4 Key Income Tax Deadlines in December 2025: ITR Filing, TDS, Advance Tax and More

December is one of the most compliance-heavy months for taxpayers, with multiple Income Tax deadlines approaching in quick succession. Individuals, businesses, auditors and government departments must complete key filings, payments and submissions before the year ends to avoid penalties or delays.

Here are the four major tax deadlines that taxpayers must track closely this month.

December 10, 2025 — ITR Filing Deadline for Audited Taxpayers

December 10 is the extended due date for Income Tax Return filing for Assessment Year 2025–26 for all taxpayers whose accounts require audit. This includes corporate and non-corporate entities, partners of audited firms and individuals governed by Section 5A.
The original deadline of October 31 was extended, giving taxpayers additional time, but no further extension is expected.

December 15, 2025 — Advance Tax, TDS Compliance and Form Filings

Multiple tax filings and payments converge on December 15:

• Upload Form 27C for November
• Government offices must submit Form 24G for TDS/TCS paid without a challan
• Payment of the third instalment of Advance Tax for AY 2026–27
• Issue TDS certificates for October under Sections 194-IA, 194-IB, 194M and 194S
• Stock exchanges must file Form 3BB for client code changes made in November

This makes mid-December one of the busiest tax compliance windows of the year.

December 30, 2025 — TDS Statements and Client Code Reporting

Recognised associations must file their client code modification statements for the month of November by December 30.
Taxpayers who deducted TDS in November must also submit their TDS challan-cum-statement by this date, ensuring accurate reporting of all deductions.

December 31, 2025 — Final Deadline for Belated and Revised ITRs

The last and most critical deadline of the year is December 31.
This is the final opportunity to file belated or revised Income Tax Returns for AY 2025–26, provided the assessment is still pending.

Missing this date may lead to penalties, interest, loss of certain benefits and delays in refund processing.

Why December Is Crucial

With major filings falling back-to-back, early preparation is essential. Completing these tasks on time helps taxpayers avoid compliance lapses and ensures smooth closure of the financial calendar.