Indian GST Invoice Requirements

Overview

A GST invoice is a legally mandated document under India's Goods and Services Tax (GST) regime, serving as evidence of supply and enabling tax compliance and input tax credit (ITC) claims. All GST-registered businesses must issue compliant invoices for taxable supplies.

Mandatory GST Invoice Fields

As per Rule 46 of the CGST Rules, 2017, every GST invoice must include:

1. Supplier details: Name, address, and GSTIN
2. Unique invoice number: Serial, alphanumeric (max 16 characters)
3. Invoice date
4. Recipient details: Name, address, and GSTIN (if registered)
5. Place of supply and state code (for inter-state supplies)
6. HSN/SAC codes: For goods (HSN) or services (SAC)
7. Item descriptions: Clear details of goods/services
8. Quantity and unit price (for goods)
9. Taxable value: After discounts, if any
10. GST rates and amounts: Breakdown of CGST, SGST/UTGST, IGST, and cess
11. Reverse charge applicability: If applicable
12. Signature: Physical or digital signature of the supplier/authorized person

Additional requirements for unregistered recipients (if invoice value > ₹50,000):

• Full name and address
• Delivery address
• State name and code

Types of GST Invoices

1. Tax Invoice

• Issued for taxable supplies
• Must include all mandatory fields above
• Enables ITC claims for recipients

2. Bill of Supply

• Issued for:
  • Exempt/nil-rated supplies
  • Composition scheme dealers
• Does not include tax amounts

3. Revised Invoice

• Issued to correct errors in original invoices
• Must be issued within 1 month of registration certificate issuance (for pre-GST invoices)

4. Invoice-Cum-Bill of Supply

• For mixed taxable and exempt supplies to unregistered customers
• Combines tax invoice and bill of supply details

5. Debit/Credit Notes

• Debit note: When tax/invoice value increases (e.g., corrected tax rate)
• Credit note: When tax/invoice value decreases (e.g., returns, discounts)

E-Invoicing Requirements

Applicability

Mandatory for businesses with:

• Aggregate turnover > ₹5 crore in any financial year (expanded from ₹500 crore in 2023)
• Supplies to SEZs
• Exports/deem exports

Process

1. Generate invoice in JSON format
2. Transmit to Invoice Registration Portal (IRP)
3. Receive unique Invoice Reference Number (IRN)
4. Include IRN and QR code on the invoice

Exemptions

Businesses exempt from e-invoicing include:

• Turnover ≤ ₹5 crore
• Government departments, banks, insurance companies
• Restaurants, hotels, hospitals
• Educational institutions, charitable organizations

Invoice Issuance Timelines

• Goods: Before/at the time of removal for delivery
• Services: Within 30 days of supply (45 days for banks/financial institutions)
• Continuous supply: On/before payment due date or milestone

Consequences of Non-Compliance

• Denial of ITC to recipients
• Penalties under Section 122: ₹10,000 or 100% of tax due (whichever higher)
• Interest liabilities for delayed tax payments
• Increased audit risk and scrutiny from tax authorities

Best Practices

1. Automate invoice generation using compliant software
2. Verify GSTINs of recipients before issuing invoices
3. Maintain invoice serial numbers strictly
4. Use digital signatures for authenticity
5. Reconcile invoices with GST returns regularly

Common Errors to Avoid

• Repeating invoice numbers
• Omitting HSN/SAC codes
• Incorrect tax type (e.g., CGST/SGST vs. IGST for inter-state supplies)
• Missing place of supply details
• Not indicating reverse charge where applicable