GST Invoice Format India 2026: Complete Rules, Fields & Free Template

What is a GST Invoice?

A GST invoice is a tax-compliant document issued by a registered seller to a buyer in India. Under the Goods and Services Tax Act, 2017, any business with GST registration must issue an invoice that meets specific format requirements.

If you're a freelancer in Bengaluru, a manufacturer in Pune, or a Shopify seller in Delhi — this guide explains exactly what your invoice must contain in 2026.

Mandatory Fields in a GST Invoice

According to Rule 46 of the CGST Rules, every GST invoice must include:

Invoice number — sequential, unique per financial year, max 16 characters.

2. Date of issue.

3. Supplier's name, address & GSTIN.

4. Buyer's name, address, and GSTIN (if registered).

5. HSN code (for goods) or SAC code (for services).

6. Description, quantity, unit and total value of goods/services.

7. Taxable value, discount and rate of tax.

8. Amount of tax — split into CGST + SGST or IGST.

9. Place of supply (state).

10. Whether tax is payable on reverse charge.

11. Signature of the supplier (or digital signature).

CGST + SGST vs. IGST: Which Applies?

Intra-state sale (same state) → charge CGST + SGST, split 50/50.

Inter-state sale (different state or UT) → charge IGST at the full rate.

Export of goods/services → IGST at 0% (zero-rated under LUT) or claim refund.

> Example: A Karnataka seller billing a Karnataka client at 18% → 9% CGST + 9% SGST.

> A Karnataka seller billing a Maharashtra client at 18% → 18% IGST.

GST Rate Slabs (2026)

| Rate | Examples |

| --- | --- |

| 0% / Exempt | Fresh produce, books, healthcare |

| 5% | Essentials, transport, small restaurants |

| 12% | Processed food, computers, business class travel |

| 18% | Most services (IT, consulting, SaaS), telecom |

| 28% | Luxury goods, cars, sin items |

Common Mistakes to Avoid

Wrong place of supply — leads to wrong CGST/SGST vs IGST split and notice from GST officer.

2. Missing HSN code — mandatory for businesses with turnover above ₹5 crore (6-digit HSN).

3. Non-sequential invoice numbers — series must be continuous and reset each financial year.

4. Skipping reverse charge declaration — important for services from unregistered vendors.

Get a Free GST Invoice Template

[FreeBiller's invoice editor](/editor) ships with a built-in GST template. It auto-calculates CGST/SGST/IGST based on the state you enter and lets you add HSN codes, GSTIN and place of supply in seconds — completely free, with no signup.

You can also use our [free GST Calculator](/gst-calculator) to instantly compute the tax breakdown for any amount.