When a residential house is sold, most taxpayers are aware that the resulting capital gain is chargeable to tax under Section 45 of the Income-Tax Act, 1961 in the assessment year relevant to the financial year in which the sale takes place. They also generally know that the gain is treated as long-term or short-term depending on the period of holding. In the case of a residential house, the gain is regarded as long-term if the house is sold after being held for more than 24 months; otherwise, it is treated as short-term.However, many taxpayers overlook an equally important aspect.When a residential house has been purchased or constructed for claiming exemption under Section 54 in respect of long-term capital gain arising from the sale of a residential house, or under Section 54F in respect of long-term capital gain arising from the sale of any other long-term capital asset, its subsequent sale is subject to specific statutory conditions. Ignoring these conditions can result in incorrect computation of capital gains and may ultimately lead to scrutiny or reassessment proceedings, additional tax demands, interest, penalties, and avoidable litigation.Capital gain computation in a normal situationIn a normal case, capital gains on the sale of a residential house are computed by deducting the following from the full value of consideration received or accruing as a result of the sale:Cost of acquisition;Cost of improvement, if any; andExpenditure incurred wholly and exclusively in connection with the sale.However, this normal method of computation undergoes a significant change when the residential house being sold had earlier been purchased or constructed for claiming exemption from long-term capital gains under Section 54 or Section 54F. The manner in which the earlier exemption is withdrawn differs under the two provisions and has a direct bearing on the computation of capital gains arising from the subsequent sale of that house.Also read: Bengaluru landowner sells 17 apartments, earns Rs 11.8 crore LTCG, pays no tax; I-T dept sends notices; he contests and wins in ITAT BangaloreSection 54 alters the computation of capital gainsOne of the important conditions for claiming exemption under Section 54 is that, if the residential house purchased or constructed for claiming the exemption is sold within three years from the date of its purchase or construction, the exemption is effectively withdrawn while computing the capital gain arising from the sale of that house.The manner in which the exemption is withdrawn depends upon the relationship between the amount of capital gain exempted earlier and the cost of acquisition of the residential house that is subsequently sold within three years.Also read: NRI sells his Bangalore property for Rs 2.63 crore, declares Rs 16.33 lakh LTCG, gets tax notice; he fights and wins partial relief from ITAT for this reasonSituation 1: Cost of the new residential house is less than the capital gainWhere the cost of the new residential house purchased for claiming exemption under Section 54 is less than the amount of long-term capital gain arising from the sale of the old residential house, the cost of acquisition of the new residential house is taken as nil while computing the capital gain on its sale within three years from the date of its purchase or construction.ExampleMr. A sold his old residential house and earned a long-term capital gain of Rs 60 lakh. He purchased a new residential house for ?40 lakh and claimed exemption of Rs 40 lakh under Section 54.If he sells the new residential house within three years for Rs 55 lakh, the cost of acquisition for the purpose of computing capital gains will be taken as nil. Consequently, the taxable capital gain will be Rs 55 lakh, instead of Rs 15 lakh, which would have been taxable under the normal provisions.Situation 2: Cost of the new residential house is equal to or exceeds the capital gainWhere the cost of the new residential house purchased for claiming exemption under Section 54 is equal to or exceeds the amount of long-term capital gain arising from the sale of the old residential house, the cost of acquisition of the new residential house is reduced by the amount of exemption claimed while computing the capital gain on its sale within three years from the date of its purchase or construction.ExampleMr. B sold his old residential house and earned a long-term capital gain of Rs 60 lakh. He purchased a new residential house for ?80 lakh and claimed exemption of Rs 60 lakh under Section 54.If he sells the new residential house within three years for Rs 1 crore, the cost of acquisition for the purpose of computing capital gains will be reduced from Rs 80 lakh to Rs 20 lakh (Rs 80 lakh Rs 60 lakh). Accordingly, the taxable capital gain will be Rs 80 lakh, instead of Rs 20 lakh, which would have arisen under the normal provisions.In both the above examples, it is assumed that the sale consideration is equal to or exceeds the stamp duty value. Accordingly, Section 50C does not alter the full value of consideration adopted for computing the capital gain.Impact compared with the normal method of computation Particulars Situation 1 Situation 2 Capital gain under normal provisions Rs 15,00,000 Rs 20,00,000 Capital gain after applying Section 54 Rs 55,00,000 Rs 80,00,000 Earlier exemption withdrawn Rs 40,00,000 Rs 60,00,000 The above examples demonstrate that under Section 54, the earlier exemption is not brought to tax separately. Instead, the tax benefit is effectively withdrawn by reducing the cost of acquisition of the new residential house or, where applicable, by treating the cost as nil.Section 54F withdraws the earlier exemptionSection 54F adopts a completely different mechanism from Section 54.Where the residential