If your business crossed ₹5 crore turnover even once, in any year since 2017-18 you are required to generate e-invoices for every B2B sale. Right now. Not from next month, not from next year. Today.

And if you're still raising regular invoices without an IRN and QR code, every single one of those invoices is legally invalid under GST law. Your buyers cannot claim ITC on them. And you face a penalty of ₹10,000 per invoice or 100% of the tax amount, whichever is higher.

This guide is written by Chartered Accountants who work with Indian SMEs daily. We've covered everything Tally's article doesn't the penalty structure in full, the SEZ developer vs SEZ unit distinction that confuses hundreds of businesses, the multi-GSTIN trap, the 30-day rule, what to do after you miss the cancellation window, and how to check right now whether you're already in the e-invoicing net.

What is E-Invoicing? (The Common Misconception Cleared First)

Most business owners hear "e-invoicing" and think it means creating invoices on a government website. That is not what it means.

E-invoicing under GST is a system where:

1. You create your invoice in your own billing software (just as you always have)

2. Your software sends that invoice data to the Invoice Registration Portal (IRP) — a government-authorised portal

3. The IRP validates the data, assigns a unique Invoice Reference Number (IRN), digitally signs the invoice, and attaches a QR code

4. Your software receives the signed invoice back typically within seconds

5. You share the invoice with the IRN and QR code printed on it with your buyer

The invoice your buyer receives looks almost identical to your old invoice just with an IRN number and a scannable QR code added. That QR code is not decorative. It contains digitally signed invoice data that buyers, auditors, and GST officers can verify using the GSTN's official QR Code Verifier app.

The key point: An invoice issued by an eligible business without a valid IRN is not an invoice in the eyes of GST law. It is a piece of paper.

Who Must Generate E-Invoices in 2026?

The turnover threshold ₹5 crore

<cite index="25-1">E-invoicing is mandatory for all businesses whose Aggregate Annual Turnover (AATO) exceeded ₹5 crore in any financial year from FY 2017-18 onwards.</cite>

Read that carefully. It is not about your current year turnover. If you crossed ₹5 crore in FY 2021-22 and have since come down to ₹3 crore, you are still covered. The threshold is a one-way gate once crossed, you're in.

The multi-GSTIN trap many businesses miss

<cite index="26-1">If your business has operations in multiple states say, Maharashtra, Rajasthan, and Gujarat with separate GSTINs for each, the turnover of all three is added together at the PAN level.</cite>

This is how businesses unknowingly fall into the e-invoicing net. A business owner with three state registrations, each with ₹2 crore turnover, has a combined AATO of ₹6 crore and is fully covered under e-invoicing, even though no individual GSTIN crossed ₹5 crore.

How to check right now: Log in to the e-invoice portal (einvoice1.gst.gov.in) and use the "Check Enablement Status" tool with your GSTIN. If the system has flagged you for mandatory compliance, you are covered regardless of what you believe your turnover to be.

What types of transactions require e-invoicing?

E-invoicing applies to:

• B2B invoices — sales to registered GST taxpayers

• B2G invoices — supplies to government departments and entities (even if unregistered)

• Export invoices — goods and services exported outside India (with or without IGST)

• Deemed exports — supplies to EOU, EPCG licence holders, etc.

• Credit notes and debit notes — amendments to the above categories also require IRP reporting

• Advance receipts (where applicable) — for services with advance payments

What does NOT require e-invoicing?

• B2C invoices — sales to individual consumers (though a Dynamic QR Code is mandatory on B2C invoices if your turnover exceeds ₹500 crore)

• Supplies between different GSTINs of the same PAN (between your own branches)

Who is Exempt from E-Invoicing? (The Full List for 2026)

Even if your turnover exceeds ₹5 crore, certain sectors are permanently exempt from e-invoicing under CBIC Notification No. 13/2020-Central Tax (as amended):

The SEZ distinction that trips up many businesses

This is a nuance most articles — including Tally's gloss over.

