Free tool · GST

GST Interest Calculator

Work out the interest on GST paid after the due date — 18% per annum on tax paid late, or 24% on excess ITC claimed — for any number of delay days.

Interest payable
₹739.73
Per day
₹24.66
Tax + interest
₹50,739.73

Interest = tax × rate% × days ÷ 365. Indicative — confirm on the GST portal.

Frequently asked questions

What is the GST interest rate?

18% per annum on tax paid after the due date, and 24% per annum on input tax credit claimed in excess or output liability reduced wrongly.

How is it computed?

Interest = tax × rate% × days of delay ÷ 365. The tool also shows the per-day interest and the tax-plus-interest total.

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