E-Invoicing in India — Complete Guide to the GST E-Invoice System
What is E-Invoicing Under GST?
E-invoicing (electronic invoicing) is a system introduced by the Government of India under the GST framework to standardise and authenticate B2B (business-to-business) invoices. A common misconception is that e-invoicing means generating invoices on a government portal — this is not the case. You continue to generate invoices using your own billing software, accounting system, or even a free tool like BillBanao.
The key difference is that after generating the invoice, you upload its data (in JSON format) to the government's Invoice Registration Portal (IRP) at einvoice1.gst.gov.in. The IRP validates the invoice, generates a unique Invoice Reference Number (IRN), digitally signs the invoice, and adds a QR code. This process creates a tamper-proof, government-validated invoice that can be used for GST return filing.
How Does the E-Invoice System Work?
- Generate Invoice: Create a tax invoice using your billing software (like BillBanao, Tally, or any ERP system).
- Upload to IRP: The invoice data is uploaded to the Invoice Registration Portal in a standardised JSON schema.
- Validation: The IRP validates mandatory fields — GSTIN, HSN codes, tax amounts, and invoice number format.
- IRN Generation: Upon successful validation, a unique 64-character Invoice Reference Number (IRN) is generated using a hash of supplier GSTIN + invoice number + financial year.
- Digital Signature & QR Code: The IRP digitally signs the invoice and generates a QR code containing key invoice details.
- Auto-population in GST Returns: The validated invoice is automatically reflected in GSTR-1 (Table 4A/4B/6B/6C) and the buyer's GSTR-2B. No manual entry required.
E-Invoice Turnover Threshold Timeline
The government has been progressively reducing the e-invoicing threshold to bring more businesses into the system:
| Date | Turnover Threshold | Notification |
|---|---|---|
| October 1, 2020 | ₹500 crore and above | Phase 1 — Large enterprises |
| January 1, 2021 | ₹100 crore and above | Phase 2 |
| April 1, 2021 | ₹50 crore and above | Phase 3 |
| April 1, 2022 | ₹20 crore and above | Phase 4 |
| October 1, 2022 | ₹10 crore and above | Phase 5 |
| August 1, 2023 | ₹5 crore and above | Phase 6 — Current threshold |
Note: The government has indicated plans to further reduce this threshold. Businesses with turnover between ₹1 crore and ₹5 crore should prepare for e-invoicing compliance in the near future.
Who is Exempt from E-Invoicing?
Even if your turnover exceeds the threshold, certain categories of businesses are exempt from e-invoicing:
- SEZ Units (Special Economic Zone units — not SEZ developers)
- Insurers and insurance intermediaries
- Banking companies and financial institutions (including NBFCs)
- Goods Transport Agencies (GTAs)
- Passenger transport services
- Cinema ticket suppliers (multiplex and single-screen)
- Composition Scheme taxpayers — they issue Bills of Supply, not tax invoices
E-Invoice vs Regular Invoice — Key Differences
| Aspect | Regular Invoice | E-Invoice |
|---|---|---|
| Validation | Self-certified by supplier | Validated by government IRP |
| IRN (Reference Number) | Not required | Mandatory — unique 64-char hash |
| QR Code | Optional | Auto-generated by IRP |
| GSTR-1 filing | Manual entry required | Auto-populated from IRP |
| Buyer's GSTR-2B | May have delays | Real-time reflection |
| Cancellation | Flexible | Must cancel on IRP within 24 hours |
| Applicability | All GST-registered businesses | Only above threshold (₹5 Cr) |
How BillBanao Complements E-Invoicing
If your business is below the ₹5 crore threshold, e-invoicing is not mandatory for you. You can use BillBanao's free invoice generator to create fully GST-compliant tax invoices with all mandatory fields — GSTIN, HSN codes, tax breakdowns, place of supply, and more. All invoice generation happens locally in your browser, ensuring your financial data remains private.
For businesses above the threshold, BillBanao can serve as a convenient tool for quickly drafting invoice content before uploading it to your accounting software for IRP submission. The structured output from BillBanao ensures no mandatory fields are missed.
Frequently Asked Questions
What is e-invoicing under GST in India?
E-invoicing is a system where B2B invoices are electronically authenticated by the government's Invoice Registration Portal (IRP). You create invoices in your own software, upload the data to IRP, and receive an Invoice Reference Number (IRN) and digitally signed QR code.
What is the e-invoicing turnover limit in 2026?
As of 2026, e-invoicing is mandatory for businesses with aggregate annual turnover exceeding ₹5 crore in any financial year from 2017-18 onwards. The threshold may be further reduced by the government.
Who is exempt from e-invoicing?
SEZ units, insurers, banking and financial institutions, goods transport agencies, passenger transport services, cinema ticket suppliers, and Composition Scheme taxpayers are exempt from e-invoicing regardless of turnover.
Can small businesses use BillBanao if e-invoicing is not mandatory?
Yes. If your turnover is below the ₹5 crore threshold, you can use BillBanao's free invoice generator for all your GST invoicing needs. It includes all mandatory fields and generates professional PDF invoices.