With just one day left for filing belated and revised income tax returns (ITR), a significant number of taxpayers are caught in a race against time. The Income Tax Department has flagged mismatches in numerous original filings, prompting requests for revised returns. This has resulted in a backlog, leaving thousands of ITRs for the Assessment Year 2025-26 unprocessed, particularly those involving refund claims.
The Crucial December 31 Deadline
The final date to submit a revised ITR, December 31, is critical for taxpayers. However, a key disparity exists between the deadlines for filers and the tax authorities. While taxpayers lose the right to revise their returns after this date, the Centralised Processing Centre (CPC) has a much longer window. The CPC has until December 31, 2026, to process returns for this year.
Rohit Jain, Managing Partner at Singhania & Co., clarifies the rule: "Under Section 143(1) of the Income Tax Act, 1961, the CPC must process your return and send an intimation within 9 months from the end of the financial year in which the return is filed." This mismatch in timelines has caused widespread confusion, with many taxpayers incorrectly believing they can revise returns after December 31 if their original filing remains unprocessed.
Scale of the Processing Backlog
The scale of the pending work is substantial. According to a report by Moneycontrol, as of December 28, 2025, the income tax department is yet to process approximately 70 lakh (7 million) ITRs. For Assessment Year 2025-26, a total of 8.4 crore (84 million) returns have been filed, with about 7.8 crore already processed. The department's compliance messages and mismatch alerts have led to over 21 lakh (2.1 million) revised ITRs being filed this year.
Consequences of Missing the Deadline
Failing to file a revised ITR by the December 31 deadline closes that option permanently. Taxpayers do have an alternative, but it comes at a higher cost. They can file an Updated Return under Section 139(8A) for a period of up to four years from the end of the relevant assessment year. However, this route involves paying higher taxes and interest compared to a standard revised return. Crucially, an Updated Return cannot be used to claim a refund or to reduce an existing tax liability; it is only for declaring additional income and paying due tax.
The key takeaways for taxpayers are clear. The right to revise an ITR ends strictly on December 31, independent of whether the CPC has processed the original return. While the department has a lenient processing timeline, taxpayers face a firm, non-negotiable filing deadline. Missing it forces one into the more expensive Updated Return mechanism, which offers no benefit for those awaiting refunds.
