IFF explained: monthly B2B invoice upload for quarterly filers

Who can use IFF

Only registered persons who have opted for the Quarterly Return Monthly Payment (QRMP) scheme can use IFF. It is provided under the proviso to Rule 59(2) of the CGST Rules. Monthly GSTR-1 filers do not need it because their invoices reach buyers every month anyway.

What goes into IFF

• B2B invoices, including supplies on which the buyer pays tax under reverse charge
• Credit notes and debit notes issued to registered persons
• Amendments to B2B invoices and notes uploaded earlier
• Total value of invoices in IFF limited to Rs. 50 lakh for each month; anything beyond goes in the quarterly GSTR-1
• No B2C, export summary, HSN summary or nil-rated details, which belong in the quarterly GSTR-1

Timing and effect

IFF for month one of a quarter can be filed from the 1st to the 13th of month two, and IFF for month two from the 1st to the 13th of month three. There is no IFF for the third month; those invoices go into the quarterly GSTR-1 due by the 13th after the quarter.

Invoices uploaded through IFF reach the buyer's GSTR-2B for that month. They are not repeated in the quarterly GSTR-1, which only covers the remaining invoices. Since IFF is optional, no late fee is charged for not using it, but once the 13th passes the window for that month closes and the invoices move to the quarterly return.

Should you use it

If your customers are registered businesses that file monthly, they will usually insist on IFF, because without it their credit on your invoices is delayed by up to two months. Some buyers delay payment until the invoice appears in their GSTR-2B. If you mostly sell to consumers, IFF adds little.

Keep the same discipline as GSTR-1: correct GSTINs, invoice numbers and place of supply. Also make sure Rule 10A bank details are on record, since their absence blocks IFF as well as GSTR-1.

Get it handled for you

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This guide explains the law in general terms as of October 2026. Time limits and requirements can depend on the facts of your case and on the notice you received.