appear as a separate line so the client can reclaim it, and your registration number must be on the invoice. If you are not registered, there is no tax line. The mechanics of adding tax are in how to add VAT to an invoice.

Where do payment details go on an invoice?

Put your payment details clearly at the bottom of the invoice. List every method you accept with the exact information each one needs: account name, number and sort code for a domestic transfer, IBAN and BIC for international, or a payment-link address. If the reader cannot work out how to pay without contacting you, you have built in a delay.

An invoice that does not say how to pay it is an invoice that gets paid late. Give the client every route they might use, so they can send the money the moment the invoice is approved.

What is the quick pre-send invoice checklist?

Before you send, confirm each item is present: your details and tax number if registered; the client's details and any PO reference; a unique invoice number; the issue date and a calendar due date; specific line items with quantities and prices; the subtotal, any tax line, and the total; your payment details; and your terms.

If every item is present, the invoice is complete and ready to be paid without a follow-up. The full walk-through of building one from scratch is in how to create an invoice.

The simplest way to make sure nothing is missing is to use a tool that prompts for each field. The free invoice generator produces a clean, numbered invoice with all of these elements in place, running in your browser with no signup and nothing stored on a server. Fill it in once, and the structure carries to every invoice after.

Common questions

What are the essential things every invoice must have?

Your details and tax number if registered, the client's details and any purchase order reference, a unique invoice number, the issue date and a calendar due date, clear line items with descriptions, quantities, and prices, the subtotal, any tax line, the total, and your payment details. If every one of these is present, the invoice can be processed by someone who has never spoken to you, which is the whole goal. A missing field is a reason for the client to come back and ask, which delays payment.

Do I need a logo or a registered company to invoice?

No. An invoice needs the right information laid out clearly, not branding or a particular legal status. A sole trader can invoice under their own name, and a plain, well-structured document is every bit as valid as a designed one. Even so, a clean and consistent layout does signal that you take your business seriously, which can make clients more comfortable paying promptly. The content is what makes the invoice valid. The presentation is what makes it look professional.

How should I describe line items on an invoice?

Specifically enough that the person approving the invoice can see exactly what they received. "Copywriting, 3,000 words at 0.12 per word, 360" is clear. "Writing work, 360" invites a query. Give each distinct piece of work its own line rather than lumping everything together, and include a description, quantity, unit price, and line total for each. The clearer each line is, the faster the invoice clears, because the approver does not need to ask you to explain it.

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Related articles

• How to Create an Invoice: A Practical Guide
• How to Write Clear Payment Terms on an Invoice
• How to Number Your Invoices: A Simple System