<cite index="23-1">SEZ units (businesses operating within a Special Economic Zone) are exempt from generating e-invoices. However, SEZ developers (entities that develop and maintain SEZs) must comply with e-invoicing if their turnover exceeds the threshold. This distinction has caused confusion and non-compliance.</cite>

If you are an SEZ developer building, maintaining, or managing a Special Economic Zone you are not exempt, even though your address may be inside an SEZ. Only SEZ units (businesses operating within the zone to produce goods or services) are exempt.

Pro tip from our CA team: If you are unsure whether your business qualifies for an exemption, use the "E-invoice Exemption Declaration" tool on the GST portal. Filing this declaration proactively prevents automated system notices when the GSTN's AI-driven compliance checks scan your filing patterns.

The 30-Day Reporting Rule — Who It Applies to and What It Means

<cite index="24-1">Starting 1 April 2025, businesses with an AATO of ₹10 crore or more must upload their invoices to the IRP within 30 days of issuance.</cite>

What this means in practice: If you issue an invoice dated 1st June, the IRP will reject any upload attempt after 30th June. The portal will not generate an IRN for that invoice. It becomes permanently invalid for the purpose of ITC claims.

Who does the 30-day rule apply to?

• Businesses with AATO of ₹10 crore and above: Yes, strictly enforced

• Businesses between ₹5 crore and ₹10 crore: Not currently mandated, but strongly recommended as best practice

The hidden risk for businesses between ₹5–10 crore: The government has consistently lowered the threshold for new compliance obligations. The 30-day rule started at ₹100 crore businesses, then came down to ₹10 crore. It is widely expected to extend to ₹5 crore businesses. Businesses that develop the habit of real-time e-invoice generation now will not need to change their process when the rule extends.

Mandatory Two-Factor Authentication (2FA) on the E-Invoice Portal

Since 2025, all IRP portal logins require 2FA a username/password plus an OTP sent to your registered mobile number.

The practical challenge this creates for manual filers: If you or your accountant logs into the portal manually to upload invoices, you need your registered mobile phone available every time. This slows down bulk invoice generation.

How integrated software solves this: With hisabkitab's IRP integration, you authenticate once per session. The software then handles all IRP communication in the background for every invoice you create you never need to manually interact with the portal again during that session.

The Penalty for Non-Compliance In Full Detail

This is the section most articles understate. Here are the exact penalties under CGST Rules:

Penalty for not generating an e-invoice at all

<cite index="23-1">An invoice issued without IRN by an e-invoicing-applicable taxpayer is considered invalid under GST law. The buyer cannot claim Input Tax Credit (ITC) on such an invoice. Additionally, the supplier may be penalized under Section 122 of the CGST Act, which imposes a penalty of ₹10,000 or 100% of the tax due, whichever is higher.</cite>

Example: You issue a B2B invoice for ₹2,00,000 with 18% GST = ₹36,000 tax. Without a valid IRN, the penalty is either ₹10,000 or ₹36,000 (100% of tax) whichever is higher. In this case: ₹36,000 penalty per invoice.

If you issue 50 such invoices in a month: ₹18,00,000 in potential penalties.

Penalty for incorrect e-invoice details

<cite index="29-1">The penalty for an incorrect or erroneous e-invoice is ₹25,000 per invoice.</cite>

Penalty for violating the 30-day reporting window

<cite index="28-1">Failing to report an invoice within 30 days of generation leads to rejection by the IRP, regulatory penalties, and fines. The invoice carries no QR code and cannot be used to support an ITC claim by the buyer.</cite>

Additional consequences beyond the penalty

• Your buyer loses ITC on that invoice — which damages your business relationship and can delay payments

• <cite index="28-1">Your clients will see a "flag" in their Invoice Management System (IMS)</cite> — a visible compliance red mark against your business

• The goods may be detained in transit if e-way bill is linked to an invalid invoice

• <cite index="32-1">Legal archiving is required for 6 years</cite> — invalid invoices create gaps in your records

• <cite index="23-1">Repeated non-compliance can also trigger GST audits</cite>

The E-Invoicing Journey — From Invoice to IRN (Step by Step)

Here is exactly what happens when a compliant e-invoice is generated:

Step 1 — Invoice creation You create a sales invoice in your billing software with all required fields: supplier GSTIN, buyer GSTIN, invoice number and date, item details, HSN/SAC code (minimum 4 digits for ₹5–10 crore turnover; minimum 6 digits for above ₹10 crore), tax rates, and total value.

