Interest and penalty on advance tax shortfall

Thanks for the detailed reply

Thanks for the detailed reply

Section 234C applies when you defer a specific installment (15% by June 15, 45% by September 15, 75% by December 15, 100% by March 15) and charges 1% per month for 3 months on the shortfall at each date. Section 234B applies when total advance tax paid is below 90% of final liability, attracting 1% monthly from April 1 of the assessment year. A shortfall at June 15 only triggers 234C interest for that quarter. This [FY 2026-27 tax compliance calendar](https://taxgarden.in/resources/tax-compliance-calendar-fy-2026-27-india-sme) has the full advance tax schedule with the installment percentages and calculation method.

The advance tax interest regime has two separate sections ,  most people confuse them. Here is how they work:

SECTION 234C: QUARTERLY SHORTFALL INTEREST
This applies when you fail to pay the MINIMUM required at each quarterly due date:
- June 15: at least 15% of estimated annual tax
- September 15: at least 45% cumulative
- December 15: at least 75% cumulative
- March 15: at least 100%

Interest rate: 1% per month (or part thereof) on the shortfall at each date
Duration: 3 months for June, September, and December deadlines; 1 month for March

EXAMPLE: Annual tax liability = Rs 1,00,000. June 15 payment = Rs 10,000 (paid), required = Rs 15,000. Shortfall = Rs 5,000. 234C interest = Rs 5,000 x 1% x 3 months = Rs 150.

SECTION 234B: ANNUAL SHORTFALL INTEREST
This applies if you have paid less than 90% of your total tax liability by March 31:
- Rate: 1% per month on the shortfall from April 1 until the actual payment date
- This is in ADDITION to 234C

KEY POINT: Even if you paid the correct percentages at each quarterly date, 234B can still apply if your total payment falls short of 90% by year end.

NO INTEREST IF: You are a salaried employee whose employer deducts full TDS and your net tax liability after TDS is below Rs 10,000.

For a full guide on income tax changes and advance tax rules for FY 2026-27, Tax Garden has published a detailed guide: https://taxgarden.in/blog/income-tax-rules-2026-key-changes-india