GST invoice format: what every tax invoice in India must show

A tax invoice is more than a bill. Under GST it is the document your customer uses to claim input tax credit, and the one your returns are built from. Leave out a required detail and you risk a mismatch at filing time, or a customer who cannot claim their credit.

What a GST tax invoice must show

The CGST Rules (Rule 46) list what a tax invoice has to contain. In practice, every invoice should carry:

• Your details: name, address and GSTIN.
• An invoice number: consecutive, unique for the financial year, and no longer than 16 characters. Letters, numbers, hyphens and slashes are allowed.
• The date of issue.
• The customer's details: name, address and GSTIN if they are registered. For an unregistered customer, name and address are needed when the taxable value is ₹50,000 or more.
• HSN or SAC codes for the goods or services. Businesses with turnover up to ₹5 crore must show at least 4 digits on B2B invoices. Above ₹5 crore, 6 digits are required.
• Description, quantity and unit of each item.
• Taxable value after any discount.
• Rate and amount of tax: CGST and SGST (or UTGST), or IGST, plus cess where it applies.
• Place of supply with the state name, for inter-state supplies.
• Delivery address if it is different from the place of supply.
• Whether tax is payable on reverse charge.
• Your signature or digital signature, or that of an authorised person.

CGST and SGST, or IGST?

The tax you charge depends on where the supply happens compared with where you are registered:

A seller in Punjab billing a customer in Chandigarh, for example, charges IGST, because Chandigarh is a separate Union Territory. Getting this wrong is one of the most common invoice mistakes. The fix is a credit note and a fresh invoice.

How many copies?

For goods, the rules ask for three copies: the original for the recipient, the duplicate for the transporter and the triplicate for you. For services, two copies are enough. With digital invoices shared as PDFs, keeping these straight is much easier.

Mistakes that cause trouble later

1. Gaps or repeats in invoice numbers. Keep one series per financial year and never reuse a number.
2. The wrong place of supply, which leads to CGST + SGST being charged instead of IGST, or the other way round.
3. Missing HSN codes, or too few digits for your turnover.
4. A typo in the customer's GSTIN, which means they cannot see the invoice in their GSTR-2B.
5. Rounding differences between the line items and the total.

Let your billing software check this for you

Good billing software makes these mistakes hard to make. In Qora One GST every invoice numbers itself, the HSN and rate come from the product, and the CGST/SGST or IGST split follows the place of supply automatically. You can then print it in one of 10 templates with your logo, signature and UPI QR code, or share it on WhatsApp.

GST rules change from time to time. Treat this guide as a practical overview, and check current notifications or ask your tax adviser before relying on a specific threshold.