Three different doors. A revised return under s.139(5) and a belated return under s.139(4) both close on 31 December of the assessment year and cost only the s.234F fee and s.234A interest. After that, only an updated return under s.139(8A) is available — now up to 48 months from the end of the assessment year, with additional tax of 25% to 70% under s.140B.
Start with the original due date under s.139(1). For FY 2025-26 (AY 2026-27) the due date for an ordinary individual return was 31 July 2026; audit cases and transfer pricing cases have later dates.
A belated return under s.139(4) is what you file if you miss that date. The deadline is 31 December of the assessment year, or completion of the assessment if earlier. For FY 2025-26 that is 31 December 2026. The cost is a fee under s.234F of Rs 5,000 where total income exceeds Rs 5 lakh and Rs 1,000 where it does not, with no fee where income is below the exemption limit, plus simple interest under s.234A at 1% a month.
Belated filing carries two consequences that are worse than the fee. Business losses and capital losses cannot be carried forward, though a house property loss can. And commentary is that a belated return is filed under the concessional regime even if Form 10-IEA was filed on time, so the old regime is effectively lost for that year.
A revised return under s.139(5) corrects a return already filed. It runs to the same 31 December of the assessment year cut-off, and there is no additional tax on a revision. A belated return can itself be revised, provided both the belated return and the revision are filed by that date. If you are still inside this window, revise; there is no reason to reach for an updated return.
Once 31 December has passed, s.139(8A) is the only route. The updated return, ITR-U, allows voluntary disclosure of income that was omitted. It is available to individuals, HUFs, firms, LLPs, companies and trusts, and can be filed even by someone who never filed an original return at all. Only one updated return may be filed for a given assessment year.
The window was doubled by the Finance Act, 2025 from 24 months to 48 months from the end of the relevant assessment year, effective 1 April 2025, and applies to any assessment year whose window had not already expired by that date. The additional tax under s.140B moves in four steps by reference to when you file: 25% where the return is filed within 12 months from the end of the assessment year, 50% between 12 and 24 months, 60% between 24 and 36 months, and 70% between 36 and 48 months. The percentage is applied to the aggregate of the additional tax and interest payable, not to the omitted income.
What ITR-U cannot do matters as much as what it can. It cannot be used to reduce your tax liability, to claim or increase a refund, or to create or increase a loss. It is not available where a search under s.132 or a survey under s.133A is pending against you, where assessment or reassessment proceedings are pending or concluded for that year, where prosecution has been initiated, or where you have already filed one updated return for that year.
The gap between a revised return and an updated return is the difference between no extra tax and up to 70% on top of the tax and interest. That gap opens on 1 January of the assessment year, which makes December the single most important month for anyone who suspects an error. The 48-month window also means old years you assumed were closed may still be open — and so may the department's ability to look at them.
I paid advance tax for the year but had not filed my return when the search took place. Can the department still call that income undisclosed?
Can interest under ss.234A, 234B and 234C be waived?
I deducted TDS during the year but paid it after 31 March, though before I filed my return — can the expense still be disallowed under section 40(a)(ia)?
I have given the excise authorities a bank guarantee for unpaid bottling fee. Does that count as actual payment under section 43B - and is bottling fee even covered by section 43B?
Our amalgamation was sanctioned long after the deadline for a revised return. Must the department accept revised returns filed to give effect to the scheme?
You want to make a claim you missed, but the time to revise the return has gone. Can you just write to the officer?
My company is registered outside the taxable territory but run from Delhi. Where is it resident?
A declaration was required by the due date and you filed it late. Is that fatal?
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