E-invoicing is not a different invoice format. It is a requirement that your invoice be registered with a government portal before it is issued, and that it carry the Invoice Reference Number and QR code that come back. An invoice that should have been registered and was not is not a valid tax invoice, and your customer cannot take credit on it.
Starting at
₹4,999 onwards
E-invoicing
Businesses above ₹5 crore aggregate turnover
Timeline
Enablement in days; integration varies
E-invoicing is mandatory for a registered person whose aggregate annual turnover exceeds ₹5 crore in any financial year from 2017-18 onwards, a threshold in force since 1 August 2023. The test is applied at PAN level, not GSTIN level - a business with registrations in Maharashtra, Karnataka and West Bengal aggregates turnover across all three, and once the combined figure crosses ₹5 crore every registration under that PAN is covered. Once you cross it in any financial year from 2017-18 onwards, you stay covered; turnover falling back below ₹5 crore in a later year does not take you out.
TL;DR
Covered: tax invoices, credit notes and debit notes for B2B, SEZ, deemed export and export supplies. Not covered: B2C invoices, and certain notified suppliers including SEZ units, banks, insurers, GTAs, passenger transport and multiplex operators. Some sites claim the threshold dropped to ₹2 crore from October 2025 - there is no notification supporting that. The threshold is ₹5 crore.
IRN
Invoice Reference Number, returned by the Invoice Registration Portal when an invoice is registered. Without it the document is not a valid tax invoice under Rule 48(5).
IRP
Invoice Registration Portal - where invoices are reported, by direct upload, offline utility or API integration through a GSP.
30-day rule
From 1 April 2025, taxpayers at or above ₹10 crore turnover cannot report a document to the IRP more than 30 days after the document date. The IRP rejects it.
Aggregate turnover at PAN level
Turnover is summed across every GSTIN under the PAN, not tested registration by registration.
E-invoicing is mandatory, but the 30-day reporting restriction is not currently imposed on this group.
The 30-day reporting rule applies, effective 1 April 2025. This threshold was previously ₹100 crore.
Under a GSTN advisory dated 17 June 2026. If your ERP has not been updated for the Ship-to GSTIN field, IRN generation will start failing.
01
Aggregate turnover computed at PAN level across every financial year from 2017-18 onwards.
02
The GST portal shows enabled status. Where a taxpayer has crossed the threshold but is not showing as enabled, self-enablement is available on the IRP.
03
Direct upload on the IRP for low volume, the offline utility for medium, or API integration through a GSP for volume.
04
Tally, Zoho Books, Busy or a custom ERP mapped to the e-invoice schema, tested on the IRP sandbox before going live. We then check the downstream: IRN data auto-populates GSTR-1 and Part A of the e-way bill, and both need checking rather than assuming.
Upload via our secure portal. We pre-check every scan before filing - cuts portal rejections by ~90%.
Still unsure if E-invoicing is right for your case? Book a free 20-minute consult - a senior CA / CS will walk you through your specifics.
Still have questions?
Book a free 20-minute consult with a senior partner - we'll walk through your case and outline next steps.
Talk to a partner →A senior CA / CS will get on a call with you, confirm scope and start the work - usually within 24 hours.
