Section 234C Interest: Instalment Shortfall on 15 Jun / 15 Sep / 15 Dec / 15 Mar Deadlines

Section 234C of the Income Tax Act 1961 charges interest at 1% per month for three months on a shortfall at each of the first three advance-tax instalments (15 June, 15 September, 15 December), and 1% for one month on the 15 March shortfall. Safe harbours apply: paying at least 12% by 15 June and 36% by 15 September avoids 234C for those instalments. A company that misses an instalment cannot avoid the interest by paying more later — the interest is locked at each deadline.

What the law actually requires

Section 234C, Income Tax Act 1961 — interest for deferment of advance tax instalments. Unlike 234B (a single 90% year-end test), 234C is a checkpoint-by-checkpoint charge: each instalment date stands alone, and a shortfall at any one of them costs 1% per month for a fixed period regardless of what you pay later.

The instalment schedule (cumulative)

The percentages are cumulative — the 15 September instalment is not 30% of the year's tax, it is 45% less what was already paid. Companies routinely misread this as four equal quarterly payments of 25% and end up short at every checkpoint.

Safe harbours and cushions

Two instalments have statutory cushions; two do not:

The capital-gains and windfall proviso

The proviso to Section 234C(1) carves out income that arises after an instalment due date — capital gains, lottery/crossword/race winnings, gambling or betting income, dividend income, and certain new business income. If such income arises after a checkpoint, no 234C interest is charged for that instalment on the shortfall attributable to that income, provided the tax on it is paid in the remaining instalments, or by 31 March if it arises in the last quarter. A company that sells a property in February is not penalised for failing to predict it in June.

Worked example: Kaveri Foods Pvt Ltd misses its checkpoints

Kaveri Foods Pvt Ltd projects a tax liability of ₹20,00,000 for FY 2025-26 (AY 2026-27). Its payments and the resulting 234C:

Total 234C interest = ₹18,000.

The June instalment escapes because 12.5% exceeds the 12% safe harbour even though the statutory 15% was not met. The September and December checkpoints do not — 30% is below the 36% cushion and 60% is below the 75% full test, so interest is locked at ₹9,000 each, even though the company eventually pays 100% by 15 March. Paying more later does not reopen a closed checkpoint.

Now suppose Kaveri sold an industrial shed in December, generating a ₹4,00,000 capital gain. Without the proviso, the December shortfall would attract more interest; under the proviso, the shortfall attributable to that gain is excluded from the December computation, provided the tax on the gain is paid in the remaining instalments or by 31 March. The company documents the gain's timing and pays the related tax with its March instalment.

What a director should actually watch

• Aim for the safe harbours, not the statutory percentages, in Q1 and Q2. Pay at least 12% by 15 June and 36% by 15 September. These are cheaper than the statutory 15%/45% and fully avoid 234C for those instalments.
• Pay the full 75% and 100% for December and March. There is no cushion — a 74.9% December is charged in full.
• Pay through Challan ITNS-280, Major Head 0020, Minor Head 100 (advance tax). A payment tagged to the wrong minor head does not extinguish the instalment obligation, and the 234C computation will not recognise it.
• Document one-off gains and use the proviso. If a capital gain or windfall arises late in the year, note the timing, pay the tax in the next instalment, and the earlier shortfall attributable to it is excluded.
• Reconcile against Form 26AS after each instalment. Confirm the challan appears with the right assessment year (AY 2026-27 for FY 2025-26) — a wrong AY is the second most common error after a wrong minor head.

A note for presumptive-taxation assessees

For individuals, HUFs and firms on presumptive taxation under Sections 44AD or 44ADA, the entire advance tax is payable in a single instalment by 15 March. Missing that single date attracts 234C at 1% per month for one month on the shortfall — there are no quarterly checkpoints to absorb the delay. The corporate schedule above applies to companies and other non-presumptive assessees.

FAQ

What is the 234C interest rate?
1% per month for 3 months on the shortfall at 15 June, 15 September and 15 December; 1% for 1 month on the 15 March shortfall. Simple interest, computed on each checkpoint independently.

Is there any cushion below the statutory percentages?
Yes, for the first two instalments: no 234C if you have paid at least 12% by 15 June and 36% by 15 September. December and March have no cushion.

What if I pay 100% by 15 March but missed earlier instalments?
The earlier checkpoints are closed and the interest stands. Paying the full year's tax by March does not reverse June and September interest. — some summaries claim a full payment by 15 March waives the December shortfall; the statutory position is that December has no cushion, so confirm with your CA before relying on it.

Does the capital-gains proviso cover a property sold in December?
Yes, if the gain arose after the earlier instalment dates, the shortfall attributable to it is excluded from the December computation, provided the tax is paid by 31 March.

Do these instalments apply to a company?
Yes. A company pays the same cumulative schedule (15/45/75/100%) with no minimum-liability exemption.

Is 234C interest deductible?
No. Like 234B, it is disallowed under Section 40(a)(ii) as part of income tax paid.

Use the advance tax calculator to model your instalments and safe harbours: /tools/advance-tax-calculator. For a tax planning and compliance review, visit pvtltd.co.

Sources

• Section 234C, Income Tax Act 1961
• Section 208, Section 211(1), Income Tax Act 1961 (advance tax liability and instalments)
• Proviso to Section 234C(1) (capital gains / winnings carve-out)
• Section 40(a)(ii) ITA 1961 (disallowance of interest on income tax)

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