Last updated: 13 April 2026. If your business crossed Rs 5 crore aggregate annual turnover in any financial year since 2017-18, you need to generate e-invoices for every B2B transaction. That means reporting your invoice data to a government-authorised Invoice Registration Portal (IRP) before issuing it. The IRP validates the details and sends back a unique Invoice Reference Number (IRN) with a digitally signed QR code.
Applicability Note: This guide is based on GST e-invoicing provisions applicable as of 13 April 2026, including CBIC Notification No. 10/2023-Central Tax (Rs 5 crore threshold effective 01 August 2023) and the 30-day reporting mandate for Rs 10 crore+ businesses (effective April 2025). Multi-factor authentication (MFA) became mandatory on the IRP portal from 01 April 2026. Always verify the current position on gst.gov.in or with a GST professional before acting.
Who should care?
- Businesses with aggregate annual turnover (AATO) above Rs 5 crore in any FY since 2017-18
- Growing businesses approaching the Rs 5 crore threshold this financial year
- Accountants and CAs managing compliance for multiple clients
- E-commerce sellers and manufacturers issuing high volumes of B2B invoices
1. What Is E-Invoicing Under GST?
E-invoicing does not mean you generate invoices on a government portal. You still create invoices on your own billing software or ERP. The difference: before issuing the invoice to your buyer, you report the invoice data to an Invoice Registration Portal (IRP) in a standard JSON format (GST INV-01 schema).
The IRP validates the data against GSTN records and returns:
- IRN (Invoice Reference Number) — a unique 64-character hash for each invoice
- Digitally signed QR code — contains supplier GSTIN, recipient GSTIN, invoice number, date, value, HSN codes, and IRN for offline verification
- Signed invoice payload — the validated JSON, digitally signed by the IRP
Without a valid IRN, the invoice is not considered a valid tax invoice under GST. Your buyer cannot claim ITC on an invoice that was required to have an IRN but does not.
2. Who Must Generate E-Invoices? Current Threshold (April 2026)
As per Notification No. 10/2023-Central Tax (dated 10 May 2023, effective 01 August 2023), e-invoicing is mandatory for every GST-registered person whose aggregate annual turnover (AATO) exceeds Rs 5 crore in any financial year from 2017-18 onwards.
| Phase | Turnover Threshold | Effective Date | Notification |
|---|---|---|---|
| Phase 1 | Rs 500 crore+ | 01 October 2020 | No. 61/2020-CT |
| Phase 2 | Rs 100 crore+ | 01 January 2021 | No. 88/2020-CT |
| Phase 3 | Rs 50 crore+ | 01 April 2021 | No. 05/2021-CT |
| Phase 4 | Rs 20 crore+ | 01 April 2022 | No. 01/2022-CT |
| Phase 5 | Rs 10 crore+ | 01 October 2022 | No. 17/2022-CT |
| Phase 6 (Current) | Rs 5 crore+ | 01 August 2023 | No. 10/2023-CT |
Important: The threshold is checked against AATO across all GSTINs under the same PAN. If your turnover crossed Rs 5 crore in FY 2021-22 but dropped below it later, you are still required to generate e-invoices — the obligation is permanent once triggered.
3. Who Is Exempt from E-Invoicing?
As per Notification No. 13/2020-Central Tax and subsequent amendments, the following categories are exempt from e-invoicing even if they cross the turnover threshold:
- SEZ Units (not SEZ Developers — developers must comply)
- Insurance companies
- Banking companies and financial institutions including NBFCs
- Goods Transport Agencies (GTAs) supplying services of transportation of goods by road
- Passenger transportation service providers
- Suppliers of services by way of admission to exhibition of cinematograph films in multiplex screens
If you fall into an exempt category, you can file an E-Invoice Exemption Declaration on the IRP portal to avoid system-generated compliance flags.
4. What Transactions Require E-Invoicing?
E-invoicing applies to:
- B2B supplies — invoices issued to other GST-registered businesses
- Exports — invoices for goods or services exported outside India
- Supplies to SEZ units/developers
- Deemed exports
E-invoicing does not apply to:
- B2C (business-to-consumer) supplies
- Nil-rated and exempt supplies
- Import transactions (covered by Bill of Entry)
- Non-GST supplies (e.g., petroleum products, alcohol for human consumption)
5. The 30-Day Reporting Rule (Rs 10 Crore+ Businesses)
From April 2025, businesses with AATO of Rs 10 crore or more must report invoices to the IRP within 30 days of the invoice date. If you miss this window, the IRP will reject the invoice — you cannot generate an IRN for an invoice older than 30 days.
