What Is e-Invoicing Under GST 2025: Process, Benefits & FAQs

What is e-invoicing under GST?

e-Invoicing in the GST regime is a landmark shift from paper or PDF based B2B invoicing to a fully digital, centrally reported system. Since its rollout in October 2020, every invoice between registered businesses must be generated in a structured JSON format and sent to a government-maintained Invoice Registration Portal (IRP). This single source of truth replaces disparate formats, cuts down on manual data-entry errors and speeds up processes like GSTR-1 filing and e-way-bill creation. At its core, e-Invoicing aims to:

• Standardize data so that every invoice carries the same fields in the same format—no more missing line-items or mismatched date stamps.
• Automate reporting, letting your accounting software push invoice details directly into tax returns and logistics portals without repetitive uploads.
• Prevent fraud by issuing each invoice a unique, tamper-proof reference number (IRN) with a digital signature and QR code.

By anchoring invoice data on the IRP, companies see dramatic reductions in reconciliation time, faster credit-claim cycles and a stronger compliance framework for India’s indirect-tax ecosystem.

How Has the e-Invoicing Regulatory Framework Evolved?

The journey began when the GST Council, seeking to clamp down on fake invoices and streamline compliance, approved mandatory e-Invoicing. The Central Board of Indirect Taxes & Customs then released detailed notifications, laying out the legal and technical foundations. Instead of a one-size-fits-all launch, authorities opted for a phased approach based on turnover:

• October 2020: Companies with turnover above ₹500 crore
• January 2021: Extended to ₹100 crore+
• July 2021: Covered ₹50 crore+
• January 2022: Brought in ₹20 crore+
• October 2022: Captured ₹10 crore+
• August 2023: Lowered to ₹5 crore+, making e-Invoicing nearly universal for B2B transactions

Alongside these phases, timing rules evolved. Initially, invoices had to reach the IRP within 7 days—but busy finance teams and occasional portal outages meant many missed that window. In November 2023, the deadline stretched to 30 days for businesses ≥₹10 crore, and as of April 2025 that same 30-day window applies to all firms ≥₹5 crore. A more recent tweak (effective June 2025) treats invoice numbers in a case-insensitive way, eliminating duplicate rejections caused by letter-case mismatches.

Applicability & Exemptions of e-Invoices Under GST

Today, any GST-registered business whose annual turnover exceeds the notified threshold must generate its B2B invoices in the prescribed JSON format and submit them to the IRP. The mandate covers:

• Tax Invoices for supplies to other registered entities
• Credit and Debit Notes linked to those invoices (per Section 34 of the CGST Act)
• Exports, deemed exports and consignments to SEZ units (all zero-rated under GST)
• Government-to-Business (B2G) purchases where the buyer uses its GSTIN

However, several categories remain outside the e-Invoicing ambit:

• Composition-scheme suppliers, who file quarterly returns
• Passenger transport operators, insurers, banks/NBFCs and goods-transport agencies
• B2C transactions and nil-rated or fully exempt supplies

This carve-out ensures small traders and specialized services aren’t forced into complex compliance, while preserving the core B2B benefits of the system.

What Is the Step-by-Step Process for Generating an GST e-Invoice?

1. Data Standard & Schema for for e-Invoicing:

Your ERP or invoicing software generates a JSON payload that follows a global, PEPPOL-aligned schema. This schema enforces over 100 mandatory fields—everything from invoice number and date to HSN/SAC codes, tax breakup and “ship-to” details. By adhering to this standard, you eliminate format mismatches and downstream reconciliation headaches.

2. Invoice Registration Portal (IRP) Validate and Process GST e-Invoices:

• Upload: Send your JSON file via direct API call, through a GST Suvidha Provider (GSP), the IRP’s web or mobile interface—or even by SMS for very low volumes.
• Validation & IRN Generation: The portal checks your schema compliance and searches for duplicate keys by hashing your GSTIN, invoice number and financial year. On success, it issues a unique Invoice Reference Number (IRN), appends a digital signature and generates a QR code containing key invoice details.
• Auto-Forwarding: The IRP automatically pushes your invoice data into the GSTR-1 draft and the e-way-bill system, eliminating manual entry in those portals.

3. Different Modes of Generation e-Invoices

• ERP/API Integration: Ideal for high-volume enterprises needing real-time automation.
• GSP-Based Connectivity: Plug-and-play simplicity with managed updates.
• Offline Tools: Excel or JSON converters for occasional users or in offline scenarios.
• Mobile/SMS: Lightweight options for on-the-go invoicing.

Which Key Components and Fields Must Be Included in a GST e-Invoice?

A compliant GST e-Invoice JSON is organized into five core sections, with two optional Annexures:

1. Document Details: Invoice type, placeholder for IRN, invoice number and date.
2. Supplier Information: GSTIN, legal and trade names, address and state code.
3. Recipient Information: GSTIN or unique ID, name, address and supply type.
4. Line Items: An array listing each product or service with its HSN/SAC code, description, quantity and rate.
5. Totals & Taxes: Taxable value, detailed breakup of CGST, SGST and/or IGST, and the grand total.

