Can we switch regime while filing ITR-U?

No, not eligible.                      

Switching tax regime while filing ITR-U is one of the most common questions during ITR season.

Short answer: NO, you generally cannot switch tax regime via ITR-U.

Here is why:

ITR-U (Updated Return under Section 139(8A)) allows you to CORRECT errors or ADD income that was omitted in original/revised return. The tax regime election (new vs old) was made at the time of original filing and is a deliberate position, not an error.

Key points:

1. Tax regime is not an "error" that ITR-U corrects. It is a deliberate election.
2. CBDT treats regime switching as a material change, not a correction.
3. For salaried individuals: regime was locked at the time of TDS declaration to employer (Form 12BAA/declaration).
4. For business income (Section 44AD/44ADA): regime choice is sticky until formally opted out.

The one exception: if you NEVER filed any return (original or belated) and are filing ITR-U as your FIRST return for that AY, regime selection is available.

Practical suggestion: If you want to switch regime for AY 2026-27, check if you still have time to file a revised return (December 31, 2026 is the deadline for AY 2026-27). Revised return allows regime change; ITR-U does not.

For a full breakdown of what ITR-U can and cannot correct (income categories, penalties, and the 48-month window), see: https://taxgarden.in/blog/itr-u-updated-return-48-month-window-guide