Step 2 — JSON generation Your software converts the invoice data into a JSON file conforming to the GSTN schema (Version 1.1 as of 2026).

Step 3 — Upload to IRP The JSON is uploaded to one of the authorised IRPs: NIC (einvoice1.gst.gov.in), ClearTax, IRIS, Cygnet, or others. Your software does this automatically if IRP-integrated.

Step 4 — IRP validation The IRP checks: Is the supplier GSTIN active? Is the buyer GSTIN active? Is it a duplicate invoice number? Are the mandatory fields complete?

Step 5 — IRN generation If valid, the IRP generates a unique 64-character IRN (hash of GSTIN + financial year + invoice number), digitally signs the invoice, attaches a QR code, and returns it typically within 2–3 seconds.

Step 6 — Invoice delivery Your software embeds the IRN and QR code on the invoice and you send it to your buyer. The data is simultaneously pushed to the GST portal for auto-population of GSTR-1.

What Happens If You Need to Cancel or Amend an E-Invoice?

Cancellation — within 24 hours

<cite index="22-1">An e-invoice can be cancelled within 24 hours of generation on the IRP. If you miss this window, you cannot cancel the IRN.</cite>

This 24-hour window is strict. If you discover an error — wrong buyer GSTIN, wrong amount, wrong HSN after 24 hours, cancellation on the IRP is no longer possible.

What to do after the 24-hour cancellation window

<cite index="22-1">If you miss the cancellation window, you cannot cancel the IRN. You must issue a Credit Note to nullify the transaction and report that Credit Note to the IRP.</cite>

Credit notes issued against e-invoices must also be reported to the IRP and will receive their own IRN. This is a point many businesses miss credit notes are not exempt from e-invoice reporting just because the original invoice had one.

Important: You can mark an e-invoice as cancelled in your own accounting software, but that does not cancel it on the GST portal. Only IRP cancellation (within 24 hours) or a reported Credit Note achieves legal nullification.

The Gradual Rollout — How We Got to ₹5 Crore

Understanding the history helps you appreciate how quickly the threshold has dropped — and where it may be heading:

<cite index="22-1">While there have been discussions and proposals to lower the limit to ₹3 crore or even ₹2 crore, as of 2026, the mandatory threshold remains ₹5 crore. Always check official CBIC notifications for the latest updates.</cite>

The direction is clear. Every 6–18 months, the threshold has dropped. Businesses currently below ₹5 crore would be wise to prepare now — integrating e-invoicing capability before the mandate arrives is far less disruptive than scrambling to comply after a notification.

Real-World Example What Non-Compliance Actually Looks Like

Vikram runs a pharmaceutical distribution company in Pune. His turnover in FY 2022-23 was ₹6.2 crore. In FY 2024-25 it dropped to ₹4.1 crore.

He assumed that since his current year turnover was below ₹5 crore, he no longer needed to generate e-invoices. He continued raising regular invoices for 4 months of FY 2025-26.

His largest buyer a hospital chain noticed that Vikram's invoices had no IRN or QR code. Their IMS dashboard flagged the invoices. The hospital's GST team could not claim ITC on ₹8,40,000 worth of purchases. They held back payment of the GST portion ₹1,51,200 pending resolution.

The relationship of 4 years was severely strained. Vikram then had to retroactively register on the IRP, generate fresh invoices for past supplies (which triggered amendment complications in GSTR-1), and pay interest on delayed ITC corrections his buyer had to make.

The error: not understanding that the ₹5 crore threshold is based on any year since 2017-18, not just the current year.

Benefits of E-Invoicing Beyond Just Compliance

Most coverage focuses on obligations and penalties. But there are genuine operational benefits to e-invoicing that the Tally article barely touches on:

GSTR-1 is auto-populated: Every e-invoice you generate is pushed directly to the GST portal. Your GSTR-1 is pre-filled from your IRN data — eliminating manual data entry and the mismatches that create DRC-01B notices.

