What is e-invoicing under GST? IRN, QR code and who must comply

An e-invoice is a B2B invoice, credit note or debit note whose details you report to the government’s Invoice Registration Portal (IRP) before you issue it. You still make the invoice in your own accounting software, such as TallyPrime. The IRP checks the details and returns an Invoice Reference Number (IRN), an acknowledgement number and date, and a digitally signed QR code, which you print on the invoice. As of November 2026, e-invoicing applies to every business whose aggregate turnover crossed ₹5 crore in any financial year from 2017-18 onwards.

Who must e-invoice

The test is your aggregate turnover: the combined turnover of all GSTINs registered under the same PAN, anywhere in India. If it crossed ₹5 crore in any financial year from 2017-18 onwards, you must e-invoice from the next 1 April. The duty stays even if turnover falls later, because the test looks at every earlier year.

Example: a steel trader in Bengaluru had ₹3.4 crore of turnover on its Karnataka GSTIN and ₹1.9 crore on its Tamil Nadu branch GSTIN in 2025-26. Aggregate turnover is ₹5.3 crore, so both GSTINs must e-invoice from 1 April 2026.

Some businesses are exempt, for example banks, insurance companies and NBFCs, goods transport agencies, passenger transport services, multiplex cinema admissions, government departments and local authorities, and SEZ units (SEZ developers are not exempt). Check the latest notification for the full list.

What e-invoicing covers

Document	Needs an IRN?
Tax invoices to registered buyers (B2B)	Yes
Credit and debit notes to registered buyers	Yes
Export invoices, with or without IGST	Yes
Supplies to SEZ units and developers	Yes
Deemed exports	Yes
Invoices to your own branch in another state (a different GSTIN)	Yes, it is a supply
Sales to unregistered buyers (B2C)	No
Delivery challans, for example for job work	No
Bills from foreign suppliers for your imports	No

B2C sales stay outside e-invoicing. A separate rule asks businesses with turnover above ₹500 crore to print a dynamic QR code on B2C invoices, so that customers can scan it and pay.

The IRN, acknowledgement and QR code

• The IRN is a 64-character reference that the IRP builds from your GSTIN, the financial year, the document type and the document number. The same document number cannot get a second IRN in that year.
• The acknowledgement number and date record when the IRP registered the document.
• The signed QR code carries the key details: supplier and buyer GSTINs, document number and date, invoice value, number of items, main HSN code, and the IRN with its date. Anyone can scan it to check that the invoice was registered.

You share the invoice with your buyer as usual, with the IRN and QR code printed on it.

How it works, step by step

1. Raise the invoice in your accounting software as usual.
2. Send its details to the IRP in the government’s format, through the e-invoice portal, your software or a GST Suvidha Provider (GSP).
3. The IRP checks the GSTINs, duplicates, HSN codes, totals and dates.
4. It returns the IRN, the acknowledgement and the signed QR code.
5. Print them on the invoice and share it with the buyer.
6. The IRP passes the data on. It appears in your GSTR-1, and if you gave transport details, the e-way bill can be generated from the same data.

Cancelling or correcting an e-invoice

You can cancel an IRN within 24 hours of generating it, and only for the whole document. Partial cancellation is not allowed. If an e-way bill is active for the invoice, cancel the e-way bill first.

After 24 hours the IRP will not cancel it. Issue a credit note, which is itself an e-invoice, to reverse it fully or partly. A cancelled invoice number cannot be used again for a new IRN, so give the corrected invoice a fresh number.

The IRP does not let you edit a registered invoice either. Changes to price or quantity go through credit or debit notes.

How e-invoices flow into GSTR-1

Registered invoices and notes are filled into the right tables of your GSTR-1 automatically: B2B, credit and debit notes, and exports. Cancelled IRNs drop out. You still need to:

• review the auto-filled data before filing;
• add what e-invoicing does not cover, such as B2C sales, nil-rated supplies, the HSN summary and the documents-issued table;
• file GSTR-1 by the due date, because your buyers see these invoices in their GSTR-2B only after you file.

More in GSTR-1 explained.

Common e-invoice errors and fixes

Error	Usual cause	Fix
Duplicate IRN	The same number reported twice, or a cancelled number reused	Use the IRN already issued; give new invoices new numbers
Invalid buyer GSTIN	A typing mistake, or the buyer’s registration is cancelled	Check the GSTIN on the GST portal and correct the party master
Invalid HSN code	Code missing, too short or not in the official list	Use a valid code; businesses above ₹5 crore need at least 6 digits
Totals do not match	Rounding, discounts or wrongly set up tax ledgers	Correct the voucher so items plus tax equal the invoice value
Wrong tax type	IGST on a sale within the state, or CGST and SGST on an inter-state sale	Check the place of supply and tax ledgers
PIN code does not match the state	Wrong address in the party master	Correct the address
Invalid document number	More than 16 characters, or characters other than letters, digits, / and -	Fix the numbering series
Document too old	Reported more than 30 days late by a ₹10 crore+ business	See the 30-day e-invoice rule

How Auditer helps

Under Settings, Auditer asks the Owner whether turnover crossed ₹5 crore and whether it is ₹10 crore or more, then whether e-invoices are generated in TallyPrime (Auditer shows the result) or by Auditer through a GST Suvidha Provider, manually or automatically after each sync. Sales to unregistered buyers are left out of the list, with a count. The IRN and signed QR code are printed on the invoice, and the IRN is written back into the TallyPrime voucher. When the portal refuses an invoice, Auditer shows its reason, a refused invoice dated today can be corrected, and the 2 credits for that e-invoice are returned. See GST compliance.

This article is general information, not tax advice. GST rules change; check the GST portal or your tax professional before acting.