September 2026 income tax calendar: Key TDS, TCS, advance payment and audit deadlines you should know

September has several important income tax compliance deadlines for taxpayers, businesses, and other entities.

The month also brings a series of 30 September deadlines, mainly related to tax audits and audit reports. Taxpayers covered by these requirements should ensure that the relevant audit reports and forms are filed on time, especially where the income tax return is due on 31 October 2026.

Here are the key tax deadlines to watch out for in September 2026.

7 September: TDS and TCS payment deadline

Tax deducted or collected during August 2026 needs to be deposited with the government by 7 September.

• Who needs to comply: Persons or entities responsible for deducting tax at source (TDS) or collecting tax at source (TCS).
• Special rule for government offices: Where tax is deducted or collected by a government office, it must be credited to the central government on the same day if payment is made without producing an income tax challan.

14 September: TDS certificate for certain deductions

• Who needs to comply: Persons responsible for issuing the TDS certificate. Form 132 under the Income Tax Act, 2025 covers TDS deducted on rent, transfer of immovable property, commission, brokerage and transfer of virtual digital assets (VDAs).
• What is required: Taxpayers need to issue Form 132 for TDS deducted on these payments during July 2026.

15 September: Second instalment of advance tax

• Who needs to pay: Taxpayers liable to pay advance tax for Tax Year 2026-27.
• What is required: Pay the second instalment of advance tax by the due date. Advance tax allows taxpayers with significant tax liabilities to pay their tax in instalments during the year instead of paying the entire amount at the time of filing the return.

30 September: Major audit and reporting deadlines

The final day of September has several compliance requirements, largely meant for businesses, companies, trusts, specified funds, and other taxpayers subject to audit.

Tax audit under section 44AB

• Tax audit report under section 44AB of the Income Tax Act, 1961.
• Corporate and non-corporate taxpayers are required to file their income tax return by 31 October 2026 and are covered by tax audit provisions.
• A tax audit is an examination of a taxpayer's accounts by a chartered accountant to check whether the financial records comply with the income tax law.

Form 3CE

• Non-residents and foreign companies covered under section 44DA of the IT Act, 1961.
• File the audit report for the previous year 2025-26. The report provides details needed to verify income earned in India from specified royalty or technical-service arrangements.

Form 3CEA

• Taxpayers involved in a slump sale are taxable under section 50B of the IT Act, 1961. A slump sale refers to the transfer of an entire business undertaking for a lump-sum consideration rather than selling individual assets.

Forms 29B and 29C

• Form 29B: Companies covered by section 115JB of the IT Act, 1961 must furnish the report for computing book profits.
• Form 29C: Taxpayers other than companies covered by section 115JC must furnish the report for computing adjusted total income and alternate minimum tax (AMT).

Other audit reports

By 30 September, certain eligible entities must also file prescribed audit reports under the Income Tax Act, 1961, where their ITR is due on or before 31 October.

• Form 66: Tonnage tax companies under section 115VW.
• Form 10-IL: Specified funds that are investment divisions of offshore banking units, for claiming exemption under section 10(4D).
• Forms 10B/10BB: Applicable funds, trusts, institutions, universities, educational institutions, hospitals and medical institutions.

Disclaimer: This is only for informational and educational purposes. Please consult a qualified expert for the latest laws and regulations.