E-invoicing means your B2B invoices are reported to a government Invoice Registration Portal (IRP) and come back with a unique number and a QR code. Without them, the invoice isn't valid under GST. Here's what applies in 2026, and what your billing software needs to handle it without extra work.
Who has to generate e-invoices
Any business whose aggregate annual turnover (AATO) has crossed ₹5 crore in any financial year from 2017–18 onwards. The limit is counted across all GST registrations under the same PAN, not per GSTIN. Once you cross it in any year, it applies from then on, even if turnover later falls.
Documents covered
- Tax invoices for B2B supplies
- Exports
- Credit notes and debit notes
Commonly exempt
- SEZ units
- Banks, insurance companies and NBFCs
- Goods transport agencies
- Passenger transport services
- Cinema admission services (multiplexes)
Sales to consumers (B2C) don't need an e-invoice. Very large businesses, above ₹500 crore turnover, must print a dynamic QR code on B2C invoices instead.
The 30-day reporting rule
Since 1 April 2025, businesses with AATO of ₹10 crore or more must report each invoice, credit note and debit note to the IRP within 30 days of its date. After 30 days the portal won't accept it, so you can't get an IRN, and the document isn't valid.
In practice this catches invoices raised in a hurry and reported "later", and credit notes issued at quarter-end for old invoices.
What happens when you report an invoice
- Your software sends the invoice details to the IRP in the standard format.
- The IRP checks it and returns an Invoice Reference Number (IRN), a signed invoice and a QR code.
- The QR code is printed on the invoice you send to your customer.
- The details flow to the GST system, which helps pre-fill your GSTR-1.
- If goods are moving, an e-way bill can be generated from the same data.
An e-invoice can be cancelled on the portal within 24 hours of generation. After that, you correct it with a credit note.
The cost of getting it wrong
An invoice without a valid IRN is treated as not issued. Your customer may not be able to claim input tax credit on it, which damages the relationship fast. Penalties for not issuing a valid invoice can reach the tax amount involved, with a minimum of ₹10,000.
What your billing software must do
Feature | Why it matters |
|---|---|
Direct IRP connection | IRN and QR come back in seconds, with no upload and download of files. |
Checks before sending | Catches wrong GSTINs, HSN codes and tax rates before the IRP rejects them. |
30-day alerts | Flags invoices and credit notes that are close to the reporting limit. |
Credit and debit notes | Reports them the same way as invoices, linked to the original. |
E-way bill from the invoice | One entry for both, so vehicle and distance aren't typed twice. |
Cancellation inside 24 hours | Cancels on the IRP and in your books together. |
Branch and GSTIN handling | Uses the right registration for every branch automatically. |
Error log | Shows which invoices failed and why, so they're fixed the same day. |
A quick self-check
- Do you know your AATO across all GSTINs for each year since 2017–18?
- Does anyone download JSON files and upload them by hand?
- Are credit notes ever raised more than 30 days after the invoice?
- Is the e-way bill entered separately from the invoice?
- Can you see today's failed or pending e-invoices on one screen?
If any answer worries you, the fix is usually in how billing is connected, not in more manual checks.