What is a tax invoice?
A tax invoice is the document a GST-registered supplier must issue for every taxable supply of goods or services, as required under Section 31 of the CGST Act, 2017 and detailed under Rule 46 of the CGST Rules, 2017. It is the primary evidence a recipient needs to claim input tax credit on that purchase.
Mandatory fields on a tax invoice
- Supplier's name, address and GSTIN; a consecutive invoice serial number; date of issue.
- Recipient's name, address and GSTIN (where registered), and shipping address for B2B supplies.
- HSN/SAC code, description, quantity, unit and total value of goods/services.
- Taxable value, applicable GST rate, and the amount of CGST, SGST/UTGST or IGST charged.
- Place of supply (for inter-state supplies), and signature or digital signature of the supplier or authorised representative.
When it must be issued
- For a supply of goods, generally before or at the time of removal/delivery of the goods.
- For a supply of services, generally within the prescribed time limit from the date of supply, as specified under the CGST Rules.
- If the recipient is registered and the turnover crosses the e-invoicing threshold, the invoice must also carry a valid IRN and QR code per the e-invoicing rules.
Common mistakes
- Missing mandatory fields such as HSN code or place of supply, which can jeopardise the recipient's input tax credit claim.
- Not maintaining a consecutive invoice numbering sequence as required under the rules.
- Issuing a simple bill instead of a proper tax invoice for a B2B taxable supply.
Sources
Last updated 2026-10-12.
