These taxpayers can't switch between old and new regimes every year: Know Form 10-IEA rules, deadline and filing process

Taxpayers with business or professional income cannot switch between the old and new tax regimes every year. Form 10-IEA is required for the switch, with restrictions on re-entering the old regime. Here's what taxpayers filing ITR-3 and ITR-4 need to know for AY 2026-27.