This means:
- You cannot back-date invoices beyond 30 days
- Delayed invoicing directly impacts your buyer's ITC claim timing
- Your accounting team must upload invoices promptly — batch processing at month-end may no longer work if invoices are dated early in the month
Businesses below Rs 10 crore turnover are currently not subject to this 30-day restriction, but the rule may be extended to lower thresholds in future.
6. MFA on IRP Portal — Mandatory from April 2026
From 01 April 2026, multi-factor authentication (MFA) is mandatory for all taxpayers logging into the IRP and e-way bill portals. When you log in with your credentials, you will be prompted to register for MFA. Login will not be permitted until MFA registration is complete.
Set up MFA now if you haven't already. Waiting until filing day could lock you out of invoice generation when you need it most.
7. How to Start Generating E-Invoices: Step-by-Step
Step 1: Check your eligibility
Calculate your AATO across all GSTINs under the same PAN for every FY since 2017-18. If it exceeded Rs 5 crore in any year, you must comply.
Step 2: Register on the IRP portal
Visit einvoice1.gst.gov.in (or any authorised IRP — einvoice1 through einvoice6). Click "Registration" and enter your GSTIN. The system auto-populates your details from GSTN. Complete MFA setup during registration.
Step 3: Choose your submission method
- Web form — for low-volume invoicing (manual entry on the portal)
- Bulk upload via Excel utility — download the template from the IRP portal, fill in invoice details, and upload
- API integration — for ERP/billing software integration (recommended for regular B2B businesses)
- JSON upload — prepare the invoice in GST INV-01 JSON schema and upload directly
Step 4: Generate the IRN
Submit your invoice data. The IRP validates it and returns the IRN, signed QR code, and signed JSON payload. Embed the IRN and QR code on your invoice before issuing it to the buyer.
Step 5: Verify and share
The e-invoice data auto-populates into your GSTR-1 (Table 4A/6A) and e-way bill (Part A). Your buyer can verify the IRN using the QR code or the "Search IRN" feature on the IRP portal.
8. Penalties for Non-Compliance
Not generating e-invoices when required can attract:
| Violation | Penalty |
|---|---|
| Not issuing an e-invoice (when required) | 100% of tax due or Rs 10,000, whichever is higher — per invoice |
| Issuing an incorrect e-invoice | Up to Rs 25,000 per invoice |
| Transporting goods without valid e-invoice | Goods and vehicle may be detained under Section 129 |
On top of the penalties, invoices without a valid IRN are not considered valid tax invoices. Your buyer cannot claim ITC on those invoices, which will cause problems with your business relationships.
Key takeaways
- E-invoicing is mandatory if your AATO crossed Rs 5 crore in any FY since 2017-18 — even if turnover dropped later
- You generate invoices on your own system but must report them to an IRP for IRN generation before issuing them
- Businesses with Rs 10 crore+ turnover must report invoices within 30 days of the invoice date
- MFA on the IRP portal is mandatory from 01 April 2026 — set it up now
- Non-compliance penalties start at Rs 10,000 per invoice, and your buyer loses ITC
- Banks, insurers, SEZ units, GTAs, and a few other categories are exempt
Frequently asked questions
Is e-invoicing mandatory for businesses below Rs 5 crore turnover?
No. As of April 2026, e-invoicing is mandatory only for businesses with AATO exceeding Rs 5 crore in any FY from 2017-18 onwards (Notification No. 10/2023-CT). However, the threshold may be lowered further — a reduction to Rs 2 crore has been proposed but not yet notified.
Do I need e-invoicing for B2C sales?
No. E-invoicing under Rule 48(4) applies only to B2B supplies, exports, and supplies to SEZ units/developers. B2C invoices are not required to have an IRN.
What happens if I generate an e-invoice after 30 days?
If your AATO is Rs 10 crore or more, the IRP will reject the invoice — you cannot generate an IRN for an invoice dated more than 30 days ago. You will need to issue a fresh invoice with the current date or contact the IRP helpdesk for resolution.
Can I cancel an e-invoice after generating the IRN?
Yes, but only within 24 hours of IRN generation. After 24 hours, you must issue a credit note against the original invoice instead. The credit note itself must also be reported to the IRP if it is a B2B transaction.
Which IRP portal should I use?
There are multiple authorised IRP portals (einvoice1.gst.gov.in through einvoice6.gst.gov.in). All are connected to GSTN and produce the same IRN. Choose based on your preference or your software provider's integration.
Disclaimer: This article is for informational purposes only and does not constitute professional tax advice. GST rules are subject to frequent changes through notifications and circulars. Please consult a qualified tax professional or verify the current provisions on the official GST portal (gst.gov.in) before making any compliance decisions.
Need help setting up e-invoicing for your business? Our GST experts can guide you through IRP registration and integration → gstconsultancy.com