house purchased or constructed for claiming exemption under Section 54F is sold within three years from the date of its purchase or construction, the amount of long-term capital gain that was earlier exempt under Section 54F is deemed to be the long-term capital gain of the assessment year relevant to the financial year in which the new residential house is sold.Unlike Section 54, there is no reduction in the cost of acquisition of the new residential house. Instead, the exemption allowed earlier is brought to tax separately in the year of sale.ExampleMr C sold a plot of land for Rs 1 crore (at a price higher than the stamp duty value). After deducting the cost of acquisition of Rs 40 lakh, his long-term capital gain amounted to Rs 60 lakh.He invested the entire net consideration of Rs 1 crore (i.e., the sale consideration as reduced by expenses incurred wholly and exclusively in connection with the transfer) in a residential house and claimed exemption of the entire capital gain of Rs 60 lakh under Section 54F.He sold the residential house within three years of its purchase.The tax consequences are as follows:The Rs 60 lakh exempted earlier under Section 54F becomes taxable as long-term capital gain under Section 54F(3) in the assessment year relevant to the financial year in which the new residential house is sold.In addition, the capital gain arising from the sale of the residential house is computed separately under the normal provisions, based on its actual cost of acquisition, cost of improvement (if any), transfer expenses, and Fair Market Value.Thus, two separate capital gain computations may arise in the same assessment year:1. Withdrawal of the earlier exemption under Section 54F(3); and2. Capital gain arising from the sale of the new residential house under the normal provisions of the Act.Difference in exemption withdrawal: At a glance Particulars Section 54 Section 54F Is the earlier exemption withdrawn? Yes. Yes. How is the exemption withdrawn? By reducing the cost of acquisition of the new residential house or treating it as Nil, as the case may be By taxing the earlier exempt capital gain separately. Capital gain computation on sale of new residential house Single computation—capital gain is computed by adopting the reduced cost (or Nil cost, as the case may be). Two separate computations—(i) the earlier exempt capital gain is taxed, and (ii) capital gain on the sale of the residential house is computed separately under the normal provisions. What should taxpayers do now?Taxpayers who sold a residential house during FY 2025-26 that had earlier been purchased or constructed for claiming exemption under Section 54 or Section 54F should carefully verify the following before filing their Income Tax Return (ITR) for AY 2026-27:Whether the residential house was sold within three years from the date of its purchase or construction.Whether the exemption claimed earlier under Section 54 or Section 54F has been correctly dealt with in accordance with the applicable provisions.Whether the capital gain has been computed correctly after giving effect to these provisions.Whether the resulting capital gain has been correctly reported in the ITR .Taxpayers who have already filed their ITR should verify whether the capital gain has been computed and reported correctly. If any error or omission is noticed, they should consider filing a revised return within the prescribed time to rectify the mistake.In case of similar mistakes relating to earlier assessment years, taxpayers may evaluate whether they are eligible to file an updated return under Section 139(8A), subject to the prescribed conditions and time limits.Correct the mistake before it becomes a tax disputeAs discussed, the law adopts two different mechanisms for withdrawing the earlier tax benefit. Under Section 54, the cost of acquisition of the new residential house is adjusted based on capital gain exemption claimed, whereas under Section 54F, the capital gain that was exempt earlier is brought to tax separately. Ignoring these provisions can result in incorrect computation and reporting of capital gains.Such omissions are increasingly likely to be detected because the Income Tax Department already has the particulars of the residential house in respect of which exemption under Section 54 or Section 54F was claimed, as these details are disclosed in the income tax return for the relevant assessment year. The subsequent sale of the same property can therefore be readily correlated with the earlier claim, making incorrect reporting easier to identify during the processing of the return or in subsequent proceedings.Before filing your Income Tax Return (ITR), carefully review all property transactions undertaken during the year and verify whether the sale of any residential house purchased or constructed for claiming exemption under Section 54 or Section 54F requires a corresponding adjustment in the computation of capital gains.Accurate reporting at the time of filing the income tax return or timely correction of any error by filing a revised return is the simplest and most effective way to avoid unnecessary tax demands and disputes. Once under-reporting of capital gains is detected by the Income Tax Department, rectifying the mistake can become far more expensive in terms of additional tax, interest, penalties, time, and other compliance costs.The author, O.P. Yadav, is a former IRS officer with over 36 years of experience in tax administration, education, and training. He is presently associated with Prosperr.io as Tax Evangelist. The views expressed are personal.(Disclaimer: The opinions expressed in this column are that of the writer. The facts and opinions expressed here do not reflect the views of www.economictimes.com.)