GST invoice format: what every bill must show

The GST invoice format in short

A GST tax invoice must show the details listed in Rule 46 of the CGST Rules: your name, address and GSTIN, a unique invoice number, the date, the buyer's details, HSN code, description, quantity, taxable value, tax rate and tax amount, place of supply for inter-state sales, and a signature. There is no single government template; any layout works as long as these fields are on it.

The rules below are as of October 2026. They come from the CGST Act and Rules, which CBIC publishes on its tax information portal. Where a rule depends on your business, check with your CA.

Mandatory fields under Rule 46

Rule 46 lists the particulars in clauses (a) to (s). For a normal shop or distributor, these are the ones that matter.

Exports and supplies to SEZ units need an extra endorsement and the country of destination. Most retail shops will not deal with these.

B2B and B2C invoices: what changes

A B2B invoice goes to a buyer with a GSTIN. A B2C invoice goes to a consumer or anyone without a GSTIN. The core fields are the same. The buyer section is where they differ.

B2B invoices

• The buyer's name, address and GSTIN are compulsory on every bill, whatever the value.
• The buyer claims input tax credit on the basis of your invoice and your GSTR-1. A wrong GSTIN means they lose credit until you correct it.
• If you are under e-invoicing, every B2B invoice needs an IRN before it is valid.

B2C invoices and the ₹50,000 rule

• When the taxable value is ₹50,000 or more, Rule 46 asks for the buyer's name and address, the delivery address, and the state name and code, even though the buyer has no GSTIN.
• Below ₹50,000, you record these details only if the buyer asks for them.
• For walk-in sales of less than ₹200, section 31(3)(b) lets you skip a separate invoice when the buyer is unregistered and does not want one. You must then issue one consolidated invoice for such sales at the end of the day.

Example: a supermarket in Kochi sells a fridge for ₹62,000 to a walk-in customer. The bill must carry the customer's name, address and state. A ₹1,800 grocery bill to the same customer does not need them.

Invoice numbering rules

Numbering trips up many shops at the start of April. Keep these points in mind.

• Up to 16 characters. Count everything, including prefixes and slashes. "KM/2627/000154" is 14 characters and fine.
• Unique in the financial year. Most shops start a fresh series on 1 April with the year in the prefix, such as 2627 for 2026-27.
• Consecutive. Do not skip numbers. If you cancel a bill, keep its number marked as cancelled. You report the range used and the number cancelled in Table 13 of GSTR-1.
• More than one series is allowed. You can run separate series for each counter, branch or document type, for example "A" for counter 1 and "B" for counter 2. Each series must stay unique and consecutive.
• Credit notes, debit notes and delivery challans should have their own series.

Signature and copies

Rule 46 asks for the signature or digital signature of the supplier or an authorised representative. A printed name with "Authorised Signatory" and a signature is the usual way on paper. An electronic invoice issued under the Information Technology Act, 2000 does not need the signature.

Rule 48 sets the number of copies:

For counter sales the customer takes the bill with the goods, so in practice one print plus your saved copy is how most shops work. For goods sent by vehicle, print the transporter's copy as well, and see our guide to e-way bill rules.

Sample GST invoice layout

This is a simple layout for an intra-state B2B sale by a grocery wholesaler. The shop names and numbers are made up.

For an inter-state sale, replace CGST and SGST with IGST at the full rate and show the buyer's state as the place of supply. Rates shown here are examples; check the current rate for each item before you bill.

Tax invoice or bill of supply

A tax invoice is issued for taxable supplies by a regular GST-registered person. A bill of supply (Rule 49) is issued when no tax is charged on the bill: by a dealer under the composition scheme, or for exempt goods such as fresh vegetables. A bill of supply does not show tax, because no tax is collected.

• A composition dealer cannot charge GST or issue a tax invoice. Their bills say "composition taxable person, not eligible to collect tax on supplies".
• A regular dealer who sells both taxable and exempt goods to an unregistered buyer can issue a single "invoice-cum-bill of supply" (Rule 46A).

Which document you need depends on your registration type and what you sell. If you are unsure, check with your CA.

Revised invoices, credit notes and debit notes

You cannot edit a GST invoice after it is reported. Corrections go through separate documents.

• Revised invoice (Rule 53): for a new registration, you can issue revised invoices for supplies made between the effective date of registration and the date the certificate was issued, within one month of the certificate.
• Credit note (section 34): for returns, a lower price after billing, or excess tax charged. It must refer to the original invoice. A credit note for a supply must be declared by 30 November after the end of that financial year, or by the date you file the annual return, whichever is earlier.
• Debit note: when the value or tax on the original bill was too low.

Credit and debit notes are reported in GSTR-1. See our guide to GSTR-1 for retailers.

Common mistakes on GST invoices

• Invoice numbers longer than 16 characters, or the same number used twice in a year.
• CGST and SGST charged on an inter-state sale, or IGST on a local sale.
• No buyer details on a B2C bill of ₹50,000 or more.
• HSN with fewer digits than your turnover requires.
• Rounding each line differently from the total, so the bill and the return do not match.
• Editing an old bill instead of issuing a credit note.

Doing this in Cartix Prime

Cartix Prime prints bills on 58 mm and 80 mm thermal printers and as A4 invoices. A4 invoices carry the HSN summary, amount in words, bank details and terms, with up to 3 copies. You can show GST by rate and each line's amount before tax, GST % and after tax. GST reports are on every plan. Cartix Prime does not have a composition-scheme bill of supply mode. See GST billing software for details.