Optional Annexures can include discount breakdowns, additional charges or buyer reference fields—helpful for richer data but not strictly enforced.

Among the 30+ critical fields are your GSTINs, IRN, invoice number/date, HSN/SAC codes, assessed values, tax splits, total amount, supply type, and “ship-to” details (name, GSTIN, address, PIN and state).

To get started, download the sample JSON template from your ERP or GSP, and refer to the official schema on the e Invoice portal (https://einvoice.gst.gov.in). Mapping these fields correctly upfront prevents common validation errors on first upload.

What are Time Limits & Reporting Rules for e-Invoicing?

Originally, all invoices had to hit the IRP within 7 days—but that tight window often clashed with workload peaks and portal hiccups. In response, the 7-day rule became a 30-day window in two stages:

• Nov 2023: Taxpayers ≥₹10 crore gained up to 30 days.
• Apr 2025: Same 30-day window for those ≥₹5 crore.

Although missing the deadline doesn’t instantly trigger a penalty, repeated delays can invite audit scrutiny or late-filing fees under Sections 47 and 50 of the CGST Act.

Pro Tip: Implement a simple log that timestamps invoice creation versus IRP acknowledgment—if your average lag exceeds 48 hours, you may need improved API capacity or batch-upload routines.

What Are the Major Benefits of e-Invoicing for Businesses?

1. Up to 80% less data-entry time: Automated drafts of GSTR-1 and e-way bills save finance teams 4–6 hours per filing cycle.
2. Over 98% fewer reconciliation mismatches: A single source of truth eradicates typos in invoice numbers or GSTINs.
3. Faster working capital: Buyers see your invoices in their GSTR-2A within minutes, accelerating ITC claims and payment approvals.
4. Stronger business trust: QR-code-verified dispatch confirmations reduce “invoice not received” disputes.
5. Live audit trails: Every IRN is timestamped and digitally signed, making it easy for authorities to spot tampering.
6. Fraud detection: Central data flags suspicious invoice clusters; pilot sectors report a 60% drop in fake-invoice claims.
7. Policy insights: Aggregated data helps the GSTN forecast revenue and pinpoint compliance hotspots.

What Challenges Do Companies Face When Implementing e-Invoicing?

Rolling out GST e-Invoicing is a strategic project—here’s what to watch for:

• ERP Field Mapping: Every internal field must align with the e invoice portal’s schema. Missing parameters lead to rejections.
• Schema Versioning: The IRP schema updates periodically. Schedule quarterly reviews to ingest changes.
• API Performance: High-volume exporters may hit thousands of invoices per hour—negotiate SLAs with your GSP or cloud provider to avoid bottlenecks.
• Error-Handling & Retries: Automate retries with exponential back-off for network timeouts or duplicate-key errors, and set up alerts for persistent failures.
• Team Training: Equip finance, sales and customer-service teams with quick-reference guides for handling “Pending,” “Rejected” or “Cancelled” statuses.

For example, one auto-parts manufacturer trimmed its IRP rejection rate from 12% to 1% in just two months by running daily schema checks in a QA environment and maintaining a shadow-upload queue.

Conclusion

e-Invoicing transforms what was once a compliance burden into a streamlined, reliable part of your finance workflow. By standardising data, automating reporting and strengthening fraud controls, it frees your teams to focus on strategy, not spreadsheets—and helps build a more transparent, efficient indirect-tax landscape for everyone.

Frequently Asked Questions

1.  Can I cancel or modify an e-Invoice After submission?

You must void the entire IRN within 24 hours via the IRP. After that window, cancellations happen through your GSTR-1 amendment and you issue a fresh invoice.

2. Do You Still Need an e-Way Bill If You Use e-Invoicing?

Yes—Part A of the e-way bill auto-fills from the IRP, but you must complete Part B with transporter details before dispatch.

3. What Should You Do If the e-Invoice Portal Is Down?

Use your GSP’s offline batch mode or the Excel/JSON converter. Those tools queue invoices for automatic submission when the IRP recovers—ensuring you still meet the 30-day deadline.

4. Are e-Invoices Required for B2C or Unregistered Buyers?

No. The mandate applies only to B2B, B2G, exports, deemed exports and SEZ supplies. However, very large taxpayers (₹500 crore+) must still generate a dynamic QR code for all invoices to support traceability.

5. What Are the Penalties for Late e-Invoice Reporting?

A late fee of ₹200 per day (₹100 CGST + ₹100 SGST) applies, capped at the invoice value—though minor or first-time delays are often waived.

6. Should I integrate directly via API or use a GSP for e-Invoicing?

Enterprises with in-house IT and high invoice volumes benefit most from direct API integration. Mid-sized firms often prefer GSPs for their plug-and-play simplicity, managed updates and support.