Faster payments from large buyers: Corporates and government entities trust IRN-verified invoices. Many now have internal processes that fast-track payment for invoices with valid QR codes.

Access to invoice discounting and financing: <cite index="31-1">Hassle-free access to formal credit channels, such as invoice discounting or invoice financing, provides leverage to small businesses since their invoices are validated and authentic.</cite> Banks and NBFCs are more willing to advance funds against IRN-verified invoices.

Reduced audit risk: Every e-invoice is immutably registered on government servers. If your books are questioned, the IRN trail provides instant, tamper-proof verification of every transaction.

E-way bill integration: For goods requiring e-way bills, the IRP data auto-populates the e-way bill portal reducing duplicate data entry and the risk of vehicle detention for documentation mismatches.

How hisabkitab Handles E-Invoicing Built for Indian SMEs

hisabkitab is IRP-integrated and built by Chartered Accountants who understand exactly how e-invoicing fits into a small business's daily billing workflow.

Here's what happens when you create an invoice in hisabkitab:

Real-time IRP submission: The moment you save a B2B invoice, hisabkitab sends the data to the IRP automatically. The IRN and QR code are returned and embedded into your invoice typically within 3–5 seconds. You don't leave the invoice screen.

Automatic eligibility check: hisabkitab monitors your rolling turnover and alerts you when you approach the ₹5 crore threshold before you cross it and before you risk raising a non-compliant invoice.

30-day deadline tracking: For businesses above ₹10 crore, hisabkitab flags invoices approaching the 30-day IRP upload deadline with clear alerts so no invoice ever gets rejected by the portal due to timing.

6-digit HSN enforcement: For businesses above ₹10 crore turnover, hisabkitab automatically enforces 6-digit HSN codes at the invoice level preventing the most common cause of e-invoice validation errors.

Credit note IRP reporting: When you issue a credit note against an e-invoice, hisabkitab automatically reports it to the IRP and generates a credit note IRN ensuring your credit notes are as legally valid as your original invoices.

Cancellation window reminder: If you need to amend an invoice, hisabkitab shows a clear 24-hour countdown on every e-invoice from the time of generation so you never accidentally miss the cancellation window.

Try hisabkitab free for 7 days no credit card required: hisabkitab.co Built by CAs. Trusted by 10,000+ Indian businesses.

E-Invoicing Compliance Checklist for Indian SMEs (June 2026)

Use this before your next invoice cycle:

• Calculate your AATO across all GSTINs under your PAN for every year since FY 2017-18

• If any year exceeded ₹5 crore register on the IRP at einvoice1.gst.gov.in immediately

• Use the "Check Enablement Status" tool on the IRP portal to verify your compliance status

• If you are in an exempt sector (banking, GTA, transport, multiplex, SEZ unit) file the "E-invoice Exemption Declaration" on the GST portal

• If you are an SEZ developer (not an SEZ unit) confirm you are generating e-invoices

• If your AATO is above ₹10 crore review the 30-day upload window and ensure no pending invoices are at risk

• Confirm your billing software is IRP-integrated (not requiring manual portal upload)

• Check that your invoices carry HSN codes of at least 4 digits (6 digits if above ₹10 crore)

• Review your credit note process credit notes against e-invoices also need IRP reporting

• Reset your invoice series at the start of every financial year (April 1)

  
  The Bottom Line

  E-invoicing in India in 2026 is not optional for businesses above ₹5 crore in aggregate annual turnover in any year since 2017-18. Every B2B invoice without a valid IRN is legally invalid. The penalties are severe: ₹10,000 or 100% of tax per invoice for non-generation, and ₹25,000 for incorrect invoices.
  
  

  But beyond compliance, e-invoicing brings real business benefits GSTR-1 auto-population, faster payments from large buyers, access to invoice financing, and a tamper-proof audit trail.
  
  

  The difference between a compliant business and a non-compliant one in 2026 often comes down to one thing: whether your billing software is IRP-integrated or not. If you're still uploading to the portal manually or worse, raising invoices without IRN altogether the window to fix this cleanly is now.
  
  

  Start your 7-day free trial at hisabkitab.co IRP-integrated e-invoicing, GST returns, and AI accounting built by CAs for Indian businesses.