GST invoice format for service providers, not product sellers

Most invoice templates are built with a product business in mind — quantity, unit price, shipping address. A service invoice needs a different shape, and copying a goods template leads to fields that do not apply and fields that are missing.

Use SAC codes, not HSN

Services are classified under the Services Accounting Code system, not HSN, which is for goods. Consulting, design, development, and most freelance work fall under SAC codes specific to the service category — using an HSN code here is a mismatch that can flag the invoice during review.

Describe the work, not a quantity

• A clear description of the service performed, not a generic line item
• The billing period or milestone the amount corresponds to
• Hours or a fixed fee, whichever the engagement was agreed on
• No shipping address or delivery terms — these do not apply to services

Keep the tax treatment consistent with the client state

The CGST, SGST, or IGST split still applies exactly as it does for goods, based on where the client is registered. The service-specific parts are the classification code and the line item description — the tax mechanics underneath stay the same.

Paxbil generates correctly formatted service invoices with SAC codes built in — see Paxbil for freelancers