GST E-Invoicing Software for Indian Businesses
E-invoicing under GST requires all B2B invoices to be authenticated by the Invoice Registration Portal (IRP) before they are shared with the buyer or used in GST returns. The supplier generates the invoice in their accounting software, uploads the data to the IRP at einvoice1.gst.gov.in, and receives back a digitally signed e-invoice with a unique Invoice Reference Number (IRN) and a QR code. Without a valid IRN, the invoice is not a valid GST document and the buyer cannot claim Input Tax Credit (ITC). E-invoicing currently applies to all B2B supplies by businesses with aggregate annual turnover above Rs. 5 crore (from August 2023).
N D Savla & Associates in Mumbai assists businesses with e-invoicing implementation: selecting the right e-invoicing software, configuring IRP API integration, and ensuring all B2B invoices carry compliant IRN and QR codes. For GST invoice format rules, see our GST Invoicing guide.
E-Invoicing Applicability — Turnover Thresholds
| Effective Date | Businesses Covered by E-Invoicing | Status |
|---|
| 1 Oct 2020 | Turnover above Rs. 500 crore | Active |
| 1 Jan 2021 | Turnover above Rs. 100 crore | Active |
| 1 Apr 2021 | Turnover above Rs. 50 crore | Active |
| 1 Apr 2022 | Turnover above Rs. 20 crore | Active |
| 1 Oct 2022 | Turnover above Rs. 10 crore | Active |
| 1 Aug 2023 | Turnover above Rs. 5 crore — current mandatory e-invoicing threshold | Active — current |
Note: E-invoicing applies to B2B invoices, export invoices, and credit/debit notes only. B2C invoices (supplies to unregistered buyers) do NOT require IRN generation. Businesses above Rs. 500 crore turnover must separately display a dynamic QR code on B2C invoices.
The E-Invoicing Process — Four Steps
- Generate Invoice in Accounting Software — the supplier creates the invoice in Tally Prime, Zoho Books, SAP, or any other software in the standard GST invoice format. No change to data entry.
- Upload to the IRP — invoice JSON is sent to the IRP at einvoice1.gst.gov.in via direct API integration (best for high volume), Excel offline utility, or GSP/ASP middleware. The IRP validates active GSTINs, checks for duplicate IRN, and verifies JSON format.
- IRN and QR Code — the IRN is a unique 64-character hash based on supplier GSTIN, financial year, document type, and document number. The QR code encodes the IRN, both GSTINs, invoice date, value, and HSN of the top 3 line items. The IRP returns a digitally signed JSON; the supplier embeds the IRN and QR code into the printed invoice.
- Auto-Population — e-invoice data auto-populates in the supplier's GSTR-1 without manual entry; for consignments above Rs. 50,000, Part A of the e-way bill is auto-populated; and the e-invoice appears in the buyer's GSTR-2B for ITC claim.
E-Invoicing Software Options
- Tally Prime 3.0+: built-in IRP API integration; configure GSTIN and the e-invoicing module activates
- Zoho Books / Zoho Invoice: native cloud-based IRP integration
- SAP / Oracle / Microsoft Dynamics: built-in e-invoicing modules for large enterprises
- ASP/GSP middleware: for software without native e-invoicing support — the ASP handles JSON conversion and IRP API communication on behalf of the business
- GSTN offline utility: free government Excel-based tool for low-volume bulk IRN generation
Consequences of E-Invoicing Non-Compliance
- Buyer cannot claim ITC: a B2B invoice without a valid IRN is not a valid GST document; ITC is blocked for the buyer
- GSTR-1 not auto-populated: manual entry needed, creating reconciliation risks between the e-invoicing database and GSTR-1
- Section 122 penalty: Rs. 10,000 per non-compliant invoice or the tax involved, whichever is higher
- Commercial dispute with buyer: buyers increasingly insist on e-invoices with IRN as a condition of vendor payment
Frequently Asked Questions — GST E-Invoicing
Our turnover just crossed Rs. 5 crore. When must we start e-invoicing?
E-invoicing applies from the start of the financial year following the year in which aggregate turnover exceeded Rs. 5 crore. If turnover crossed Rs. 5 crore in FY 2024-25, mandatory e-invoicing starts from 1 April 2025. Configure Tally Prime or set up an ASP before that date to ensure every B2B invoice from 1 April onwards carries a valid IRN and QR code.
Can an e-invoice IRN be cancelled?
Yes, within 24 hours of generation, provided no e-way bill has been raised against it. After 24 hours, the IRN cannot be cancelled on the IRP portal. In that case, issue a credit note in the next period to reverse the supply in the books and in GSTR-1. Cancelled IRNs remain in the IRP system marked as cancelled.
Do export invoices need e-invoicing?
Yes. Export invoices issued by businesses above the Rs. 5 crore e-invoicing threshold must carry a valid IRN. The e-invoice auto-populates GSTR-1 and links with ICEGATE for export refund processing, reducing manual data entry in GSTR-1 and the refund portal.