The late fee slabs, interest calculation, what you permanently lose by filing belated, and a worked example showing the full stacked cost of missing the deadline.
Under the Income-tax Act, 2025, filing your ITR after the due date triggers multiple costs that stack on top of each other. The late fee is just the first one. Here is exactly what you pay, how it is calculated, and a real worked example showing every layer.
The late fee — two slabs
The late fee for a belated return is straightforward:
| Total Income | Late Fee | |---|---| | Up to Rs 5,00,000 | Rs 1,000 | | Above Rs 5,00,000 | Rs 5,000 |
If your total income is below the basic exemption limit (Rs 3,00,000 under the new regime for individuals below 60), no late fee applies even if you file late. The late fee is added to your tax liability and must be paid at the time of filing.
Interest on unpaid tax — 1% per month
If any tax remains unpaid after the due date (31 July 2026 for most individuals), interest is charged under the Income-tax Act, 2025 at 1% per month or part of a month on the outstanding amount. The clock starts from the day after the due date and runs until the date of actual payment.
What counts as "a part of a month": even one day into a new month triggers a full month's interest. If you pay on 3 August, that is 2 full months (August and the part of July counted as a full month) — so it is 2% of the outstanding tax.
Interest is computed on the net amount payable: your total tax liability minus TDS, advance tax, and self-assessment tax already paid.
The hidden costs — what you permanently lose
### Loss carry-forward is gone
This is the cost nobody talks about. If you had a capital loss this year — from selling shares, mutual funds, or property at a loss — you can normally carry it forward and set it off against future capital gains for up to 8 assessment years. But this carry-forward is available only if you file your return on or before the due date. File a belated return, and that loss can never be used. If you booked a Rs 1,50,000 short-term capital loss, filing late means you permanently lose the ability to save approximately Rs 30,000 in future capital gains tax (at 20% STCG rate).
Business losses are treated identically — no carry-forward on a belated return. House property loss (from a home loan interest exceeding rental income) can be carried forward even on a belated return, which is an exception worth noting.
### Delayed refund
If you are owed a refund, filing on time generally means faster processing. The department prioritises timely returns. Belated returns are processed, but your refund may take months longer.
### No regime switching (in some cases)
If you file a belated return, your ability to switch between the old and new tax regimes may be restricted depending on the specific circumstances. The general rule: once a belated return is filed, certain elections that are available only in a return filed by the due date are lost. Verify the current position on incometax.gov.in for your specific situation.
Worked example: the full stacked cost
Let us work through a real scenario to show every layer of cost.
Scenario: A salaried individual earning Rs 9,00,000 has unpaid tax of Rs 18,000 after accounting for TDS. They file on 15 September 2026 — 46 days late.
| Cost Layer | Calculation | Amount | |---|---|---| | Late fee (income above Rs 5L) | Flat | Rs 5,000 | | Interest on unpaid tax | Rs 18,000 × 1% × 2 months (August + part of July) | Rs 360 | | Lost capital loss carry-forward | Rs 80,000 long-term loss × 12.5% tax rate = potential future tax saved | Rs 10,000 (gone forever) | | Total real cost | | Rs 15,360 |
The late fee of Rs 5,000 is visible and obvious. The Rs 360 in interest is small. The Rs 10,000 in permanently lost tax benefit is invisible — and it is the biggest item.
Who pays zero even when filing late
You pay no late fee if your total income (gross total income minus deductions) is below the basic exemption limit. For most individuals under 60, that limit is Rs 3,00,000 under the new tax regime. If your total income is Rs 2,80,000, you file late, and your total income stays below Rs 3,00,000 — the late fee is zero.
For senior citizens (60-79 years), the basic exemption limit is Rs 3,00,000. For super senior citizens (80+), it is Rs 5,00,000. The Rs 5,00,000 income threshold for the Rs 5,000 late fee is separate from the exemption limit — they are different concepts. If you are a super senior citizen with total income of Rs 4,50,000, your basic exemption is Rs 5,00,000 (so no tax is due on the income), but your income exceeds Rs 5,00,000 for the late fee? No — Rs 4,50,000 is below Rs 5,00,000, so the late fee would be Rs 1,000 (the lower slab).
The absolute last date
A belated return for AY 2026-27 can be filed up to 31 December 2026. After that, you generally cannot file a return for that year. There is a further provision for an updated return (ITR-U) which can be filed within 24 months from the end of the assessment year, but it carries an additional tax of 25% or 50% of the tax and interest payable, depending on when it is filed.
Belated return vs Updated Return (ITR-U)
| | Belated Return | Updated Return (ITR-U) | |---|---|---| | Window | Up to 3 months from end of AY | Within 24 months from end of AY | | Late fee | Rs 1,000 / Rs 5,000 | None separately, but additional tax applies | | Additional tax | Interest only | 25% extra tax (if filed within 12 months) or 50% (if filed after 12 months) | | When to use | You simply missed the original deadline | You filed something, but later discovered unreported income | | Loss carry-forward | Lost | Lost |
ITR-U is not a cheaper belated return. It is a mechanism to voluntarily disclose income you previously omitted. Using it because you missed the original deadline will cost you more than a belated return.
Frequently Asked Questions
### What is the penalty for filing ITR after the due date? A late fee of Rs 1,000 (total income up to Rs 5 lakh) or Rs 5,000 (income above Rs 5 lakh), plus interest at 1% per month on any unpaid tax, plus permanent loss of loss carry-forward benefits.
### Can I file ITR after 31 July 2026 without any penalty? Only if your total income is below the basic exemption limit. Everyone else pays the late fee. There is no provision to waive the late fee for genuine reasons.
### How is interest on late ITR calculated? Interest is charged at 1% per month or part of a month on the net tax payable (total tax minus TDS and advance tax). It starts the day after the due date and runs until the actual payment date. Even one day into a new month triggers a full month's interest.
### Do I lose all my deductions if I file a belated return? No. Most deductions (80C, 80D, home loan interest, NPS) remain available on a belated return. What you lose is loss carry-forward — capital losses and business losses can only be carried forward if the return is filed on time.
### What is the last date for a belated return for AY 2026-27? 31 December 2026. After that, only an updated return (ITR-U) is possible, which carries additional tax of 25-50%.
### Does filing a belated return increase my chance of scrutiny? Not by itself. Scrutiny is based on risk parameters set by CBDT, not on whether a return was filed on time or late. However, consistent late filing over multiple years may be a factor in some risk-assessment models.
Disclaimer
This article is for educational purposes only. Tax provisions, rates and deadlines are subject to change. Verify current information on incometax.gov.in before filing. For decisions that affect your tax liability, consult a qualified tax professional.