Compliance Calendar

ITR-3/ITR-4 Due Date 31 August 2026: Last-Day Checklist and Section 234F/234A Penalty Guide

Published 31 Aug 2026· Updated 31 Aug 2026· 5 min read

The extended due date for filing Income Tax Returns in Form ITR-3 and ITR-4 for non-audit taxpayers, Assessment Year 2026-27, falls today, 31 August 2026. For practitioners still closing out client filings this evening, the practical question is no longer whether the return can be filed on time, but what it actually costs if it slips past midnight, and whether that cost is worth absorbing versus pushing through a rushed same-day filing.

Sidebar: A belated return under Section 139(4) remains available up to 31 December 2026 for AY 2026-27. Filing late is not the same as not filing, but it carries a fixed cost, and it permanently closes one specific door: the right to carry forward a business loss.

Why It Matters

Two distinct financial consequences attach to a return filed after 31 August 2026, and they operate independently of each other. Section 234F imposes a flat late fee based on total income, irrespective of whether any tax remains unpaid. Section 234A separately charges interest at 1% per month or part of a month on any self-assessment tax that remains outstanding as of the due date, running from the day after the due date to the actual date of filing. A practitioner who treats these as a single combined penalty risks under-advising a client, since even a taxpayer with zero outstanding tax still owes the Section 234F fee in full. Separately, and often overlooked, Section 80 read with Section 139(3) bars the carry-forward of business losses (though not unabsorbed depreciation) once a return becomes belated under Section 139(4) rather than filed within the original due date under Section 139(1).

Key Takeaways

The extended due date for ITR-3 and ITR-4 (non-audit taxpayers), AY 2026-27, is 31 August 2026.
A belated return under Section 139(4) remains available up to 31 December 2026 for AY 2026-27 — the return can still be filed, just at a cost.
Section 234F charges a flat late fee (₹5,000 where total income exceeds ₹5 lakh, ₹1,000 where it does not) regardless of whether any tax is outstanding.
Section 234A adds interest at 1% per month or part of a month on any unpaid self-assessment tax, computed from the day after the due date to the date of actual filing.
Once a return becomes belated under Section 139(4), Section 80 read with Section 139(3) permanently bars carrying forward a business loss to future years — though it can still be set off against other income in the current year.

Practical Implications

A worked illustration makes the arithmetic concrete. Consider a freelance professional filing ITR-3 for AY 2026-27 with total taxable income of ₹8,00,000, of which ₹15,000 of self-assessment tax remains unpaid as of today. If the return is instead filed on 15 October 2026: the Section 234F fee is a flat ₹5,000, since total income exceeds ₹5 lakh. The Section 234A interest runs from 1 September to 15 October 2026, spanning two part-months (September, and part of October), at 1% per month on ₹15,000, giving ₹300 (1% × ₹15,000 × 2). The combined avoidable cost of the delay is ₹5,300 — and if that taxpayer also has a business loss to carry forward, that right is lost permanently under Section 80 read with Section 139(3), even though the loss can still be set off against other income this year. For clients close to the finish line, this makes today’s filing meaningfully more valuable than the fee alone suggests.

Action Checklist

File any ITR-3/ITR-4 clients still pending today, before midnight, to avoid the Section 234F fee and Section 234A interest altogether.
Where same-day filing is genuinely not possible, pay the estimated self-assessment tax today regardless, to stop the Section 234A interest clock even before the return itself is filed.
For clients with a business loss this year, flag the carry-forward consequence explicitly before advising them to delay — many will not realise the loss of that right until it is too late to fix.
If unabsorbed depreciation is part of the picture, note that Section 32(2) allows it to carry forward indefinitely regardless of the filing date — it is not affected by a belated return.
If a return does slip past today, treat 31 December 2026 as the hard outer limit for AY 2026-27 belated filings under Section 139(4) — there is no further extension beyond it.

Relevant Sections, Rules and Notifications

Section 139(1), Income-tax Act, 1961 — original due date for return filing.
Section 139(4), Income-tax Act, 1961 — belated return, permissible up to 31 December 2026 for AY 2026-27.
Section 139(3) read with Section 80, Income-tax Act, 1961 — bars carry-forward of business loss where the return is belated.
Section 234F, Income-tax Act, 1961 — flat late fee for delayed filing.
Section 234A, Income-tax Act, 1961 — interest on unpaid self-assessment tax for delayed filing.
Section 32(2), Income-tax Act, 1961 — unabsorbed depreciation, carries forward indefinitely irrespective of filing delay.
Note: The Income-tax Act, 2025 renumbers Section 234F as Section 428 and Section 139 as Section 263, but that renumbering does not govern AY 2026-27 filings, which remain under the Income-tax Act, 1961.

Frequently Asked Questions

Q1. Can ITR-3 or ITR-4 still be filed after 31 August 2026? Yes. A belated return under Section 139(4) can be filed up to 31 December 2026 for AY 2026-27, though it will attract the Section 234F fee and, where applicable, Section 234A interest.

Q2. Does the Section 234F fee apply even if all tax has already been paid? Yes. Section 234F is a flat fee tied to total income, not to any tax shortfall — it applies purely because the return itself is filed after the due date.

Q3. If a client’s return becomes belated, can a business loss still be used at all? Yes, but only in the current year. Section 80 read with Section 139(3) bars carrying the loss forward to future years once the return is belated, though it can still be set off against other income in the year it was incurred. Unabsorbed depreciation under Section 32(2) is unaffected and continues to carry forward indefinitely.

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Author & Disclaimer

Published by the Finoscape Editorial Desk, drawing on the provisions of the Income-tax Act, 1961 as applicable for Assessment Year 2026-27. This article is for general professional information only and does not constitute individual tax advice. Readers should consult a qualified Chartered Accountant for advice specific to their facts before acting on any of the above.