GST Late Fee Calculator

Work out the late fee and interest for filing GSTR-3B or GSTR-1 after the due date.

Due date of the return	2026-10-20
Date filed	2026-11-08
Nil return	No
Aggregate turnover last year	Up to ₹1.5 crore
Net tax paid in cash late	₹50,000

Due date of the return

Date filed

Nil return

Aggregate turnover last year

Net tax paid in cash late

₹

Late fee + interest

₹1,418

19 days late: late fee ₹950 (₹50/day, half CGST and half SGST, capped at ₹2,000) and interest ₹468 at 18% a year on tax paid late in cash.

What being late costs

Late fee67%: ₹950
Interest at 18%33%: ₹468

About the GST Late Fee Calculator

For late GSTR-3B and GSTR-1 returns, the late fee is ₹50 a day (₹25 CGST + ₹25 SGST), or ₹20 a day for nil returns, capped at ₹500 for nil returns and ₹2,000, ₹5,000 or ₹10,000 depending on turnover (Notifications 19/2021 and 20/2021). Interest under Section 50 is 18% a year on tax paid late in cash, counted from the day after the due date. GSTR-3B is due on the 20th of the following month for monthly filers.

The formula

Late fee = min(days × ₹50, cap); interest = tax × 18% × days ÷ 365

Worked example

Example: Late fee + interest = ₹9,841

Inputs: Due date of the return: 1 January 2026; Date filed: 15 November 2026; Nil return: No; Aggregate turnover last year: Up to ₹1.5 crore; Net tax paid in cash late: ₹50,000.
Formula: Late fee = min(days × ₹50, cap); interest = tax × 18% × days ÷ 365
Result: Late fee + interest = ₹9,841

Questions people ask

Is the late fee charged on IGST?

No, it's levied under CGST and SGST.

Is interest charged on the full tax?

Only on the part paid in cash, not via input tax credit.

Sources

The rules and rates this calculator uses come from the official pages below. Its results are estimates, not an official determination, and rules change, so check the latest figures there before you act on them.