GST e-invoicing explained

Updated 11 October 2026

E-invoicing means reporting each business-to-business (B2B) invoice to a government Invoice Registration Portal (IRP), which validates it and returns a unique Invoice Reference Number (IRN) and a signed QR code. It is compulsory for businesses whose aggregate turnover exceeded ₹5 crore in any financial year from 2017-18 onwards. An invoice that should have been registered but was not is not treated as a valid invoice.

Who must use e-invoicing

E-invoicing was phased in, starting with the largest businesses. The threshold has stayed at ₹5 crore since 1 August 2023:

The test looks at aggregate turnover for the whole PAN, across all states, in any previous financial year since 2017-18. Once you cross ₹5 crore in one year, e-invoicing applies from then on, even if your turnover later falls.

Which documents are covered

• Tax invoices for B2B supplies, including supplies to SEZs and deemed exports
• Export invoices
• Credit notes and debit notes on these supplies
• Supplies under reverse charge where the supplier is liable to issue the invoice

Sales to consumers (B2C) are not e-invoiced. Very large businesses, with turnover above ₹500 crore, must instead print a dynamic QR code on B2C invoices so customers can pay digitally.

How e-invoicing works

1. You prepare the invoice in your billing or accounting software in the standard e-invoice format.
2. The software (or you, through the portal) uploads it to an IRP. The government-run portal and several private IRPs are available.
3. The IRP checks it for duplicates and errors, generates the IRN (a unique 64-character code), digitally signs the invoice and adds a QR code.
4. You print the QR code on the invoice and send it to the buyer.
5. The data flows automatically into your GSTR-1 and, where needed, Part A of the e-way bill.

It is still your own invoice. E-invoicing does not mean the government creates invoices for you; it means they are registered before being issued.

Who is exempt

These businesses do not need to e-invoice, whatever their turnover:

• SEZ units (but not SEZ developers)
• Insurance companies, banking companies and financial institutions, including NBFCs
• Goods transport agencies
• Suppliers of passenger transport services
• Suppliers of admission to cinema in multiplex screens
• Government departments and local authorities

The 30-day reporting rule

Since 1 April 2025, businesses with aggregate turnover of ₹10 crore or more must report an invoice to the IRP within 30 days of the invoice date. The IRP rejects older invoices, and without an IRN the invoice is not valid. In practice, every e-invoicing business should register invoices on the day they are raised.

What happens if you skip it

• An invoice that needed an IRN but does not have one is not a valid tax invoice.
• The buyer cannot claim input tax credit on it, which damages the business relationship.
• Penalties can apply for issuing invalid invoices.

Cancelling or correcting an e-invoice

An IRN can be cancelled in full on the IRP within 24 hours of generation. Partial cancellation is not allowed. After 24 hours, mistakes are corrected with a credit note or debit note, which is itself e-invoiced. A cancelled invoice number cannot be reused.

Proposed changes

The 57th GST Council meeting on 8 October 2026 recommended extending e-invoicing, for businesses with turnover of ₹5 crore or more, to reverse charge purchases from unregistered persons and to imports of services. This applies only after it is notified. For the latest rules, see gst.gov.in and cbic-gst.gov.in.

Use our GST calculator to check the tax on each invoice line.