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GST Interest Calculator (Section 50)
Section 50 of the CGST Act charges interest on GST paid late. The standard rate is 18% per annum on the delayed tax (Section 50(1)), and a higher 24% per annum applies where input tax credit has been wrongly availed and utilised (Section 50(3)). Interest is computed on the net cash liability — the amount actually payable through the electronic cash ledger, not the portion set off by legitimate ITC — and runs from the day after the due date to the date of payment. The formula is interest = tax × rate × days / 365. On ₹50,000 of tax paid 30 days late at 18%: 50,000 × 0.18 × 30 / 365 = ₹739.73 ≈ ₹740. Enter your tax, due date and payment date to compute the exact interest payable. Free, no login.
Section 50(1): 18% per annum on delayed GST (the standard late-payment rate)
- Section 50(3): 24% per annum where ITC was wrongly availed AND utilised
- Formula: interest = tax × rate_pa × days / 365
- Day count: from the day after the due date up to (and including) the date of payment
- Charged on the NET CASH liability — not on the portion legitimately set off by ITC
- Worked example — ₹50,000 tax, 30 days late @ 18%: 50,000 × 0.18 × 30/365 = ₹739.73 ≈ ₹740
- Worked example — ₹1,00,000 tax, 45 days late @ 18%: 1,00,000 × 0.18 × 45/365 = ₹2,219.18
- From Jan-2026 the GST portal nets the minimum electronic-cash-ledger balance before charging interest
Frequently asked questions
What is the interest rate on late GST payment?
Under Section 50(1) of the CGST Act, interest on delayed GST is 18% per annum. A higher 24% per annum applies under Section 50(3) only where input tax credit has been wrongly availed and utilised. The interest is calculated as tax × rate × days / 365, where the days are counted from the day after the due date to the date of actual payment. For example, ₹50,000 paid 30 days late at 18% attracts 50,000 × 0.18 × 30 / 365 = ₹739.73 (≈ ₹740).
Is GST interest charged on the gross or net liability?
Interest under Section 50 is charged on the net cash liability — the tax that has to be discharged through the electronic cash ledger — not on the gross output tax. The portion of your liability that is legitimately set off using input tax credit does not attract interest. This was clarified by amendment to Section 50 and is the position followed by the GST portal. From January 2026 the portal further nets the minimum electronic-cash-ledger balance available during the delay period before charging interest.
When does the 24% interest rate apply?
The higher 24% per annum rate under Section 50(3) applies only in the specific case where input tax credit has been both wrongly availed and utilised — i.e. you claimed ITC you were not entitled to and used it to reduce your tax. Ordinary late payment of a correctly assessed liability attracts the standard 18% rate under Section 50(1), not 24%. If you are unsure which applies, treat routine late payment as 18% and consult a tax professional for wrongful-ITC situations.