GST reference · tax invoice

The GST bill format, field by field — with a worked example.

What Rule 46 requires on every GST tax invoice, when to charge CGST+SGST versus IGST, and a filled example you can copy the structure from. Or skip the manual work — TatvaBooks generates the correct format for you, every time.

Reviewed July 2026
6 min read
CA Anil Agarwal & the TatvaBooks team

What is a GST bill format?

A GST bill — properly called a tax invoice — is the document a GST-registered seller must issue for every taxable supply of goods or services. Its format isn't arbitrary: Rule 46 of the CGST Rules lays down a specific list of fields that must appear on it, from your GSTIN down to the amount in words. Get any of them wrong and the buyer's input tax credit — and your GSTR-1 — can be affected.

Below is the complete field list, followed by a filled example so you can see how it comes together.

Mandatory fields on a GST tax invoice

Every GST bill needs these six groups of information, in this order:

Seller (you)

Legal / trade name
Full address
GSTIN
State & state code

Buyer

Name and address
GSTIN (for B2B — mandatory if buyer is registered)
Place of supply (state name + code, especially for inter-state)

Invoice identity

Invoice number — consecutive, unique per FY, up to 16 characters
Invoice date

Line items

Description of goods/services
HSN (goods) or SAC (services) code
Quantity and unit (Nos, Kg, etc.)
Rate per unit
Discount, if any
Taxable value (after discount)

Tax breakup

CGST + SGST (intra-state) — rate and amount, split equally
IGST (inter-state) — rate and amount
Cess, if applicable

Totals & sign-off

Total invoice value
Amount in words
Reverse charge applicability (Yes/No)
Authorised signature (or digital signature)

CGST + SGST vs IGST — which one to charge

This is the field most small businesses get wrong. The rule is based on the buyer's place of supply, not on where the goods physically move:

Same state as your registered state → charge CGST + SGST, split equally (e.g. an 18% item is 9% CGST + 9% SGST).
Different state, or an export/SEZ supply → charge IGST at the full rate (e.g. 18% IGST) instead.

Read the full rules on our place of supply under GST page. TatvaBooks determines the split automatically from the buyer's GSTIN and place of supply — you never choose it manually.

A filled GST bill — example

Here's what a correctly formatted GST bill looks like for an intra-state sale of ₹50,000 worth of goods at 18% GST, raised by a Pune-based seller to a Pune-based buyer.

Shree Ganesh Traders

FC Road, Pune, Maharashtra — 411005

GSTIN: 27AAAAA0000A1Z5

Invoice No: SGT/2026-27/00142

Date: 02-Jul-2026

Place of supply: Maharashtra (27)

Bill to

Riverside Hardware Pvt Ltd

Kothrud, Pune, Maharashtra — 411038

GSTIN: 27BBBBB1111B2Z6

Description	HSN	Qty	Rate	Taxable value	CGST	SGST
Cement (OPC 43 Grade)	2523	100 Bags	₹500	₹50,000	9% · ₹4,500	9% · ₹4,500

Taxable value: ₹50,000.00

CGST @ 9%: ₹4,500.00

SGST @ 9%: ₹4,500.00

Total: ₹59,000.00

Amount in words: Rupees Fifty-Nine Thousand Only

For Shree Ganesh Traders
Authorised Signatory

If Riverside Hardware were based in Karnataka instead of Maharashtra, the CGST + SGST columns above would collapse into a single IGST @ 18% · ₹9,000 column — same total, different split.

Building this bill yourself — Excel vs software

You can copy this structure into Excel — set up columns for description, HSN, quantity, rate, taxable value, CGST, SGST/IGST and total, with formulas for the tax split. It works for a handful of invoices a month. Where it breaks down: choosing CGST+SGST vs IGST is a manual decision every time, invoice numbering isn't automatically sequential across users, and none of it feeds your GSTR-1 or GSTR-3B. See our bill format in Excel guide for the full column layout.

TatvaBooks generates this exact format for you — no template to maintain. You enter the buyer and the items; the GST split, HSN lookup, running invoice number and amount-in-words are all automatic, and the invoice posts straight into your books and GSTR-1 workings. Free to start on the Solo plan (₹0); the Business plan (₹599/month) adds inventory and e-invoice/IRN preparation.

Frequently asked questions

What is the correct GST bill format?

A GST-compliant tax invoice must carry a consecutive invoice number and date, your name/address/GSTIN, the buyer's name/address/GSTIN (for B2B) and place of supply, an item-wise table with HSN/SAC code, quantity, rate and taxable value, the tax breakup — CGST+SGST for intra-state or IGST for inter-state — the total value in figures and words, and an authorised signature. These are laid down under Rule 46 of the CGST Rules. TatvaBooks fills every one of these fields automatically when you raise an invoice.

Is CGST+SGST or IGST used on a GST bill?

It depends on where the buyer is registered, not where you are. If the seller's state and the buyer's place of supply are the same state, you charge CGST + SGST, split equally (e.g. 9%+9% for an 18% item). If the buyer's place of supply is a different state (or it's an export/SEZ supply), you charge IGST at the full rate instead. Billing the wrong pair is one of the most common GST invoicing mistakes — TatvaBooks decides this automatically from the buyer's GSTIN and place of supply.

Is a GSTIN mandatory on every GST bill?

Your own GSTIN is always mandatory once you're registered. The buyer's GSTIN is mandatory for B2B invoices (registered buyer) and optional for B2C, though it's good practice to capture it if the sale value crosses ₹50,000 and the buyer requests it for e-way bill purposes.

What happens if a GST bill is missing a required field?

A tax invoice missing mandatory fields — like HSN code, place of supply, or a proper sequential number — can be treated as invalid for input tax credit by the buyer, and can attract penalties on the seller during audit. It also breaks GSTR-1 auto-population and e-invoice/IRN generation if you're above the e-invoicing turnover threshold. Getting the format right at the point of billing avoids all of this.

Can I make a GST bill in Excel?

You can, and many small businesses start there — see our Excel bill format guide. The risk is manual GST calculation errors (wrong CGST/SGST vs IGST split), no running invoice-number sequence across users, and no link to your GSTR-1/3B filings. Software like TatvaBooks removes all three: GST is worked out per line automatically, numbering is sequential and tamper-evident, and every invoice flows straight into your return workings.

Do I need to generate this bill format myself every time?

No — that's the point of using GST billing software instead of a template. In TatvaBooks you enter the buyer and items once; the GST-correct tax invoice — with the right CGST/SGST or IGST split, HSN codes and running invoice number — generates itself, every time, free on the Solo plan.

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Generate this GST bill format automatically — no template to maintain.

Enter the buyer and the items; TatvaBooks works out CGST/SGST or IGST, HSN codes and the running invoice number for you. Free to start.

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