Informational
GST Invoice Guide: India Compliance Requirements
April 5, 2026
GST compliance in India isn't optional — and an incorrectly formatted invoice can delay your payment, trigger a tax notice, or cost your client their input tax credit. The rules differ by registration type, service category, and interstate vs intrastate transactions, which makes it confusing to get right the first time. This guide explains every mandatory field required under the GST Act, how to correctly show CGST, SGST, and IGST, when HSN and SAC codes are required, and what the three invoice copies (original, duplicate, triplicate) should each say. If you're a registered business or freelancer working with GST-registered clients, this is your compliance checklist.
Quick Reference Table
| Field | Requirement | Format |
|---|---|---|
| GSTIN | Mandatory for registered businesses | 15 characters |
| HSN/SAC | Harmonized code for items/services | Numeric code |
| Tax Rate | Applicable IGST/CGST/SGST | 5%, 12%, 18%, 28% |
| Invoice Copy | Original, Duplicate, Triplicate | Three copies |
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Create GST Invoicearrow_forwardGST Invoice Requirements in India
In India, GST (Goods and Services Tax) invoices have specific formatting and content requirements mandated by tax authorities. A valid GST invoice must include the 15-digit GSTIN (Goods and Services Tax Identification Number) of both the supplier and recipient, HSN (Harmonized System of Nomenclature) or SAC (Service Accounting Code), GST rates and amounts for each applicable rate, place of supply, and invoice issue date. Non-compliance can result in penalties and rejection of input tax credits.
Quick Reference Table
Use these benchmark pairs for fast sanity checks.
Frequently Asked Questions
What is a GSTIN and do I need one?
GSTIN (Goods and Services Tax Identification Number) is a unique 15-digit identifier assigned by Indian tax authorities to businesses registered under GST. You need a GSTIN if your annual turnover exceeds the threshold (currently ₹40 lakhs for goods businesses or ₹20 lakhs for service businesses). All GST invoices must display both the supplier's and recipient's GSTIN.