ITR due date, late fee and interest

ITR due date for FY 2025-26 (AY 2026-27): 31 July 2026 if you have no business income; 31 August 2026 if you have business or professional income and no audit; 21 November 2026 (extended from 31 October by CBDT Circular 07/2026) if your accounts must be audited. Missed it? You can still file a belated return until 31 December 2026: you pay a flat late fee of ₹1,000 (income up to ₹5 lakh) or ₹5,000, interest of 1% a month on tax still unpaid, and you lose the old regime and the carry-forward of most losses. After 31 December only an updated return (ITR-U) is left, at 25% to 70% extra. For tax year 2026-27 the dates are 31 July, 31 August and 31 October 2027.

Due dates

The due date depends on your income and on whether your accounts must be audited, not on which ITR form you use. The Finance Act, 2026 added a separate 31 August date for business and professional income without audit; before, it was 31 July.

FY 2025-26 (assessment year 2026-27), return due in 2026

Transfer-pricing cases (report under section 92E): 30 Nov 2026. The tax audit report moved from 30 Sep to 21 Oct 2026. The official tax calendar shows no extension of 31 July or 31 August 2026.

Tax year 2026-27, return due in 2027

From 1 April 2026 the Income-tax Act, 2025 uses one "tax year" in place of "previous year" and "assessment year". Tax year 2026-27 runs from 1 April 2026 to 31 March 2027.

Transfer-pricing cases: 30 Nov 2027. No extension so far.

Which due date counts for interest

Interest for a late return (234A; section 423 from tax year 2026-27) runs from the day after your due date. When CBDT extends a date, the extended date is normally used: for audit cases in FY 2025-26, interest would start on 22 November 2026. If CBDT extends a date again, use the new date. In the income tax calculator you choose the date to use: the official date, the extended date (selected for you when there is one), or another date you type in.

Who has to file

The late fee applies only if you had to file. You have to file if:

• your income before deductions is above the basic exemption limit: ₹4 lakh in the new regime (₹2.5 lakh, ₹3 lakh at 60–79 or ₹5 lakh at 80+ in the old regime). The ₹12 lakh rebate does not change this: income of ₹4–12 lakh with nil tax must still be filed;
• or, even with lower income: deposits over ₹1 crore in current accounts or ₹50 lakh or more in savings accounts; over ₹2 lakh spent on foreign travel; electricity bills over ₹1 lakh; business turnover over ₹60 lakh or professional receipts over ₹10 lakh; TDS and TCS of ₹25,000 or more (₹50,000 at 60+); or you are a resident with assets or signing authority outside India. These come from section 139(1) and Rule 12AB for FY 2025-26, and from section 263(1) and Rule 163 of the Income-tax Rules, 2026 for tax year 2026-27, which keeps the same list.

Not required: a resident aged 75 or more whose only income is pension and interest from the same bank, after giving the bank the declaration (section 194P). If you did not have to file and file late only to claim back TDS, there is no late fee.

If you file late, up to 31 December

A return filed after the due date but by 31 December 2026 (FY 2025-26) or 31 December 2027 (tax year 2026-27) is a belated return (section 139(4); 263(4)). It is a valid return, but it costs more:

• Late fee: ₹5,000, or ₹1,000 if total income is ₹5 lakh or less. It is the same whether you are one day or five months late, and it is due even when tax is nil (234F; 428(a)). Example: total income ₹4.6 lakh, nil tax after the rebate, filed in September 2026: fee ₹1,000. Total income ₹3.8 lakh and no other reason to file: no fee.
• Interest: 1% a month on tax still unpaid (234A), on top of interest for short advance tax (234B and 234C). Worked examples below.
• Only the new regime: the old regime can be chosen only in a return filed by the due date, so 80C, 80D, HRA and home-loan interest are lost. With business income, the old regime is chosen in Form 10-IEA, which must be filed by the due date (115BAC(6); 202(4); ITR validation rule 151).
• Losses: business, speculation and capital-gains losses of the year cannot be carried forward; they can still be set off in the same year. A house-property loss can still be carried forward (139(3) and 80; 121).
• Some deductions: for FY 2025-26, deductions such as 80JJAA, 80QQB (authors' royalty) and 80RRB (patent royalty) need a return filed on time (80AC).
• Refund interest: 0.5% a month runs from 1 April only if you file on time; on a late return it runs only from the date you file (244A; 437).
• No prosecution: once a belated return is filed, you cannot be prosecuted for not filing.

234A: interest for filing late (section 423)

1% a month on the tax still unpaid on the due date, from the day after the due date to the day you file. Part of a month counts as a full month. "Unpaid" means tax after TDS, TCS, advance tax and self-assessment tax paid on or before the due date (CBDT Circular 2/2015), rounded down to the nearest ₹100. If you paid all your tax by the due date, there is no 234A even if the return is late.

