GST Invoice India — Format, Rules & Free Template

A GST invoice is not just a billing document in India — it is a legal requirement under the Goods and Services Tax Act and a critical document for your buyers to claim input tax credit (ITC). Getting the format wrong means your client cannot claim ITC, which damages the business relationship and can result in notices from the GST department. This guide covers the mandatory GST invoice format, who needs to issue one, how CGST/SGST/IGST works, and how to create a correct GST invoice for free.

Who Needs to Issue a GST Invoice?

You are required to issue a GST invoice if you are a registered GST taxpayer supplying taxable goods or services. GST registration is mandatory when your aggregate annual turnover exceeds:

• ₹20 lakhs for most states (for services)
• ₹40 lakhs for goods suppliers in most states
• ₹10 lakhs for special category states — Manipur, Mizoram, Nagaland, Tripura

If you supply goods or services across state borders (inter-state supply), GST registration is compulsory regardless of turnover, and you must issue invoices with IGST applied.

If you are below the turnover threshold and not registered, you cannot issue a GST invoice or charge GST. Instead, issue a regular invoice without any tax component.

Mandatory GST Invoice Format — What to Include

Rule 46 of the CGST Rules 2017 specifies the mandatory fields for a GST tax invoice. Every registered business must include all of the following:

• Name, address, and GSTIN of the supplier
• Consecutive invoice number — unique within a financial year (e.g. INV/2026-27/001)
• Date of issue
• Name, address, and GSTIN (or UIN) of the recipient — for B2B transactions
• HSN code (for goods) or SAC code (for services)
• Description and quantity of goods, or description of services
• Total value of supply
• Taxable value after discounts
• Applicable GST rate (e.g. 5%, 12%, 18%, 28%)
• Amount of CGST, SGST (for intra-state) or IGST (for inter-state)
• Place of supply (state name and code)
• Whether the tax is payable on a reverse charge basis
• Signature or digital signature of the supplier or their authorized representative

CGST, SGST, and IGST — Which Tax to Apply?

This is the most confusing part of GST invoicing for new registrants. The rule is straightforward once you understand it:

The total tax burden is the same whether CGST+SGST or IGST applies — the difference is only in how the tax revenue is split between the central and state governments.

HSN and SAC Codes — Do You Need Them?

Yes, HSN (Harmonized System of Nomenclature) codes for goods and SAC (Services Accounting Code) codes for services are mandatory on GST invoices. The number of digits required depends on your annual turnover:

• Turnover up to ₹5 crore: 4-digit HSN/SAC code
• Turnover above ₹5 crore: 6-digit HSN/SAC code
• Exports: 8-digit HSN code mandatory

Common SAC codes for freelancers and service providers:

• 998314 — IT and software development services
• 998361 — Digital marketing and advertising services
• 998411 — Accounting, bookkeeping, and auditing services
• 999299 — Other miscellaneous services not elsewhere classified
• 998313 — Graphic design and other creative services

GST Invoice Format — Sample

Here is what a correctly formatted GST invoice looks like for an intra-state service transaction at 18% GST:

How to Create a GST Invoice in India — Step by Step

1. 1
   Open the InvoFree GST Invoice GeneratorGo to invoicemakerfree.org/gst-invoice-generator/. No account or email required — the form loads instantly.
2. 2
   Enter your GSTIN and business detailsFill in your registered business name, address, and 15-digit GSTIN in the "From" section. Your GSTIN must match your GST registration exactly.
3. 3
   Add the recipient's detailsEnter the client's name, address, and GSTIN (for B2B). For B2C, GSTIN is not required but include the client's state for place of supply.
4. 4
   Add your invoice number and dateUse a sequential invoice number within the financial year — e.g. INV/2026-27/001. Never reuse invoice numbers.
5. 5
   Add line items with HSN/SAC codesEnter each service or product with its SAC or HSN code, quantity or description, and taxable value.
6. 6
   Set the correct GST rate and typeSelect the applicable GST rate (5%, 12%, 18%, or 28%). Choose CGST+SGST for intra-state or IGST for inter-state transactions.
7. 7
   Download PDF and share with your clientClick Download PDF. Keep a copy for your GST return filing (GSTR-1). Send to your client so they can claim input tax credit.

GST for Freelancers Exporting Services

If you are an Indian freelancer providing services to clients outside India — on Upwork, Fiverr, or directly — your services qualify as exports and are zero-rated under GST. This means:

• You do not charge GST on your invoices to foreign clients
• You must have a GST registration (if above the turnover threshold) and file returns
• You can claim a refund of GST paid on your business inputs (like software, equipment, office expenses)
• Payment must be received in foreign currency and converted through a bank — this is important for export eligibility

The place of supply for export of services is outside India, making it an inter-state supply technically — but taxed at zero rate, not 18% IGST.

Common GST Invoice Mistakes to Avoid

• Missing GSTIN: A GST invoice without your GSTIN is invalid. Your client cannot claim ITC on it.
• Wrong CGST/SGST vs IGST: Applying IGST on an intra-state transaction (or vice versa) is a compliance error and requires a credit note and revised invoice to fix.
• No HSN/SAC code: Mandatory for all registered taxpayers. Leaving it blank or using the wrong code triggers notices.
• Non-sequential invoice numbers: Invoice numbering must be consecutive within a financial year. Gaps or reused numbers attract scrutiny during audits.
• Incorrect place of supply: Always state the recipient's state as the place of supply for services, unless specific place of supply rules override this.
• Not filing GSTR-1: Every GST invoice you issue must be reported in your GSTR-1 return by the due date. Failing to do so blocks your client's ITC claim.

GST Invoice vs Bill of Supply

A GST invoice is issued when GST is applicable on the transaction — i.e., for taxable goods and services supplied by a registered taxpayer.

A Bill of Supply is issued instead of a GST invoice when GST does not apply — specifically for:

• Exempted goods or services (where GST rate is nil)
• Composition scheme taxpayers (who cannot charge GST from customers)

A Bill of Supply looks similar to a GST invoice but must include the statement "Amount of tax not to be taken" and does not show any tax amounts. If you are on the composition scheme, always issue Bills of Supply — never GST invoices.