Income Tax Calendar 2026 Flags Eight Deadlines from August to December
An income-tax calendar published on 16 August 2026 listed eight deadlines falling between August and December 2026. Most of them relate to Assessment Year (AY) 2026-27, which covers income of 2025-26 and is still governed by the Income-tax Act, 1961, while the advance tax dates relate to the current year. This report checks each date against the Income Tax Department's own guidance and sets out who each one applies to.
The dates, verified
| Date | What is due | Who it applies to |
|---|---|---|
| 31 August 2026 | Income tax return for AY 2026-27 | Non-audit cases for which the due date is 31 August (others in the non-audit category had 31 July 2026) |
| 15 September 2026 | Second advance tax instalment: at least 45% of advance tax | Every person liable to pay advance tax |
| 30 September 2026 | Tax audit report for AY 2026-27 | Audit cases whose return is due on 31 October 2026 |
| 31 October 2026 | Income tax return for AY 2026-27 | Audit cases (other than transfer pricing cases) |
| 31 October 2026 | Tax audit report | Transfer pricing cases whose return is due on 30 November 2026 |
| 30 November 2026 | Income tax return for AY 2026-27 | Transfer pricing cases |
| 15 December 2026 | Third advance tax instalment: at least 75% of advance tax | Every person liable to pay advance tax |
| 31 December 2026 | Belated return for AY 2026-27 | Anyone who missed the original due date, if assessment is not completed earlier |
The calendar also listed a quarterly TDS statement date for the July to September quarter. That date is not covered by the Department pages checked for this report, so deductors should confirm the due date and form for their statement on the e-filing and TRACES portals.
Return due dates for AY 2026-27
The Department's Income Tax Returns help page says returns for AY 2026-27 are filed in the old ITR forms on the e-filing portal, with 31 July 2026 or 31 August 2026 as the due date for non-audit cases. It confirms that a belated return for AY 2026-27 may be furnished on or before 31 December 2026, or before the assessment is completed, whichever is earlier. A revised return for AY 2026-27 is governed by Section 139(5) of the 1961 Act and can be filed before the end of the relevant assessment year, that is, before 31 March 2027.
Tax audit report
The same help page states that the tax audit report for AY 2026-27 is due one month before the return due date: 30 September 2026 where the return is due on 31 October 2026, and 31 October 2026 for transfer pricing cases where the return is due on 30 November 2026. The Department's Form No. 26 FAQs add that Forms 3CA, 3CB and 3CD continue for audits of previous years relevant to assessment years up to 2026-27. The new Form No. 26 applies only from tax year 2026-27.
Advance tax
The Department's advance tax FAQ lists four instalments: at least 15% by 15 June, at least 45% by 15 September, at least 75% by 15 December and 100% by 15 March. Tax paid on or before 31 March is also treated as advance tax for the financial year. A shortfall against these cumulative percentages attracts interest, so taxpayers who missed the 15 September mark should top up before 15 December.
What to do now
- Audit clients whose return is due on 31 October: the audit report is due on 30 September 2026, so upload and acceptance on the portal should be completed before that date.
- Taxpayers who missed the July or August due date: a belated return is possible until 31 December 2026.
- Anyone who finds an error in a filed AY 2026-27 return can revise it before 31 March 2027.
- Estimate current-year income now and plan the 15 December instalment to reach the 75% level.
Updated on 27 September 2026: replaced general commentary with the calendar dates, checked against the Income Tax Department's help pages and FAQs, and added the revised return time limit and the audit form position.