Example. Ravi's tax for FY 2025-26 is ₹93,600 (taxable income ₹14 lakh, new regime, with cess). TDS was ₹80,000 and he paid no advance tax, so ₹13,600 is unpaid. His due date is 31 July 2026 and he files on 15 November 2026: 1 August to 15 November is 4 months (November counts in full). 234A = ₹13,600 × 1% × 4 = ₹544. With a 31 August due date (business, no audit), ₹8,400 unpaid and filing on 3 December 2026 gives 4 months (1 September to 3 December): ₹336.

234B: interest for short advance tax (section 424)

If your tax after TDS is ₹10,000 or more, you must pay advance tax during the year. If you paid less than 90% of it by 31 March, 1% a month is charged on the shortfall from 1 April after the year (1 April 2026 for FY 2025-26; 1 April 2027 for tax year 2026-27) until you pay, usually the day you file. It runs even if you file on time. Residents aged 60 or more with no business income need not pay advance tax, so they pay no 234B or 234C.

Example. Ravi: ₹13,600 × 1% × 8 months (1 April to 15 November 2026) = ₹1,088. Had he filed and paid on 31 July, it would have been 4 months, ₹544.

234C: interest for late advance-tax instalments (section 425)

Advance tax is due in four parts: 15% by 15 June, 45% by 15 September, 75% by 15 December and 100% by 15 March. On each shortfall you pay 3% for the first three dates and 1% for March. There is no June interest if you paid at least 12%, and no September interest if you paid at least 36%. Presumptive business or profession (44AD/44ADA) has one date only: 100% by 15 March, with 1% on the shortfall. 234C does not depend on when you file.

When an instalment date falls on a Sunday or a bank holiday (15 June 2025 and 15 March 2026 were Sundays), a payment on the next working day is generally treated as paid on time, and the calculator counts it that way. This is not yet confirmed: see Not yet settled.

Example. Ravi paid no advance tax. June: 15% of ₹13,600 is ₹2,040, taken as ₹2,000 × 3% = ₹60. September: ₹6,120, taken as ₹6,100 × 3% = ₹183. December: ₹10,200 × 3% = ₹306. March: ₹13,600 × 1% = ₹136. 234C = ₹685.

What Ravi pays

Had he filed and paid by 31 July 2026, he would have paid ₹14,830: no 234A and no fee, 234B for 4 months (₹544) and the same ₹685 of 234C. Filing late cost him ₹6,090 more (₹20,920 − ₹14,830). Before rounding the difference is ₹6,088: ₹544 of 234A, ₹544 more of 234B and the ₹5,000 fee. Work out your own figures in the free income tax calculator.

After 31 December: updated return

After 31 December 2026, a return for FY 2025-26 can no longer be filed in the normal way. What is left is an updated return (ITR-U) (section 139(8A); 263(6) from tax year 2026-27), which you can file within 4 years. It only lets you pay more tax: you pay the tax, the 234A/B/C interest and the late fee, plus additional tax as a share of the tax and interest:

The years run from the end of the assessment year (FY 2025-26: 31 March 2027) or, under the 2025 Act, from the end of the financial year after the tax year (tax year 2026-27: 31 March 2028). If you file it in reply to a reassessment notice (section 148; 280), another 10% of tax and interest is added (Finance Act, 2026). The late fee is not part of the base for additional tax (140B; 267).

Example. Never filed for FY 2025-26, ₹50,000 tax unpaid, no advance tax, ITR-U filed on 10 June 2027: 234A for 11 months ₹5,500; 234B for 15 months ₹7,500; 234C ₹2,525; additional tax 25% × (₹50,000 + ₹15,525) = ₹16,381; late fee ₹5,000. Total ₹86,906, rounded to ₹86,910.

If you had already filed an original, belated or revised return, an updated return carries no 234A and no fresh late fee: only 234B and 234C on the extra tax, besides the additional tax.

An updated return cannot:

• show a loss, or a bigger loss (from the Finance Act, 2026 it may reduce a loss shown in a loss return filed on time);
• lower your tax, or claim or increase a refund;
• be filed twice for the same year;
• be filed after a search or survey, once prosecution has started, or while an assessment or reassessment for that year is pending or completed, except within the time a reassessment notice allows (with the extra 10%);
• bring back the old regime, a loss carry-forward or refund interest.

If tax is due back to you and you missed 31 December, an updated return cannot claim the refund. The only route is a request to the Income Tax Department to condone the delay (section 119(2)(b), CBDT Circular 11/2024).

