A GST invoice (also known as a “tax invoice” or “GST bill”) is an official document issued by a GST-registered supplier when selling taxable goods or services. It lists all details like what’s sold, how much, taxes charged, and who is involved. This document allows the buyer to claim Input Tax Credit (ITC).
Mandatory Components of a GST Invoice
As per Section 31 of the CGST Act, a GST invoice must include the following fields:
- Supplier details: Name, address, GSTIN
- Invoice number & date: Unique, serially numbered (≤16 characters)
- Recipient details: Name, address, GSTIN (if registered)
- Description of goods/services: Along with HSN (goods) or SAC (services) codes
- Quantity, unit & taxable value
- Tax details: CGST, SGST/UTGST, IGST, and cess with separate amounts
- Place of supply (especially for interstate transactions) and delivery address if different
- Reverse charge mention: If applicable
- Signature or digital signature of supplier or authorized person (not required for e‑invoices)
Optional fields may include payment terms, PO number, transport details, e‑way bill info, etc.
Invoice Issuance Time Limits
- For goods: Before or at time of removal/delivery
- For services: Within 30 days from provision; banks/NBFCs get 45 days
- Special cases:
- Continuous supply of goods: invoice with each delivery or payment
- Continuous supply of services: invoice as specified in the contract or payment date
- Supply on approval: invoice before/at time of supply or within six months of removal
Types of GST Documents
- Tax Invoice: For taxable goods/services
- Bill of Supply: For exempt supplies or composition scheme dealers (without tax details)
- Revised Invoice: When correcting earlier issued invoices (must say “Revised Invoice”)
- Credit/debit notes: Adjust previously issued invoices
- E-invoice: Mandatory for businesses above ₹10 cr (or ₹5 cr per some updates); includes unique IRN & QR code
GST Invoice & Payment Process
- Buyer receives the invoice, then pays the total (including GST).
- The seller remits the GST collected to the government when filing returns.
- The buyer uses the GST details to claim ITC in their returns.
- No payment is required upfront for GST at invoice issue; tax is collected with sale.
Quick Summary
| Feature | Key Points |
|---|---|
| Purpose | Legal proof of sale and ITC claim |
| Who issues | GST‑registered sellers |
| Contents | Supplier & recipient info, goods/services description, HSN/SAC, tax breakup |
| Issue timeline | Goods: before removal; Services: within 30 days |
| Variants | Tax invoice, bill of supply, revised invoice, credit/debit note, e‑invoice |
