E-Invoicing under GST: are you required to generate IRNs?
6 min read · GST
E-invoicing does not mean generating a PDF and emailing it. Under GST it means reporting each B2B invoice to the government's Invoice Registration Portal (IRP), which returns a unique IRN and a signed QR code. Whether you must do this depends on your turnover — here is how applicability works.
Turnover-based applicability
E-invoicing has been rolled out in phases, each phase lowering the aggregate annual turnover threshold above which it becomes mandatory. Applicability is tested against turnover in any preceding financial year from the roll-out onward — so once you cross the threshold in any such year, you stay in scope even if turnover later dips.
The current threshold
As of Sep 2026, the mandate applies to registered persons whose aggregate turnover exceeds ₹5 crore. Because the threshold has been progressively reduced and may be lowered further, do not treat this as permanent — verify the latest CBIC notification (or check with your CA) to confirm the figure and effective date that apply to you.
What the IRN and QR code are
When you report an invoice to the IRP, it validates the data and returns an IRN (a 64-character hash that uniquely identifies the invoice) plus a digitally signed QR code. A B2B invoice that is in scope is not legally valid without the IRN, and the signed QR code must be printed on it. Reporting is per-invoice and near-real-time.
Exempted categories
Even above the threshold, some categories are kept outside the mandate — these have generally included SEZ units (as distinct from SEZ developers), insurers, banks and financial institutions, goods transport agencies, passenger transport operators, and suppliers of admission to cinema exhibitions. The exact exempt list is notified and can change, so confirm your category against the current notification.
How it flows into GSTR-1
One of the main benefits: once an invoice is reported and an IRN issued, its details auto-populate your GSTR-1 (and feed the e-way bill system where relevant). You still review and file the return, but the outward-supply data is pulled from what you already reported to the IRP — which cuts double entry and keeps GSTR-1 and your e-invoices consistent.
OnGravy reports your B2B invoices to the IRP, prints the signed QR code, and carries the data into GSTR-1 automatically.
Try OnGravy →General information, not tax advice. Thresholds and exemptions change — verify against the latest CBIC notification or with your CA.