Indian taxpayers who missed this year's filing dates have until Dec. 31, 2026, to submit a belated income tax return for assessment year 2026-27, which covers income earned in the year to March 31, 2026. Those who have already filed but spotted an error now have more time than in past years: revised returns can be filed until March 31, 2027, although a fee applies after Dec. 31.

The calendar matters beyond India's salaried class. Non-resident Indians in Hong Kong, Singapore and the Gulf with rental income, capital gains or interest in India often file late or need to correct a return after a bank or broker statement turns up. For them, the next eight weeks are the cheapest window to fix the record.

India's belated return deadline and late fee

The original deadlines have passed for most individuals. Returns on ITR-1 and ITR-2, used by salaried people and many investors, were due July 31, and non-audit business and professional filers on ITR-3 and ITR-4 had until Aug. 31, Business Today reported. The split followed a staggered timeline announced in the Feb. 1 Budget, which gave non-audit businesses an extra month. Audited businesses have a separate date of Nov. 21, after the Central Board of Direct Taxes pushed back the audit calendar in September.

Anyone in the first two groups who has not filed can still do so as a belated return until Dec. 31. It costs money. A late fee under Section 234F is 1,000 rupees where total income does not exceed 5 lakh rupees (500,000 rupees) and 5,000 rupees above that, according to Business Today and ClearTax. Interest under Section 234A also runs on unpaid tax at 1% for each month or part of a month, according to a filing guide from accounting software maker Tally Solutions.

There is a less visible cost. Business losses and capital losses can be carried forward to later years only when the return was filed by the original due date, Tally said. A late filer with losses from stock trading in the year to March 2026 cannot use them to shelter future gains.

The Budget 2026 change to revised returns

Until this year, a revised return, filed to correct a mistake or omission in a return already submitted, had to be lodged by Dec. 31 of the assessment year, the same cutoff as belated returns. In the Union Budget presented on Feb. 1, Finance Minister Nirmala Sitharaman moved the revision deadline to March 31 of the assessment year, India TV News reported. A revised return can correct either an original return or a belated one, the outlet said.

The extra three months are not free. Revisions filed between Dec. 31 and March 31 attract a fee under Section 234I of 1,000 rupees for total income up to 5 lakh rupees and 5,000 rupees above that, according to ClearTax, which said the provision applies from March 1, 2026. Revised returns filed on or before Dec. 31 carry no such fee. Where the fee is due and unpaid, the revised return cannot be filed, ClearTax said.

That gives taxpayers a simple choice of dates for assessment year 2026-27:

• Dec. 31, 2026: last day for belated returns, and for revised returns without the new fee.
• March 31, 2027: last day for revised returns, with the Section 234I fee after Dec. 31.

When the window closes: updated returns

After those dates, the main remaining route is an updated return, known as ITR-U. Taxpayers can file one within 48 months of the end of the assessment year, which for assessment year 2026-27 runs to March 31, 2031, according to Tally. An updated return requires additional tax on top of the tax and interest due, it cannot be used to claim a new refund or additional benefits, and it cannot itself be revised, the guide said.

The additional tax rises the longer a filer waits, which makes the updated return an expensive option compared with a belated or revised return filed this year.

For filers abroad, the practical point is timing: an error found in a return for the year to March 2026 costs nothing extra to fix if the revised return goes in by Dec. 31.

This article is general information, not financial advice.