GST e-Invoicing

GST e-Invoicing has, by 2026, completed its journey from a B2B compliance for the largest taxpayers to a near-universal mandate. Under Notification No. 13/2020-Central Tax (as amended), e-invoicing is mandatory for any registered person whose aggregate turnover crossed ₹5 crore in any preceding financial year from FY 2017-18 onwards, for all B2B supplies, SEZ supplies, exports, and deemed exports. The threshold has been progressively reduced from ₹500 crore (October 2020) to ₹100 crore (January 2021) to ₹50 crore (April 2021) to ₹20 crore (April 2022) to ₹10 crore (October 2022) to ₹5 crore (August 2023) — and is widely expected to fall further toward ₹1 crore over the policy horizon.

The architecture is unique. Every B2B tax invoice must be reported in real time to the Invoice Registration Portal (IRP) — a network of certified portals (NIC IRP, ClearTax IRP, IRIS IRP, etc.) — which validates the invoice against the prescribed JSON schema, assigns a unique Invoice Reference Number (IRN), and embeds a QR code with the digitally signed invoice. Only an invoice with a valid IRN is a legally valid tax invoice for ITC purposes — Section 31 read with Rule 48(4) makes this explicit. An invoice without IRN, where IRN was required, is treated as not having been issued, denying ITC to the recipient and triggering Section 122 / 125 penalty for the supplier.

We design, integrate, and operate e-invoicing for ₹5 crore+ businesses — across NIC IRP and private IRPs, with ERP integration, schema mapping, GSTR-1 auto-population, e-Way Bill auto-generation, and exception handling.

What e-Invoicing Actually Changes

Real-time IRP push: Every B2B / SEZ / export / deemed-export invoice is reported to IRP at issue (or before despatch); IRN + QR code returned in 1-2 seconds; printed on the physical / PDF invoice.

GSTR-1 auto-population: Invoices reported to IRP flow into GSTR-1 of the supplier and GSTR-2A / 2B of the recipient automatically — manual GSTR-1 invoice entry replaced by reconciliation.

e-Way Bill auto-generation: Where transport details are populated at IRP stage, EWB Part A is auto-generated; Part B (vehicle) is added on the EWB portal.

Section 31 + Rule 48(4) compliance: An invoice without IRN (where required) is not a valid tax invoice — ITC denial to recipient, Section 122 penalty to supplier, GSTR-1 mismatch.

The e-Invoicing Schema (INV-01)

The JSON schema published by GSTN — e-Invoice Schema (Version 1.1 / 2.0 series) — has 12 mandatory sections and ~150 optional fields. Common failure points: GSTIN format, HSN at 6-digit / 8-digit (mandatory for ₹5 crore+ from April 2024), place of supply, ship-to vs bill-to distinction, reverse charge flag, export type (with payment / without payment / SEZ), document type (INV / CRN / DBN). A single schema mismatch rejects the IRN — and at scale, even a 1% rejection rate becomes a daily fire-drill.

Common e-Invoicing Failures We Fix

Threshold trigger missed: Turnover crossed ₹5 crore in a past FY but e-invoicing not started — back-dated non-compliance, ITC challenges from recipients.

ERP not integrated: Invoices generated in ERP, IRP done in parallel — duplicate entry, mismatch, manual cancellation chaos.

Cancellation timing: IRN can only be cancelled within 24 hours of generation, and only if no EWB has been generated against it; beyond 24 hours, only credit note can correct.

Recipient ITC denied due to supplier IRN gap: Recipient sees the invoice in books but not in GSTR-2B because supplier did not generate IRN — Rule 36(4) / Section 16(2) ITC denial follows.