GSTR-3B is the return in which GST is paid. It summarises outward supplies, reverse charge purchases, input tax credit claimed and reversed, and the net tax payable, which is paid from the credit ledger and the cash ledger.
Due dates (as of October 2026)
- Monthly filers
- 20th of the following month.
- Quarterly filers under QRMP
- 22nd or 24th of the month after the quarter, depending on the state, with tax paid monthly in the first two months.
Late fee and interest
The late fee is ₹50 a day (₹25 CGST and ₹25 SGST), or ₹20 a day for a nil return, capped by turnover slab. Interest at 18% a year runs on tax paid late in cash. Interest at 18% also applies to credit wrongly claimed and used.
How it links to other returns
The sales figures are filled in from your GSTR-1, and the credit figures from your GSTR-2B. Differences between GSTR-1, GSTR-3B and GSTR-2B are the most common trigger for a notice, so the three should be reconciled every month before filing.
For a CA firm the 3B date is the busiest of the month: each client's sales, purchases and credit have to be closed in a few days.