GST Interest Calculator
FreeWork out the 18% interest on a late GST payment.
How GST interest is calculated
Under Section 50 of the CGST Act, interest at 18% per annum applies on GST paid after the due date. The formula is simply:
Interest = Tax amount × 18% × (days delayed ÷ 365)
Interest is charged on the net tax discharged in cash for each day of delay, from the day after the due date up to the date of payment. A higher 24% rate can apply to undue input tax credit reversals under Section 50(3) — this tool uses the standard 18% rate.
Frequently asked questions
- What is the GST interest rate for late payment?
- Interest is 18% per annum on the tax paid late, under Section 50 of the CGST Act. A 24% rate applies in specific cases such as excess or undue input tax credit claimed and reversed.
- From which date is GST interest calculated?
- From the day after the return's due date until the date the tax is actually paid. The number of days is multiplied by the daily interest rate (18% ÷ 365).
- Is interest charged on the gross tax or only the cash portion?
- Interest is levied on the net tax liability paid in cash (after setting off available input tax credit) for the period of delay.
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