What to put on an invoice: a checklist for small businesses

Sometimes a late payment has nothing to do with the client's cash. It starts with an invoice that can't be processed: a missing tax number, a vague due date, a total nobody can trace back to the agreed work. Before you think about reminders, make sure the invoice itself answers every question an accounts team might ask.

1) Who it's from. Your business name and, if it differs, your registered legal name, plus your address, email and phone number. If you're registered for tax, add your tax number; some accounts teams won't book an invoice without it.

2) Who it's for. The client's registered company name, not just the person you work with day to day. Add their address and tax number when they have one. An invoice addressed only to an individual employee can bounce back from a finance department.

3) A unique invoice number. Every invoice gets its own number, and the numbers follow one consistent sequence. It's how you, your client and your accountant refer to the same document. Don't reuse a number, even after cancelling an invoice.

4) Issue date and due date. Write both as real calendar dates. "Net 30" is fine as a payment term, but a printed due date removes any doubt about when the clock started and when it stops.

5) Line items that match the agreement. One line per service or product, each with a clear description, quantity, unit price and line total. "Design work" invites questions; "Homepage redesign, three revision rounds, as quoted on 4 May" doesn't. If you agreed a discount, show it rather than quietly lowering the price, so the client can see it was honoured.

6) Tax, shown separately. Show the tax rate on each line, then the subtotal, the tax total and the grand total. Which tax applies, at what rate, and whether you need to charge it at all depends on where you and your client are based. Check your local rules or ask an accountant; no general checklist can answer that for you.

7) Currency. If you work with clients abroad, state the currency on the invoice itself, not only in the email. If you convert amounts for your own records, note the exchange rate you used.

8) Payment terms and how to pay. Say how many days the client has, which payment methods you accept, and what happens if payment is late, for example a late fee your contract allows. Put it on the invoice, not only in an email thread from three months ago.

9) A short note. A one-line thank-you, or a project or purchase-order reference, costs nothing and makes the invoice easier to match to the right work.

How QuickBill fills this in. You enter your business details once in the organization settings (name, legal name, address, contact details, tax number and logo), and they appear on every invoice and quote PDF. Clients are saved with their own address and tax number. Each invoice is numbered automatically, with a prefix you can set, and you choose the issue date, due date and currency for each document.

Line items take a description, quantity, unit price, discount and tax rate, and QuickBill calculates the subtotal, discount, tax and total for you. Notes and terms & conditions have their own fields, and you can set default payment terms and default terms text so every new invoice starts with them filled in.

When you send an invoice by email, your client receives the PDF and a link to view it online, and you can see when it was opened. If a client pays in parts, you record each payment and the invoice shows what is still due.

What this checklist doesn't cover. Some countries require extra fields, specific wording, or an electronic invoice format for certain clients. Which of these apply to you is a question for your local rules or your accountant. Get the basics above right first; they answer most of the questions a client's accounts team will ask.