September Tax Deadlines: What Taxpayers Need to Know

September brings a fresh set of tax compliance deadlines for taxpayers, businesses, and other entities. Following the August 31 income-tax return deadline for many taxpayers, the focus now shifts to TDS and TCS payments, advance tax instalments, and tax audit reports. Missing these dates can result in interest, penalties, or compliance complications, as reported by Business Standard and Livemint.

TDS and TCS Payment: September 7

The first major deadline falls on September 7. Tax deducted or collected during August 2026 must generally be deposited with the central government by this date. This applies to businesses, employers, and other deductors or collectors required to deduct TDS or collect TCS.

A special rule applies to 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, as reported by Livemint. Business Standard adds that this date is also relevant for uploading certain declarations received during August under the new income-tax rules.

TDS Certificate Form 132: September 14

September 14 is the deadline for issuing the prescribed TDS certificate, Form 132, for tax deducted during July 2026. According to Livemint, 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).

Business Standard notes that these certificates are important for employees and other taxpayers whose income has been subject to TDS, as they help verify whether the tax deducted has been correctly reported against their tax records. Any mismatch between the tax deducted and the tax reflected in the taxpayer's records can create problems while filing or reconciling an income-tax return.

Advance Tax Second Instalment: September 15

For taxpayers liable to pay advance tax, September 15 is perhaps the most important date in the month, according to Business Standard. The second instalment of advance tax for Tax Year 2026-27 is due on this date.

Business Standard further explains that for taxpayers following the regular instalment schedule, cumulative advance tax payment should reach at least 45 per cent of the estimated annual liability by this date. Advance tax applies when the estimated tax payable for the year is at least Rs 10,000, as reported by Business Standard. Livemint describes advance tax as allowing 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.

Tax Audit and Other Reporting Deadlines: September 30

September 30 is a major deadline for tax audit reports and various other compliance requirements. The tax audit report under section 44AB of the Income Tax Act, 1961 is due by this date, as reported by both Business Standard and Livemint.

Livemint details a range of other audit reports and forms due on September 30, including:

  • Form 3CE for non-residents and foreign companies under section 44DA
  • Form 3CEA for taxpayers involved in a slump sale under section 50B
  • Forms 29B and 29C for companies and other taxpayers under sections 115JB and 115JC
  • Other audit reports including tonnage tax companies under section 115JB and Form 10B/10BB for trusts and institutions

Business Standard notes that September 30 also covers certain other reporting requirements, including challan-cum-statement for specified TDS.

Livemint adds that income tax returns are due on 31 October 2026 for taxpayers covered by the September 30 tax audit deadline. Business Standard cautions that missing these dates can result in interest, penalties, or compliance complications, urging taxpayers to mark the relevant dates based on the nature of their income and tax obligations.