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About this tool
Late fee and section 50 interest on delayed GSTR-1, GSTR-3B and GSTR-9 filing, with the turnover-linked late fee caps applied.
The GST Late Fee and Interest Calculator works out what a late GST return actually costs: the per-day late fee for GSTR-1, GSTR-3B or GSTR-9 up to the turnover-linked cap, plus interest under section 50(1) of the CGST Act at 18% a year on the tax you paid late in cash. It counts the whole days between the due date and the actual filing date, applies the combined CGST + SGST rate, and stops the fee at the cap for your turnover slab. It is meant for taxpayers and accountants reconciling a delayed filing before they pay.
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Pick GSTR-3B, GSTR-1 or GSTR-9 under Return, set the Due date and Actual filing date, and tick "This is a nil return" if no tax was payable.
Choose the Turnover slab that sets the late fee cap — or enter Annual turnover (INR) for GSTR-9 — plus the Tax paid late, in cash (INR) for GSTR-3B interest.
Read the Total payable split into the capped late fee and Interest @ 18% p.a., then press Copy summary for the day count and breakdown.
Shows the uncapped fee alongside the capped one, so you can see exactly when the ceiling took over.
GSTR-1 and GSTR-9 carry no tax payment, so section 50 interest is correctly left out of those two.
Interest is computed on the tax you settled in cash, since credit set off against the liability does not attract it.
For a regular GSTR-3B or GSTR-1 it is ₹50 per day combined — ₹25 under CGST and ₹25 under SGST. A nil return is charged ₹20 per day combined and is capped at ₹500. GSTR-9 is different: it runs at 0.04% of annual turnover per day.
It depends on the return and your turnover. GSTR-3B caps at ₹5,000 for turnover up to ₹1.5 crore and ₹10,000 above that; GSTR-1 caps at ₹2,000, ₹5,000 and ₹10,000 across the up-to-₹1.5-crore, ₹1.5–5-crore and above-₹5-crore slabs; GSTR-9 caps at 0.50% of annual turnover.
18% a year under section 50(1) of the CGST Act, charged for the number of days the tax stayed unpaid. The calculator applies it as tax × 18% × days ÷ 365, on the cash portion of the liability only — tax discharged from input tax credit does not attract it.
No. The result reflects the standard statutory rates and caps only; conditional waivers and amnesty schemes announced by notification are not applied. Check the notification in force for your tax period, and confirm with your tax adviser before paying — this is informational, not tax advice.
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