Interest u/s 234A, 234B, 234C Calculator
Calculate interest under sections 234A, 234B and 234C for late filing and short advance tax.
About the Interest u/s 234A, 234B, 234C Calculator
If your tax (after TDS) is ₹10,000 or more, you must pay advance tax in instalments: 15% by 15 June, 45% by 15 September, 75% by 15 December and 100% by 15 March. Presumptive-taxation businesses pay it all by 15 March, which this calculator doesn't model.
Interest is simple, 1% per month or part of a month, on amounts rounded down to the nearest ₹100: 234C on each short instalment (3 months each, 1 month for March; none if you paid at least 12% by June and 36% by September), 234B from 1 April if you paid less than 90% of your tax in advance, and 234A from the due date if you file late.
The formula
Interest = 1% × unpaid amount (rounded down to ₹100) × months or part months
Worked example
Example: Total interest = ₹3,195
- Inputs: Tax payable after TDS/TCS (assessed tax): ₹1,70,000; Advance tax paid by 15 June (cumulative): ₹11,000; By 15 September (cumulative): ₹44,000; By 15 December (cumulative): ₹88,000; By 15 March (cumulative): ₹1,10,000; Financial year ending in March: 2,026; Return due date: 1 January 2026; Date you file / pay the balance: 1 January 2026.
- Formula: Interest = 1% × unpaid amount (rounded down to ₹100) × months or part months
- Result: Total interest = ₹3,195
Things to keep in mind
- A simplified estimate; the Income Tax Department's computation is final.
Questions people ask
Does TDS count as advance tax?
TDS reduces the tax on which advance tax is due.
Can interest be waived?
Rarely; it's compensatory.
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.