InvoicingIntermediate⏱ 8 min read🗓 Updated April 2026
How to Generate E-Invoice (IRN) — Step-by-Step Guide - 2026
E-invoicing (electronic invoicing) is mandatory for B2B transactions for businesses with aggregate turnover above ₹5 crore. It involves generating a unique Invoice Reference Number (IRN) from the Invoice Registration Portal (IRP) and embedding a QR code on the invoice. Without a valid IRN, the invoice is not considered valid for ITC purposes by the buyer.
Step-by-Step Process
1
Check Applicability
E-invoicing is mandatory if your aggregate annual turnover (across all GSTINs under one PAN) exceeds ₹5 crore. It applies to B2B invoices, B2G (government) invoices, and export invoices. It does NOT apply to B2C invoices, financial/insurance companies, SEZ units (for supplies TO SEZ), or banking/NBFC companies.
2
Register on IRP Portal
Go to einvoice1.gst.gov.in and register with your GSTIN. If your accounting software has IRP integration, the registration happens automatically when you first push an invoice. API credentials (Client ID and Secret) are generated here for software integration.
3
Prepare the Invoice in Required Format
Your invoice must include all mandatory fields: GSTIN of supplier and recipient, invoice number and date, HSN/SAC code (mandatory for e-invoice), taxable value, GST rate and amount, and place of supply. The data is submitted as a JSON payload to the IRP.
4
Submit to IRP (Portal or API)
Via portal: Login to einvoice1.gst.gov.in → E-invoice → Generate New. Fill the form and submit. Via API/ERP: Your accounting software pushes the invoice data to IRP automatically. Most modern GST-compliant software (Tally, Zoho Books, ClearTax) has built-in e-invoice generation.
5
Receive IRN and QR Code
On successful submission, the IRP returns: IRN (64-character hash), a signed QR code, and the acknowledgement number and date. These must be printed on the invoice. The IRP also auto-populates your GSTR-1 with this invoice data.
6
Print or Share the E-Invoice
Print the IRN and QR code on the physical invoice or the PDF sent to the buyer. The QR code contains key invoice details and can be verified by the buyer using the GST portal's QR verify tool or any QR scanner app.
Pro Tips
E-invoices cannot be amended once an IRN is generated. To correct a mistake, you must cancel the IRN within 24 hours and generate a new one.
IRN cancellation is allowed only within 24 hours and only if the e-way bill linked to that IRN has not been verified at a checkpoint.
B2C invoices are NOT eligible for IRN. Generating an IRN for B2C is not required and not allowed through the standard IRP workflow.
Keep a record of all generated IRNs for your audit trail — the IRP stores IRN data for 24 hours only, after which it is archived.
If IRP is unavailable (downtime), you can generate invoices offline and submit the IRN retrospectively within the allowed window.
Penalty for Non-Compliance
⚠️ Issuing an invoice without a valid IRN (when e-invoicing is mandatory) is treated as not issuing a GST invoice. This attracts a penalty of ₹10,000 per invoice under Section 122 of the CGST Act, or 100% of the tax due — whichever is higher.
Calculate your penalty or interest: Use our free
GST Penalty Calculator to find the exact late fee and interest if you've missed a filing deadline.
Frequently Asked Questions
No. The e-invoice is an additional step — you still issue a regular GST invoice (with all mandatory fields). The IRN and QR code are added to that invoice. The underlying invoice format and mandatory fields remain the same.
Yes. Once an IRN is generated, the IRP pushes the invoice data directly into your GSTR-1. You do not need to enter these invoices again in GSTR-1. This is one of the biggest benefits of e-invoicing.
For FY 2025-26, e-invoicing is mandatory for businesses with aggregate turnover above ₹5 crore in any preceding financial year from FY 2017-18 onwards. The threshold was ₹10 crore until October 2022, then ₹5 crore from August 2023.
