What an e-invoice actually is (and is not)
Many shop owners hear "e-invoice" and assume it means any invoice made on a computer — a PDF bill, an emailed invoice, or a printout from billing software. That is not what the GST law means. An e-invoice is a B2B invoice that has been reported to the government's Invoice Registration Portal (IRP) and has received two things in return: an Invoice Reference Number (IRN) and a signed QR code. Only after the IRP issues that IRN is the invoice legally valid for a business covered by the mandate.
So the invoice itself still looks like a normal tax invoice. The difference is invisible plumbing: your invoice data goes to the IRP, the portal validates it, registers it on the GST system, and sends back the IRN and QR code, which must be printed on the invoice you hand to your buyer. A PDF you made yourself, however professional it looks, is not an e-invoice.
The e-invoice limit: who is in scope
The current e-invoicing turnover threshold is ₹5 crore of aggregate annual turnover, and it has been in force since 1 August 2023. As of FY 2026-27 this ₹5 crore limit still applies — no lower threshold has been notified, despite recurring rumours of a ₹1 crore cut. If your aggregate turnover crossed ₹5 crore in any financial year from 2017-18 onwards, the mandate applies to you. It does not matter if your turnover later dropped below ₹5 crore; once you have crossed it in any year, you stay in scope.
Aggregate turnover means the total across all GSTINs under the same PAN — taxable sales, exports and exempt supplies included. So a wholesaler with two branch registrations adds both together. And the mandate covers B2B invoices, exports, credit notes, debit notes and supplies to government entities. It does not cover B2C retail bills — the invoice you give a walk-in customer without a GSTIN needs no IRN.
A few sectors are exempt regardless of turnover, including banks and insurers, goods transport agencies, passenger transport services and cinema admission. For a typical kirana, garment shop, electronics dealer or FMCG wholesaler, though, the only question that matters is: has my aggregate turnover ever crossed ₹5 crore since 2017-18?
What happens if you skip e-invoicing
If you are covered by the mandate and issue a B2B invoice without an IRN, the law treats that invoice as not issued at all. That has three painful consequences. First, you can face a penalty under Section 122 of the CGST Act — up to ₹10,000 per invoice or 100% of the tax due, whichever is higher, for non-issuance, and up to ₹25,000 for an incorrect invoice.
Second, and often more damaging commercially, your buyer's input tax credit is at risk. GST officers can question ITC claimed against invoices that should have carried an IRN but did not. Once a distributor or corporate buyer discovers your invoices put their credit in danger, they will simply buy from someone compliant. Third, goods moving without a valid invoice can be detained in transit, since e-way bill and e-invoice data are linked on the government systems.
One more deadline worth knowing: since 1 April 2025, businesses with aggregate turnover of ₹10 crore or more must report invoices to the IRP within 30 days of the invoice date. Miss that window and the portal rejects the invoice outright.
How the e-invoice flow works in practice
The good news is that day-to-day, e-invoicing is far less scary than it sounds — if your billing software handles it. The practical flow is: you create the invoice in your billing software as usual; the software sends the invoice data to the IRP in the prescribed format; the IRP validates it and returns the IRN and signed QR code within seconds; your software prints both on the final invoice. Your customer sees a normal invoice with a QR code in the corner.
You can also generate IRNs manually on the government portal by keying in or uploading invoice data, but for a business raising dozens of B2B invoices a day, manual generation is slow and error-prone. Integrated software removes the extra step entirely — billing and IRN generation happen in one action, and the same data can flow into your GSTR-1, cutting down return-filing mismatches.
Common myths, cleared up
Myth one: "Every retailer must do e-invoicing now." False. If your aggregate turnover has never crossed ₹5 crore in any year since 2017-18, e-invoicing simply does not apply to you. You issue normal tax invoices as before.
Myth two: "E-invoicing applies to my counter sales." False. B2C invoices are outside the e-invoice mandate entirely. The only B2C-related rule is the dynamic QR code requirement for customer payments, and that applies only to businesses with turnover above ₹500 crore — nowhere near a typical retail or wholesale operation.
Myth three: "I invoice through my accountant, so this is his problem." The legal liability for issuing a valid invoice sits with the seller — you. If invoices go out without IRNs, the penalties and the angry buyers land at your counter, not your accountant's.
How to get ready before you cross the threshold
If your turnover is approaching ₹5 crore, prepare before the financial year in which you cross it, not after. Start by checking your aggregate turnover for every year since 2017-18 across all GSTINs on your PAN — many owners are surprised to find they crossed the line in an earlier good year. Next, register on the e-invoice portal once you are in scope, and clean up your masters: buyer GSTINs, HSN codes and unit measures must be accurate, because the IRP rejects invoices with bad data.
Most importantly, make sure your billing software can talk to the IRP so that IRN and QR generation happens automatically at the time of billing. If you are evaluating software, ask the vendor directly whether e-invoicing is built in — RetailDek, for example, is e-invoice ready on its Gold plan, so the same system that prints your retail bills can generate IRNs the day the mandate applies to you.
E-invoicing rewards businesses that prepare early. Cross the threshold with your data clean and your software ready, and the transition is a non-event; cross it unprepared, and every B2B sale becomes a compliance risk. Know your number, watch the ₹5 crore line, and set up before you need to.