This GST interest calculator tells you what you owe when GST reaches the government after its due date. Type the tax paid late, the due date and the date you paid (or will pay). It counts the days and applies the yearly rate of 18%, giving the interest due, the interest per day and the total to pay.
Interest on late GST is charged under section 50 of the CGST Act on the part of the tax paid in cash, from the day after the due date until the day of payment. It applies separately to the central, state and integrated parts, but working on the total gives the same overall figure.
At a glance
- Rate18% a year
- Charged onTax paid in cash (net of input tax credit)
- PeriodDay after due date to date of payment
- FormulaTax × rate × days ÷ 365
- Example₹1 lakh paid 43 days late: ₹2,121
- Separate fromLate fee for filing the return late
How the GST interest calculator works
Interest = tax paid late × rate × days late ÷ 365. Days are counted from the day after the due date up to and including the day of payment.
Example: ₹1,00,000 of GST due on the 20th of one month is paid 43 days late. Interest at 18% = 1,00,000 × 18% × 43 ÷ 365 = ₹2,121. That is about ₹49 a day. For ₹2,50,000 paid 74 days late, the interest is ₹9,123. The GST late payment interest calculator above shows these figures as soon as you pick the dates.
What GST interest is charged on
- Net cash liability: interest on late payment is charged on the part of tax paid through the electronic cash ledger, not on the part set off with input tax credit, provided the return is filed.
- Wrongly availed and used credit: if input tax credit was wrongly taken and used, interest also applies at the notified rate, now the same 18%.
- Tax found in an audit or notice: interest runs from the original due date.
The GST portal works out interest for returns filed late and shows it in the return. Compare its figure with this calculator before you pay.
GST interest vs late fee
| Charge | Why | How much |
|---|---|---|
| Interest | Tax paid after the due date | 18% a year on the tax, per day late |
| Late fee | Return filed after the due date | A fixed amount per day, capped, set by notification and lower for nil returns and small taxpayers |
A late return usually brings both: a late fee for the return and interest on the tax. This calculator covers interest only. Check the current late fee on the GST portal.
Interest calculator GST: tips to keep it low
- Pay the tax on time even if the return is delayed, using the challan; interest stops once cash is deposited and set off.
- Keep enough cash in the electronic cash ledger before the due date.
- Reconcile input tax credit monthly so you do not under pay and owe interest later.
- If you discover an under payment, pay it with interest at once rather than waiting for a notice.
GST law and notifications change. This calculator gives a straightforward estimate. For a notice, a dispute or a complex case, consult a chartered accountant or GST practitioner. The law and rules are on the CBIC GST website.
Frequently asked questions
What is the interest rate on late GST payment?
18% a year under section 50 of the CGST Act, on the tax paid in cash, for each day of delay.
How do I calculate GST interest?
Tax paid late × 18% × days late ÷ 365. ₹1 lakh paid 43 days late gives ₹2,121.
Is GST interest charged on the gross tax or net tax?
On the net cash liability: the part paid in cash, after input tax credit, when the return is filed.
Is GST interest the same as the late fee?
No. Interest is for paying tax late; the late fee is for filing the return late. Both can apply.
From which date is GST interest counted?
From the day after the due date until the date the tax is paid.
Can GST interest be paid using input tax credit?
No. Interest must be paid in cash through the electronic cash ledger.