Section 234B of the Income Tax Act: Interest on Advance Tax Default

In summary

Section 234B of the Income Tax Act, 1961 applied when a taxpayer failed to pay advance tax or paid less than the required amount. Interest was generally charged when the advance tax paid was less than 90% of the assessed tax, subject to the applicable conditions.

• Old provision: Section 234B under the Income Tax Act, 1961.
• Current corresponding provision: Section 424 under the Income Tax Act, 2025.
• Interest rate: 1% per month or part of a month.
• Advance tax threshold: Generally Rs. 10,000 of tax liability.
• Key trigger: Insufficient advance tax, subject to the applicable 90% test.
• Purpose: Compensates for delayed payment of tax and encourages timely compliance.

From 1 April 2026, the Income Tax Act, 2025 applies to the relevant tax years. The corresponding provision is Section 424, and the Income Tax Department confirms that the interest rate remains 1% per month or part of a month.

Section 234B of the Income Tax Act, 1961 provided for interest when a taxpayer failed to pay advance tax or paid insufficient advance tax.

The provision was relevant where the taxpayer's assessed tax, after considering applicable tax credits, exceeded the prescribed threshold and the advance tax paid did not meet the required level.

For tax years governed by the Income Tax Act, 2025, taxpayers should refer to Section 424, which corresponds to the earlier Section 234B provision. The Income Tax Department confirms that the rate of interest has not changed.

Advance tax is income tax paid during the relevant financial year instead of waiting until the return is filed. It is generally applicable when the tax payable for the year, after considering applicable credits, is Rs. 10,000 or more.

This can be particularly relevant to people whose income is not fully subject to TDS. For example, additional income from interest, rent, capital gains from mutual fund schemes, or professional activities can increase the final tax liability.

The Income Tax Department states that the Rs. 10,000 threshold continues under the Income Tax Act, 2025.

Under the earlier Section 234B framework, interest generally applied when the advance tax paid was less than 90% of the assessed tax, subject to the conditions in the law.

The corresponding Section 424 under the Income Tax Act, 2025 retains the same broad interest framework. The Income Tax Department specifically states that interest is charged at 1% per month or part of a month for failure to pay advance tax or where advance tax paid is less than 90% of assessed tax.

The calculation can therefore become relevant even when some tax has already been paid through advance tax, TDS, or other eligible credits.

The basic calculation can be represented as:

Interest = Applicable shortfall × 1% × Number of months or part-months

The exact amount depends on the assessed tax, advance tax and other eligible tax credits, and the period for which interest is applicable.

For example, suppose a taxpayer has an assessed tax liability of Rs. 1,20,000 after applicable credits and has paid Rs. 80,000 towards advance tax. If the relevant shortfall is Rs. 40,000 and interest applies for four months:

Interest = Rs. 40,000 × 1% × 4 = Rs. 1,600

This example is illustrative. The actual calculation should follow the applicable statutory provisions and tax computation.

The 90% test determines whether insufficient advance tax can result in interest under the applicable provision.

Suppose the relevant assessed tax is Rs. 1,00,000. Ninety per cent of this amount is Rs. 90,000. If the applicable advance tax requirement is not met and only Rs. 70,000 has been paid, there is a shortfall against the 90% threshold.

The actual interest calculation must account for the tax amounts considered under the law, including applicable TDS, TCS, reliefs, and other eligible credits.

The interest rate remains 1% per month or part of a month under the corresponding Section 424 of the Income Tax Act, 2025. The Income Tax Department has expressly confirmed that there is no change in the interest rate from the earlier Section 234B framework.

A part of a month can therefore count as a full month for the relevant calculation. This is why paying the outstanding tax promptly can affect the amount of interest payable.

For taxpayers required to pay advance tax under the regular instalment system, the cumulative payment targets are generally:

Last updated: October 2026

Certain taxpayers, including those covered by presumptive taxation provisions, can have different advance tax payment requirements. The applicable provisions should therefore be checked for the relevant taxpayer and income type.

A resident senior citizen who does not have income from a business or profession can be exempt from advance tax requirements under the applicable provisions. The Income Tax Department has also clarified this position for the relevant tax framework.

Presumptive taxation can involve different payment requirements, so taxpayers covered by such provisions should not assume that the regular instalment schedule applies to them.

The exemption from advance tax does not mean that tax itself is not payable. It relates specifically to the obligation to pay tax in advance.

The most practical approach is to monitor your estimated annual income and tax liability during the year rather than waiting until the return-filing stage.

• Track additional income: Include interest, rent, capital gains, professional income, and other taxable sources in your estimate.
• Consider TDS and TCS: Account for tax already collected or deducted before determining any remaining liability.
• Review estimates: Recalculate your expected tax liability when income changes materially.
• Pay advance tax on time: Follow the applicable instalment schedule for your taxpayer category.
• Keep records: Maintain evidence of advance tax payments and other tax credits.

If your income includes investments, tools such as the mutual fund calculator, lumpsum calculator, and SIP calculator from Bajaj Finance can help you estimate investment values. They do not calculate your final Income Tax liability.

These provisions address different types of tax-payment or filing defaults.

Section 234B historically addressed insufficient or non-payment of advance tax, with the corresponding provision now being Section 424 under the Income Tax Act, 2025.

Section 234A dealt with interest for delay in furnishing the income tax return under the earlier Act.

Section 234C dealt with deferment of advance tax instalments. Under the Income Tax Act, 2025, the corresponding provisions are reorganised, so taxpayers should use the new Act's section references for current tax years.

Income from investments can create an additional tax liability that may not have been fully covered by TDS. Capital gains, interest income, and other taxable investment income can therefore affect the amount of tax payable during the year.

For example, an investor who realises taxable gains from mutual fund investments may need to factor those gains into their advance tax calculations. The SIP calculator from Bajaj Finance can help estimate investment values, while actual tax calculations should be based on the applicable Income Tax provisions. You can also use the step-up SIP calculator when modelling investments where contributions increase over time.

Section 234B was the provision under the Income Tax Act, 1961 for interest arising from specified defaults in advance tax payment. For tax years governed by the Income Tax Act, 2025, the corresponding provision is Section 424, with the interest rate continuing at 1% per month or part of a month.

Monitoring taxable income, accounting for TDS and other eligible credits, and paying advance tax according to the applicable requirements can help taxpayers manage their tax obligations and reduce avoidable interest.

Last reviewed: October 2026

Mutual funds are subject to market risk. Please read the scheme-related documents carefully before investing.