How to Write Invoice

Writing an invoice is a quick process when you use a clear template. The goal is a one-page document that tells the client exactly what they owe, why, and how to pay it.

To write an invoice: 1. Pick a free invoice template or generator like InvoiceSonic 2. Add your business name, ABN, and contact details at the top 3. Generate a unique sequential invoice number (INV-0001, INV-0002, …) 4. Add today's date 5. Enter the client's name and billing address 6. List each product or service with description, quantity, and rate 7. Calculate the line totals and the subtotal 8. Add GST if you're registered, and show it on its own line 9. Show the total amount payable 10. Set payment terms — Net 7, 14, or 30 days 11. Include bank, BPAY, or PayID details for payment 12. Save as PDF and email to the client

Always send invoices the same day work is completed and follow up before the due date. Keep a copy for at least five years to meet ATO record-keeping rules. InvoiceSonic does all the formatting and numbering for you.