E-invoicing in GST: who needs it and how it works

An e-invoice is not a new kind of invoice. You still make your GST invoice in your own software. The difference is that, before it is valid, you report it to a government-authorised Invoice Registration Portal (IRP), which checks it, signs it and gives back an Invoice Reference Number (IRN) and a QR code. Those two go on the invoice you hand to your customer.

E-invoicing started in October 2020 for the largest businesses and has been extended in steps. Since 1 August 2023 it reaches many growing small businesses too. This guide explains who is covered, how it works day to day, and the time limits that catch people out.

Who must issue e-invoices

Under Rule 48(4) of the CGST Rules and Notification 13/2020–Central Tax (as amended), e-invoicing applies to a registered person whose aggregate turnover in any preceding financial year from 2017-18 onwards exceeds the notified limit. The limit has come down in steps:

From	Turnover limit (exceeds)	Notification
1 Oct 2020	₹500 crore	13/2020–Central Tax, as amended
1 Jan 2021	₹100 crore	88/2020–Central Tax
1 Apr 2021	₹50 crore	5/2021–Central Tax
1 Apr 2022	₹20 crore	1/2022–Central Tax
1 Oct 2022	₹10 crore	17/2022–Central Tax
1 Aug 2023	₹5 crore	10/2023–Central Tax

As of this guide’s date, ₹5 crore is the current limit; no lower limit has been notified. Three details matter:

• Aggregate turnover is counted across all GSTINs on your PAN, in every state, not per branch.
• Any preceding year means that once you cross ₹5 crore in one financial year, you are covered from the next one, and you stay covered even if turnover later falls.
• It is the turnover test that decides, not the size of a single invoice.

Who is exempt

The notification leaves out these businesses, whatever their turnover:

• Special Economic Zone (SEZ) units
• insurance companies, banking companies and financial institutions, including NBFCs
• goods transport agencies (GTAs)
• suppliers of passenger transport services
• suppliers of admission to cinema (multiplex) screenings
• government departments and local authorities (added by Notification 23/2021–Central Tax)

Which documents are covered

Covered	Not covered
Tax invoices to registered buyers (B2B)	Invoices to consumers (B2C)
Credit notes and debit notes on those	Bills of supply (composition or exempt sales)
Exports (with or without payment of tax)	Delivery challans
Supplies to SEZ units and developers	Imports
Deemed exports

For B2C invoices, only very large businesses have a separate duty to print a dynamic QR code; that is not the same as an e-invoice.

How it works, step by step

1. Make the invoice in your billing or accounting software as usual.
2. Create the e-invoice data in the government’s standard format (a JSON file following the e-invoice schema).
3. Report it to an IRP. The NIC portal (einvoice1.gst.gov.in) is one; GSTN has authorised several others. You can upload through the portal, through a GST Suvidha Provider (GSP), or directly through an API.
4. The IRP validates it, checks for duplicates, and generates the IRN, a unique 64-character reference.
5. You receive the signed invoice data and a signed QR code. Print the IRN and QR code on the invoice and share it with your customer.
6. The details flow onward. The IRP shares them with the GST system, so they are filled into your GSTR-1 (and reach your buyer’s GSTR-2B once you file it), and can be used to create an e-way bill.

Rule 48(5) is the reason this matters: an invoice that a covered business issues without following this process is not treated as a valid invoice, and your buyer cannot rely on it for input tax credit.

The 30-day reporting limit

A GSTN advisory of 5 November 2024 set a time limit for larger businesses:

• Who: taxpayers with aggregate annual turnover (AATO) of ₹10 crore or more.
• From: 1 April 2025.
• Rule: invoices, credit notes and debit notes older than 30 days from the date of reporting cannot be reported. The IRP refuses to generate an IRN.
• Below ₹10 crore: GSTN says there is no such restriction “as of now”.

A late invoice cannot be fixed later, so build reporting into the billing process instead of doing it in a monthly batch.

Cancelling or correcting an e-invoice

• An IRN can be cancelled on the IRP within 24 hours of generation, in full only; partial cancellation is not possible.
• After 24 hours, correct the sale with a credit note or debit note, which also needs its own IRN if you are covered.
• Once cancelled, the same invoice number cannot be used again for a fresh IRN.

Worked example

Meera Distributors in Jaipur has two GSTINs on one PAN: Rajasthan and Gujarat.

Financial year	Rajasthan GSTIN	Gujarat GSTIN	Aggregate turnover
2024-25	₹3.6 crore	₹0.9 crore	₹4.5 crore
2025-26	₹4.1 crore	₹1.3 crore	₹5.4 crore

Neither GSTIN crosses ₹5 crore alone, but the PAN-level total does in 2025-26. So both GSTINs must issue e-invoices for B2B sales from 1 April 2026. Their turnover is below ₹10 crore, so the 30-day limit does not apply to them yet; if they reach ₹10 crore, an invoice dated 3 October would have to be reported by 2 November.

Getting ready: a checklist

If your turnover is close to ₹5 crore, prepare before the new financial year starts rather than on 1 April.

1. Check your PAN-level turnover for each year since 2017-18. Your accountant or the GSTR-9 annual returns will show it.
2. Clean your customer master. The IRP rejects invoices with an invalid buyer GSTIN, a wrong state code or a missing pincode, so verify each business customer once.
3. Check HSN codes. At ₹5 crore and above you need at least 6 digits on every invoice, and the IRP validates the code.
4. Decide how you will report: manually on the IRP, through a GSP, or from billing software that prepares the data for you.
5. Make it part of billing, not month-end work: the invoice is not valid until it has an IRN, and at ₹10 crore and above the 30-day clock is running.
6. Train whoever cancels invoices that the IRP window is 24 hours.

What may change next

At its 57th meeting on 8 October 2026, the GST Council recommended extending e-invoicing, for businesses with turnover of ₹5 crore and above, to supplies received from unregistered persons on which the buyer pays tax under reverse charge, and to imports of services. This is a recommendation; it applies only from the date a notification says. Watch the CBIC and GST portal announcements.

Doing it in your billing software

You can report e-invoices by hand on the IRP, but it is slow for more than a few invoices a day. Invoiqo’s Business and Pro plans include e-invoicing: Invoiqo prepares each B2B invoice in the IRP’s JSON format, records the IRN and signed QR code on the invoice, and locks the invoice against edits once it has an active IRN, so the printed copy always matches what the government holds. For the fields an invoice needs in the first place, see GST invoice rules: mandatory fields.

In short

If your PAN’s turnover crossed ₹5 crore in any year since 2017-18, report every B2B invoice, credit note and debit note to an IRP and print the IRN and QR code. At ₹10 crore and above, do it within 30 days. Cancel within 24 hours or use a credit note. To see which plan includes e-invoicing, compare Invoiqo’s plans.