GST Invoice Template A GST invoice template should make the tax side of the invoice easy to understand while keeping the layout simple for the client. This page gives you a straightforward structure for service invoices that need a GST breakdown. Invoice fields - Invoice number: INV-2048 - Issue date and due date: May 18, 2026 / June 1, 2026 - Client and supplier details: Business names, email, address, and tax details - Payment terms: Net 14 - Payment method: Bank transfer details or payment link - GST calculation: Subtotal + GST amount + total Sample invoice Invoice number: INV-GST-42 Issue date: May 18, 2026 Due date: June 1, 2026 Bill from: Maple Lane Studio, billing@maplelane.example Bill to: Crown Point Co., ap@crownpoint.example Payment terms: Net 14 Line items - Monthly support retainer | 1 | $1,800.00 | $1,800.00 Subtotal: $1,800.00 GST (10%): $180.00 Total: $1,980.00 Notes: Monthly support invoice including GST.