What it means
When an e-invoice is reported, the portal builds a hash from four things: the supplier’s GSTIN, the financial year, the document type and the document number. That hash is the IRN. Because it is built from the invoice number, the portal can refuse the same number twice in a year. With the IRN the portal returns an acknowledgement number and date, and a signed QR code that holds the key invoice details.
Example
Kaveri Agencies reports invoice KA/26-27/0412 dated 3 Nov 2026. The portal returns:
| Item | What comes back |
|---|---|
| IRN | a 64-character code, for example 6f1c…e29a |
| Ack no. and date | a 15-digit number, 3 Nov 2026 |
| Signed QR code | printed on the invoice |
A buyer or a tax officer can scan the QR to check the invoice is genuine.
Common mistakes
- Re-using the invoice number after a cancellation. The portal does not accept the same number again for that year.
- Waiting more than 24 hours to cancel. After that the IRN stays; correct the sale with a credit note, which gets its own IRN.
- Printing the QR from another tool and not storing the IRN in your books, so GSTR-1 and the books disagree.
In MyRecords
MyRecords creates the e-invoice upload file and records the IRN, acknowledgement and signed QR on the invoice, so the print carries them; the upload file uses the same tax figures as the GSTR-1 file. A cancellation within 24 hours is recorded too. Getting the IRN straight from the invoice is available once you connect your e-invoice API login, from NIC or a GST Suvidha Provider.