Missed the ITR deadline? Belated, revised and updated (ITR-U) return windows explained

You had pencilled in 31 July 2026 as the last date to file your Income Tax Return for Assessment Year (AY) 2026-27 — the year that assesses income earned between 1 April 2025 and 31 March 2026 — and the calendar has slipped past it. The reassuring part, set out on the Income Tax Department's e-filing portal, is that the "File Return" button does not vanish at midnight: the Income-tax Act, 1961 keeps three recovery routes open, each under a different section and each carrying its own deadline and price tag. This Q&A maps the belated return (section 139(4)), the revised return (section 139(5)) and the updated return, or ITR-U (section 139(8A)), for AY 2026-27.

The Scenario

Imagine Kabir, a salaried professional in Pune whose employer deducted TDS through FY 2025-26 but who let the 31 July 2026 filing window pass while switching jobs. He now faces three separate questions: can he still file at all, can he fix a mistake in a return he has already lodged, and what happens if he discovers omitted income two years later. Each has a different answer and a different cost, so the first job is to identify which door he is standing in front of.

The three routes are not interchangeable. A belated return is for people who missed the original due date entirely; a revised return is for people who filed something (on time or belated) but now need to correct it; and ITR-U is a last-resort route that reopens even after the belated and revised windows have shut. The table below summarises the cut-off dates that apply to Kabir's AY 2026-27 filing.

Understanding which window is still open is worth real money: the difference between filing a belated return on 20 December 2026 and an ITR-U in 2030 can be tens of thousands of rupees in additional tax on the very same income.

Statutory Answer

Belated return — section 139(4). Where a return is not furnished by the due date under section 139(1), it may still be filed at any time before 31 December 2026 for AY 2026-27, that is, before three months prior to the end of the assessment year on 31 March 2027. The price of lateness is the fee under section 234F: Rs 1,000 where total income does not exceed Rs 5 lakh, and Rs 5,000 in every other case. Interest under section 234A also runs at 1% per month, or part of a month, on any unpaid self-assessment tax from the day after the due date until the return is filed. A crucial consequence sits in section 80 read with section 139(3): if you file belated, business losses and capital losses cannot be carried forward, although house-property loss and unabsorbed depreciation remain protected.

Revised return — section 139(5). A return already furnished — whether the original under 139(1) or a belated one under 139(4) — can be corrected by filing a revised return before the end of the assessment year, 31 March 2027 for AY 2026-27, or before the assessment is completed, whichever is earlier. There is no fee for revising itself; you pay only the tax on any additional income the revision brings to light. Since AY 2017-18, even a belated return can be revised, so Kabir is not locked out simply because his first attempt was late.

Updated return — section 139(8A). When both the belated and revised windows have closed, the ITR-U introduced by the Finance Act 2022 and widened by the Finance Act 2025 is the final option. For AY 2026-27 it can be filed within 48 months from the end of the assessment year — up to 31 March 2031. The statute imposes hard limits: only one updated return is permitted per assessment year, and an ITR-U cannot be used to reduce the total tax liability already declared, to increase a refund, or to report or enhance a loss. In other words, it is a mechanism to pay more, never to claim back. The additional income-tax is levied under section 140B and rises the longer you wait, as the next section shows.

Worked Resolution

Take Kabir's numbers for FY 2025-26. His gross salary is Rs 15,75,000; under the new tax regime he claims the standard deduction of Rs 75,000, leaving a taxable income of Rs 15,00,000. Applying the FY 2025-26 new-regime slabs, his tax works out as below. Because his income exceeds Rs 12,00,000, the section 87A rebate — now Rs 60,000 in the new regime — does not apply to him.

You can reproduce this with the income-tax calculator and compare regimes on the old-versus-new tool. Suppose Kabir's employer had already deducted Rs 1,00,000 as TDS, leaving Rs 9,200 of self-assessment tax unpaid. If he files a belated return on 15 September 2026, his extra outgo is the Rs 5,000 fee under section 234F (his income exceeds Rs 5 lakh) plus interest under section 234A at 1% per month for August and September 2026 — two months at 1% of Rs 9,200, or Rs 184. His total cheque is Rs 9,200 plus Rs 5,184, that is Rs 14,384.

