Glossary
What is an e-invoice (IRN)?
A B2B invoice that has been registered with the government before it reaches the buyer.
Updated
In short
An e-invoice is a B2B invoice reported to the government's Invoice Registration Portal, which returns an IRN and a signed QR code. SimpleERP does not generate IRNs; businesses above the threshold register invoices on the portal.
An e-invoice under GST is a B2B invoice reported to the government's Invoice Registration Portal, which validates it and returns an invoice reference number, the IRN, and a signed QR code to print on the invoice. It is mandatory for businesses whose aggregate turnover crossed ₹5 crore in any year since 2017-18. It does not change what the invoice says, only how it is validated and reported.
E-invoice (IRN): a worked example
Lakshmi Steel Furnitures billed ₹18,42,600 from April to September 2026, so its yearly turnover is well under ₹5 crore and it does not need e-invoices. If its turnover had crossed ₹5 crore in any year since 2017-18, its ₹11,776 invoice to Ravi Stores would need an IRN before it went out, while a cash sale to a walk-in consumer would not.
Who must issue e-invoices?
Businesses whose aggregate turnover exceeded ₹5 crore in any financial year from 2017-18 onwards, for B2B invoices, exports and credit and debit notes. Some sectors, such as banks and insurers, are exempt. Since 1 April 2025, businesses with turnover of ₹10 crore or more must report an invoice within 30 days of its date. The e-invoicing guide has the details.
FAQ
Questions, answered
Do I need e-invoices for sales to consumers?
Sales to consumers do not need e-invoices. E-invoicing covers B2B supplies, exports and notes against them. Sales to unregistered buyers and consumers are outside it, though businesses above a much higher threshold must print a dynamic QR code on B2C invoices.
Once I cross ₹5 crore, can I stop if turnover falls?
E-invoicing does not stop when turnover falls back below ₹5 crore. The test is turnover above the limit in any financial year since 2017-18, so once you cross it you stay covered even if later years are lower. Check the current notification with your CA when you approach the limit.
Is an invoice without an IRN valid if I am above the threshold?
An invoice without an IRN is not valid above the threshold. For a business that must e-invoice, a B2B invoice without an IRN is not a valid tax invoice, so the buyer cannot claim credit on it and penalties can apply. Register it before you send it.
Does an e-invoice fill my GSTR-1?
Partly. Details of registered e-invoices flow into the B2B and note tables of your GSTR-1 automatically. You still review the return, add B2C sales and the HSN summary, and file it yourself.
Related
Keep reading
E-invoicing threshold
Who must issue e-invoices under GST, how the ₹5 crore AATO test works, and what a small business should prepare before it crosses the line.
Read moreTax invoice
The document a GST-registered business issues for a taxable sale, with the mandatory GST fields.
Read moreE-way bill
The electronic document generated before goods above a set value are moved.
Read more
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