If you never file

• Notice and best-judgment assessment: the department can ask you to file (section 142(1); 268) and then work out your income itself (section 144; 271). 234A interest keeps running until that assessment.
• Penalty: income assessed above the basic exemption limit is treated as under-reported: 50% of the tax on it, or 200% if the income was misreported, for example hidden or backed by false entries (270A; 439).
• Prosecution, only for wilful failure (276CC as substituted by the Finance Act, 2026; 479), by the tax that would have been evaded:
  • above ₹50 lakh: simple imprisonment up to 2 years, or fine, or both;
  • above ₹10 lakh up to ₹50 lakh: up to 6 months, or fine, or both;
  • otherwise: fine only.
  There is no prosecution if you file a belated return, or an updated return within its time, or if your tax after TDS, advance tax and self-assessment tax is ₹10,000 or less.

Revised return: until 31 March

Found a mistake after filing? File a revised return. The Finance Act, 2026 gave three more months:

• FY 2025-26: until 31 March 2027 (it was 31 December 2026). Free up to 31 December 2026; from 1 January to 31 March 2027 a fee of ₹1,000 (total income up to ₹5 lakh) or ₹5,000 under the new section 234-I (section 139(5)).
• Tax year 2026-27: until 31 March 2028, free up to 31 December 2027 and the same fee after that (263(5); 428(b)).

A belated return can also be revised, but revising it does not bring back the old regime. Revision also stops once the assessment for the year is completed.

Old and new section numbers

FY 2025-26 returns, filed in 2026, still follow the Income-tax Act, 1961 (section 536 of the 2025 Act keeps it for earlier years). Tax year 2026-27 returns, filed in 2027, follow the Income-tax Act, 2025. The interest rates and fee amounts did not change; the section numbers did.

Key dates

FY 2025-26 (assessment year 2026-27)

Tax year 2026-27

Not yet settled

These points are not yet confirmed by CBDT or the e-filing portal. The figures on this page follow the reading given; check with your CA if one of them matters to you.

• Audit cases, FY 2025-26: whether 234A and the late fee start after 21 November (most likely) or after 31 October 2026, and whether a month then runs from 22 November to 21 December or by calendar month. Paying the tax by 31 October 2026 avoids the question.
• Form 10-IEA: whether its deadline also moved to 21 November 2026 for audit cases, and whether the old regime still applies when Form 10-IEA was filed in time but the return is late. File Form 10-IEA by 31 October to be safe.
• ₹4 lakh filing limit: that the new regime's ₹4 lakh is the limit for having to file is widely used, but no official FAQ states it.
• Revised-return fee (234-I): the section says "from the end of the relevant assessment year"; the e-filing portal charges the fee on revisions filed after 31 December 2026, and this page follows the portal.
• Updated return in January to March 2027: whether one can be filed for FY 2025-26 before 1 April 2027, while revised returns are still allowed, is not clear.
• Income-tax Act, 2025: section 423 does not itself say "part of a month" (Rule 269 and the department's FAQ do); the wording of the 12% and 36% safe harbours in section 425(2); and how the portal will apply the old-regime lock to 2027 returns.
• Working details: the 4% cess is taken into the interest base, as the portal does; each interest amount is shown in rupees and only the total is rounded to ₹10; and whether a payment on the next working day counts as on time when an advance-tax date falls on a Sunday or bank holiday (this page and the calculator assume it does).
• Fee and refund: whether the late fee can be adjusted against a refund in the return instead of being paid by challan.

Work out your figures

The free income tax calculator works out your tax under both regimes, then the interest and late fee for the date you file. You choose the due date it uses: the official date, the extended date (selected for you when there is one), or another date if CBDT extends again.

Income tax and GST on your phone: the BooksOn HSN appFree · no ads · works offline · old vs new regime with a PDF report · advance tax plan · since version 1.0.4, the interest and late fee for your filing date, with the due date you choose · reminders before advance-tax and GST due dates · English, हिन्दी, தமிழ்.

Official sources

• Income-tax Act, 1961 (FY 2025-26): section 139 (due dates; belated, revised and updated returns), 234A, 234B, 234C, 234F, 234-I, 140B, 115BAC, 244A, 270A, 276CC; Rule 119A, Rule 12AB.
• Income-tax Act, 2025 (tax year 2026-27): section 263, 267, 423, 424, 425, 428, 437, 439, 479; Income-tax Rules, 2026: Rule 163, Rule 269.
• CBDT Circular 07/2026 dated 28 September 2026 and the press release: audit-case due date extended to 21 November 2026.
• FAQs on interest under sections 423, 424, 425 and 426, Income Tax Department.
• Memorandum explaining the Finance Bill, 2026: the 31 August due date, the 12-month revised return and the new prosecution limits.
• Tax calendar, Income Tax Department.
• ITR-1 validation rules, AY 2026-27: old regime after the due date, and the 234-I fee.

Questions

See also: Income tax calculator: old vs new regime · GST calculator

Reference only, not tax advice: confirm with the Income-tax Act and your CA before filing. Compiled from the official sources above as of October 2026; see Sources & disclaimer.