Belated and Revised ITR Under Section 139: Guide 2026

You missed the income tax return deadline, or you filed and then spotted a mistake. Either way the panic is the same: what do I file now, and how much will it cost me? This guide maps your exact situation to the correct section of the Income Tax Act, 1961, so you stop guessing.

Start here. Pick the line that matches you, then read the section.

1. I missed the 31 July 2026 due date entirely and have not filed at all → file a belated return under Section 139(4).
2. I already filed on time but the return has a wrong figure (income, deduction, bank details, wrong ITR form) → file a revised return under Section 139(5).
3. I filed late (belated) and now want to correct that belated return → you can still revise it under Section 139(5), as long as the deadline has not passed.
4. The 31 December deadline has already gone → neither 139(4) nor 139(5) is available. Your only route is an Updated Return (ITR-U) under Section 139(8A). See our ITR-U updated return guide.

The single most important date for both belated and revised returns for AY 2026-27 (FY 2025-26) is 31 December 2026 (or before your assessment is completed, whichever is earlier).

A belated return is an income tax return filed after the original Section 139(1) due date but on or before 31 December of the assessment year (or before the assessment is completed, whichever is earlier). It is filed under Section 139(4) and is the standard fix when you simply missed the deadline.

Filing late is not free. Under Section 234F of the Income Tax Act, 1961:

• Rs 5,000 late filing fee in the normal case.
• Rs 1,000 if your total income does not exceed Rs 5 lakh.
• Nil if your income is below the basic exemption limit (you were not required to file).

On top of this, Section 234A interest at 1 percent per month runs on any unpaid tax from the due date until you pay. So the longer you wait, the more it stacks.

This is the part most people miss, and it can cost far more than the Rs 5,000 fee.

The new tax regime is the default. To choose the old regime (with its 80C, 80D, HRA and home-loan deductions), eligible taxpayers must exercise that option on or before the Section 139(1) due date.

• Taxpayers with business or profession income must file Form 10-IEA by the due date. The income tax portal FAQ is explicit: *“Form 10-IEA should be filed on or before the due date of filing of return as specified u/s 139(1)“* and *”If taxpayer files the form after the due date, the form will be treated as Invalid.”*
• The same FAQ warns: *“In case you want to opt out of new tax regime and you fail to file the form within due date, you will not be eligible to get the benefit of old tax regime in your ITR.”*
• Salaried and other non-business taxpayers choose the old regime simply by selecting it inside the ITR, but again only in a return filed by the due date.

Bottom line: if you file a belated return under Section 139(4), you are locked into the new regime. You cannot claim old-regime deductions, even if the old regime would have saved you tax. For many people this loss dwarfs the late fee. Decide your regime before the due date. See switching tax regime and Form 10-IEA.

A belated return blocks most loss carry-forward, because Section 80 allows carry-forward only if the loss return was filed within the Section 139(1) due date.

You can still set off losses against the current year's income even in a belated return. It is the carry-forward to future years that you lose for business and capital losses. House property loss and unabsorbed depreciation are the two exceptions that survive a late filing.

1. Log in at the income tax e-filing portal and open File Income Tax Return.
2. Select AY 2026-27 and the correct ITR form. Not sure which? Use our which ITR form to file guide.
3. For belated: choose filing section 139(4). For revised: choose 139(5) and enter the acknowledgement number and date of the original return.
4. Pay any self-assessment tax, plus the 234F fee and 234A interest, before submitting.
5. Submit and then e-verify within 30 days. An unverified return is treated as never filed. If yours failed, see e-verification failed action.

A revised return replaces the earlier return entirely. Key points:

• You can revise an original or a belated return.
• You can revise more than once before the deadline; the last valid revised return stands.
• The deadline is the same 31 December 2026 for AY 2026-27.
• A revised return cannot change your tax regime if the original was filed late or after the option window. Revision fixes figures, not the regime lock.

Consider a salaried professional in Pune with total income of Rs 8 lakh who forgot to file by 31 July 2026. In October 2026 they file a belated return under Section 139(4). They pay a Rs 5,000 fee under Section 234F (income above Rs 5 lakh) plus 234A interest on a small tax shortfall. The bigger hit: they had planned to claim Rs 1.5 lakh under 80C and Rs 25,000 under 80D in the old regime, but as a belated filer they are forced into the new regime and lose those deductions. The extra tax outgo from the lost old-regime benefit far exceeds the Rs 5,000 fee. The lesson is simple: file by the due date if you want the old regime.

• Assuming you can still pick the old regime late. You cannot. The new regime is default once the 139(1) window closes.
• Forgetting to e-verify. Under the e-filing rules a return not verified within 30 days is invalid, fee paid or not.
• Trying to carry forward business or capital losses. Section 80 blocks this for belated returns.
• Waiting past 31 December. After that only ITR-U under Section 139(8A) works, with 25 to 70 percent extra tax.

No. For AY 2026-27 the belated and revised return window closes on 31 December 2026. After that your only option is an Updated Return (ITR-U) under Section 139(8A), which carries additional tax.

Not always. The Section 234F fee is Rs 1,000 if total income is up to Rs 5 lakh, and nil if your income is below the basic exemption limit so that filing was not mandatory.

No. The old regime requires the option to be exercised by the Section 139(1) due date (Form 10-IEA for business income, or selection in the ITR otherwise). Belated filers are locked into the new regime.

Yes. A belated return can be revised under Section 139(5) up to 31 December 2026, but revision cannot restore the old-regime option you lost by filing late.

Most business and capital losses cannot be carried forward on a belated return. House property loss and unabsorbed depreciation are the exceptions that survive. Current-year set-off is still allowed.

• Check your exact due dates with the deadline calculator.
• Plan instalments using the advance tax due dates guide.
• Read The RTI Playbook for using the right to information to track stuck tax matters and grievances.

• Income Tax Department, Form 10-IEA FAQ (regime option and due date): https://www.incometax.gov.in/iec/foportal/help/statutory-forms/popular-form/form-10-IEA-faq
• Income Tax Department, New Tax vs Old Tax Regime FAQs: https://www.incometax.gov.in/iec/foportal/help/new-tax-vs-old-tax-regime-faqs
• Income Tax Act, 1961 - Sections 139(1), 139(4), 139(5), 139(8A), 234F, 234A, 80, 71B and 32(2)