What a GST tax invoice must contain
Under the GST invoice rules, a tax invoice generally needs the following details. Requirements can vary by case, so confirm them for your situation.
- Your name, address and GSTIN
- A unique invoice number, in one or more series, not more than 16 characters
- The date of issue
- Your customer's name, address and GSTIN if they are registered
- HSN code for goods or SAC code for services
- Description, quantity and unit of each item
- Total value and taxable value, after any discount
- Rate and amount of CGST, SGST/UTGST or IGST
- Place of supply, and the delivery address if different
- Whether tax is payable on reverse charge
- Your signature or digital signature
How to create one, step by step
- 1Add your business name, address, state and GSTIN.
- 2Add your customer's name, billing address, state and GSTIN if registered.
- 3Add each item with its description, HSN or SAC code, quantity and price.
- 4Set the GST rate for each item. GST rates and rules change, so always check the current rate for your goods or services on the official GST portal or with your tax professional.
- 5Decide the place of supply. If it is in your state, charge CGST and SGST; if it is in another state, charge IGST.
- 6Check the taxable value, tax and total, then give the invoice a unique number and date.
- 7Sign it, and issue a copy to your customer.
Worked example
A boutique in Maharashtra sells goods with a taxable value of ₹1,000 at a 5% GST rate to a customer in Maharashtra. The tax is ₹50, split into ₹25 CGST and ₹25 SGST, and the total is ₹1,050.
If the same sale were to a customer in Karnataka, the tax would be ₹50 IGST and the total would still be ₹1,050. The rate is the same; only the split changes.
Numbering invoices
Invoice numbers must be unique within a financial year. Many businesses include the year, for example INV-2026-27-0001, which keeps the number within 16 characters and makes the series easy to read.
Do it automatically
You can prepare invoices by hand, but a tool avoids arithmetic mistakes and picks CGST/SGST or IGST for you. Try our free GST invoice generator, or create a free Finex Business account to save customers, items and every invoice you issue.