What a GST tax invoice must include
Under Rule 46 of the CGST Rules, a tax invoice issued by a registered supplier must contain:
- Supplier's name, address and GSTIN
- A consecutive serial number of up to 16 characters (letters, numbers, hyphen "-" or slash "/"), unique for the financial year, for example INV/26-27/001 (see how to number invoices)
- Date of issue
- Recipient's name, address and GSTIN if registered
- For an unregistered recipient where the value is ₹50,000 or more: name, address, delivery address and the state name and code
- HSN code (goods) or SAC (services) and a description
- Quantity and unit (for goods)
- Total value and taxable value after any discount
- Rate and amount of each tax: CGST, SGST/UTGST, IGST and cess
- Place of supply with state name (required for inter-state supplies)
- Delivery address, if different from the place of supply
- Whether tax is payable on reverse charge
- Signature or digital signature of the supplier or an authorised person
For services, you should generally issue the invoice within 30 days of providing the service.
HSN/SAC digits
| Aggregate turnover (previous FY) | HSN/SAC digits |
|---|---|
| Up to ₹5 crore | 4 digits on B2B invoices (optional on B2C) |
| More than ₹5 crore | 6 digits on all invoices |
GST rates after the 2025 rate rationalisation
The GST Council's reforms, effective 22 September 2025, replaced the 5/12/18/28% structure with two main slabs. The 12% and 28% slabs were removed, and most items moved to 5% or 18%.
| Rate | Applies to |
|---|---|
| 18% (standard) | Most goods and most services, including IT, consulting, design and other professional services |
| 5% (merit) | Many essentials and some services (for example certain hotel stays, gyms and salons) |
| 40% | A short list of luxury and "sin" goods |
| 0% / exempt | Specified essentials and exempt services |
A few special rates (for example on precious metals) and transitional rates on some tobacco products also apply, so always check the current rate notification for your HSN/SAC.
CGST + SGST or IGST?
- Intra-state (supplier and place of supply in the same state): split the rate equally, for example 18% = CGST 9% + SGST 9% (UTGST in Union Territories).
- Inter-state (different states) or exports: charge IGST at the full rate, for example 18%.
Exports of services under a Letter of Undertaking (LUT) are zero-rated. The invoice should carry an endorsement such as "Supply meant for export under LUT without payment of IGST".
GSTIN format
A GSTIN has 15 characters: a 2-digit state code (for example 27 for Maharashtra, 29 for Karnataka), your 10-character PAN, an entity number, the letter Z by default, and a check character. Example: 27ABCDE1234F1Z5.
E-invoicing: who must comply
If your aggregate turnover has exceeded ₹5 crore in any financial year since 2017-18, you must generate e-invoices for B2B supplies and exports by reporting each invoice to an Invoice Registration Portal (IRP). The IRP returns an IRN and a signed QR code, which must appear on the invoice. Since 1 April 2025, taxpayers with turnover of ₹10 crore or more must report invoices within 30 days of the invoice date. Some sectors (such as banks, insurers and SEZ units) are exempt. A PDF from this generator is not an e-invoice. If you are in the mandate, register the invoice on the IRP as well. No lower threshold had been notified at the time of writing, but check the GST portal for updates.
Worked example
A Pune developer bills a Mumbai client for a website (₹85,000), 10 consulting hours at ₹2,500 (₹25,000) and annual hosting (₹12,000). The taxable value is ₹1,22,000.
- Intra-state (Maharashtra to Maharashtra): CGST 9% ₹10,980 + SGST 9% ₹10,980 = ₹21,960, total ₹1,43,960
- Inter-state (client in Karnataka): IGST 18% ₹21,960, total ₹1,43,960
Check splits with our GST calculator.
Common mistakes
- Charging CGST + SGST on an inter-state supply (or IGST on an intra-state one)
- Missing or wrong place of supply and state code
- Invoice numbers longer than 16 characters, or not restarting the series properly each financial year
- Issuing a tax invoice when you are under the composition scheme or supplying only exempt goods (use a bill of supply instead)
- Editing an issued invoice instead of raising a credit note
- Treating a proforma invoice as a tax invoice
How to use this GST invoice template
- Choose a design in the invoice generator or from our invoice templates.
- Add your logo, legal name and address.
- Enter your GSTIN in the Tax ID field, and the client's GSTIN in theirs.
- Add HSN/SAC codes in each line description and set the GST rate. Note the place of supply and the CGST/SGST or IGST split in the notes.
- Download the PDF, then sign it or add a digital signature.
New to invoicing? Read how to write an invoice.
This page is general information, not tax advice. Confirm current rates and notifications on the GST portal or with a chartered accountant.
Frequently asked questions
When do I charge IGST instead of CGST and SGST?
Charge IGST when the supplier's location and the place of supply are in different states (or for exports). Charge CGST and SGST in equal halves when both are in the same state.
Do I need to issue e-invoices?
E-invoicing applies if your aggregate turnover exceeded ₹5 crore in any financial year from 2017-18 onwards, unless your sector is exempt. If you are covered, each B2B invoice must be reported to the IRP to get an IRN and QR code.
How many HSN/SAC digits must I show?
Generally 4 digits on B2B invoices if your previous-year turnover was up to ₹5 crore, and 6 digits on all invoices above ₹5 crore.
What is the GST rate for freelance and IT services?
Most professional and IT services are taxed at the standard 18% rate. Check the rate for your exact SAC, as some services have different rates or exemptions.
Can my invoice number include the financial year?
Yes. Invoice numbers can use letters, numbers, hyphens and slashes, up to 16 characters, and must be unique within the financial year, for example INV/26-27/001.
