e-Invoicing and IRN
IRNIndia's electronic invoicing system under GST, in which B2B invoices above a notified turnover threshold must be reported to the Invoice Registration Portal which returns a unique Invoice Reference Number and a signed QR code.
Indian e-Invoicing was rolled out in phases starting October 2020. As of 2026 it applies to all GST-registered businesses with aggregate annual turnover above ₹5 crore. For every B2B invoice within scope, the supplier must submit invoice JSON to the Invoice Registration Portal (IRP), which validates the data and returns an Invoice Reference Number (IRN) plus a signed QR code that must be printed on the invoice.
The IRP-validated invoice data flows automatically into the supplier's GSTR-1 and the recipient's GSTR-2B, reducing reconciliation drift between books and tax filings. From a reconciliation perspective this is structurally helpful: e-invoiced transactions are far less prone to GSTR-2B mismatches than non-e-invoiced ones.
The reconciliation patterns that remain: invoices generated but not yet IRN-registered (a process exception), invoices registered but cancelled within 24 hours (the only window in which cancellation is allowed via the portal), and the once-common pattern of duplicate IRNs from manual retry which the IRP now actively prevents.