Now change the facts. Suppose that only in June 2029 does Kabir realise he never disclosed Rs 2,00,000 of freelance income for FY 2025-26. Both the belated window (31 December 2026) and the revised window (31 March 2027) are long gone, so his sole route is an ITR-U before 31 March 2031. The extra Rs 2,00,000 stacks on top of his Rs 15,00,000, taxed at 15% on the slice to Rs 16,00,000 and 20% above it — Rs 35,000 of base tax plus 4% cess, or Rs 36,400 of additional tax before the section 140B loading. That loading depends entirely on timing, as the table shows for an AY 2026-27 ITR-U.

A June 2029 filing lands in the 24-to-36-month band, so the section 140B loading is 60%. On the Rs 36,400 of additional tax that is a further Rs 21,840, lifting the ITR-U charge to roughly Rs 58,240 before any section 234A and 234B interest is added on top. Had Kabir instead caught the omission and filed by 31 March 2028, the loading would have been 25% — about Rs 9,100 rather than Rs 21,840. The lesson is arithmetical, not moral: on money-your-life matters, delay compounds, and the same Rs 2,00,000 of income costs progressively more the longer it stays hidden.

FAQ

Can I still get a refund if I file a belated return for AY 2026-27?

Yes. A belated return under section 139(4) filed by 31 December 2026 can still claim a refund of excess TDS or advance tax, and the Income Tax Department pays interest under section 244A on eligible refunds. What you lose by filing late is the ability to carry forward business and capital losses, not the refund itself.

What is the difference between a revised return and an updated return?

A revised return under section 139(5) corrects a return you have already filed and can even reduce your tax or increase a refund, but it must be lodged by 31 March 2027 for AY 2026-27. An updated return under section 139(8A) reopens the case for up to 48 months but can only ever increase your tax; it cannot lower your liability, enlarge a refund or create a loss.

How many times can I revise my ITR?

Section 139(5) places no numerical cap on revisions, so a return can be revised more than once until 31 March 2027 or the completion of assessment, whichever is earlier. ITR-U is the opposite: section 139(8A) allows only one updated return per assessment year, so the single ITR-U you file for AY 2026-27 must be complete.

Will I pay a penalty if my income was below the taxable limit?

The section 234F fee is capped at Rs 1,000 where total income does not exceed Rs 5 lakh. If your gross total income is below the basic exemption limit — Rs 4,00,000 under the new regime for FY 2025-26 — and you had no obligation to file, no late fee applies, though voluntary filing before 31 December 2026 is still advisable to preserve refund claims.

Can I switch from the new regime to the old regime in a belated return?

A salaried taxpayer without business income exercises the regime choice in the return itself and can select the old regime in a belated return filed by 31 December 2026. Taxpayers with business or professional income must file Form 10-IEA within the section 139(1) due date to opt out of the default new regime, so a belated filing forecloses that switch for them. Use the old-versus-new comparison before deciding.

Does filing an ITR-U stop a notice or scrutiny?

No. Section 139(8A) bars an ITR-U where a search under section 132 or a survey under section 133A has been initiated, or where assessment or reassessment is pending or completed for that year. Filing before any such action — and before the 31 March 2031 outer limit — is what preserves the option; once a defective-return or scrutiny notice lands, the ITR-U route may already be shut.

How is the additional tax on ITR-U actually calculated?

Under section 140B the additional income-tax is 25%, 50%, 60% or 70% of the aggregate of the extra tax and interest payable, depending on whether you file within 12, 24, 36 or 48 months of the assessment year's end. You must clear this full amount before submitting the ITR-U, and the portal will not validate the return until the self-assessment challan matches. Verify the current position for your year on the income-tax e-filing portal before filing.