Glossary · GST & Indirect Tax
IRN
A unique, hash-based identifier issued by the Invoice Registration Portal for a GST invoice under the e-invoicing system.
Under GST e-invoicing, an invoice in the prescribed format is uploaded to the Invoice Registration Portal (IRP), which validates it and returns an Invoice Reference Number (IRN) together with a digitally signed copy and a QR code. The IRN uniquely identifies that invoice, and the signed details flow into the supplier’s GST returns so the recipient can verify the invoice.
Examples
A registered supplier obtains an IRN for a B2B tax invoice; the buyer scans the printed QR code to confirm its authenticity.