Interest u/s 234c

Section 243C: Delay in Periodic Payment of Tax:

Income tax should be paid on time every financial year to avoid interest and penalty on late payment. Advance tax can be paid on the dates mentioned below:

15% of advance tax on or before June 15 in case of corporate taxpayer.

45% and 30% tax advance to be paid by corporate and noncorporate taxpayer respectively, on or before September 15.

60% and 75% of tax advance by non-corporate and corporate taxpayers should be paid on or before December 15.

100% tax advance by both corporate and noncorporate taxpayers should be paid on or before March 15.

Calculating Interest Penalty:

The interest penalty is 1% of the tax amount due from the above mentioned dates till the actual payment date. The amount to be paid, is calculated after tax deductions under Sections 90, 91, and 115JD. Here’s is how interest penalty is calculated, under Section 234C:
Non-Corporate Taxpayer:

1% interest rate per month for a period of 3 months is computed for advance tax less than 30% of the amount on or before September 15.

In case advance tax is paid on or before December 15 is less than 60% of the taxable amount, interest of 1% for a period of 3 months is levied.

For amount less than 100% of the advance tax paid on or before March 15, a simple interest of 1% per month is computed.

Corporate Taxpayer:

If 15% of the amount is already deposited on or before June 12, and advance tax is less than 12%, then an interest of 1% per month for three months is levied.

In case 45% of the tax is deposited on or before September 15, and advance tax is less than 36%, a penalty for 3 months is charged at 1% of the interest per month.

When 75% tax is paid before December 15, and payable amount is less than 75%, 1% simple interest per month is computed for a period of 3 months.

When advance tax to be paid is less than 100% of the amount already paid as tax, then a simple interest of 1% is charged