What to include on an invoice: a complete checklist

An invoice does two jobs: it asks your customer to pay, and it becomes a record for both of you, and often for the tax authorities. A clear invoice gets paid faster and causes fewer questions. Below is the information most professional invoices include. Exact legal requirements differ from country to country, so check with an accountant or your tax authority for the rules that apply to you.

1. The word "Invoice" and a unique number

Label the document clearly as an invoice (or "Tax invoice" where your tax system requires that wording). Give every invoice a unique number that follows a sequence, such as INV-0001, INV-0002. Never reuse a number, even if an invoice is cancelled; issue a credit note instead.

2. Dates

• Issue date: the day you create the invoice.
• Due date: when payment must arrive. Writing an actual date ("Due 30 November") is clearer than terms alone ("Net 30").
• Supply date (if different): when the goods were delivered or the work was done. Some tax systems require this.

3. Your business details

Your legal business name (and trading name if different), full address, phone and email. If you are registered for VAT, GST or sales tax, include your tax registration number. Limited companies often need to show their company registration number too.

4. Your customer's details

The customer's name or legal business name and billing address. For business customers, add a contact person and, where relevant, their tax number. If goods go to a different address, show the delivery address separately.

5. A clear list of what you are charging for

Each line should say what was supplied, how much, and at what price: description, quantity, unit (hours, days, pieces, boxes), unit price and line total. For products, include SKUs or product codes. Vague lines like "Services" invite questions and slow payment.

6. Discounts, tax and totals

Show the subtotal, any discounts, delivery charges, the tax rate and tax amount for each rate you charged, and the grand total. If prices include tax, say so. If you charge no tax, a short note explaining why helps your customer and your accountant; ask your accountant for the correct wording.

7. Payment terms and how to pay

State when payment is due and how to pay: bank details, a payment reference to quote, or accepted payment methods. If you took a deposit or the customer paid part of the amount, show the amount paid and the balance still due.

8. References and notes

Customers often need your invoice to match their records. Include their purchase order number, your quotation number or a delivery note reference. A short thank-you note doesn't hurt either.

Quick checklist

• Title "Invoice" and unique sequential number
• Issue date and due date
• Your name, address and tax/company numbers
• Customer's name and address
• Itemised lines: description, quantity, unit price, total
• Subtotal, discounts, tax by rate, grand total
• Payment terms, bank details and payment reference
• Purchase order or quotation reference, if any