Many taxpayers who purchase or construct a residential house to claim exemption under Sections 54 or 54F are unaware that selling the house within the prescribed lock-in period can reverse the earlier tax benefit. This article explains how such a sale affects the computation of capital gains, highlights the different tax implications under the two provisions, and outlines the precautions taxpayers should take while filing their Income Tax Return (ITR) for Assessment Year (AY) 2026-27