Capital Gains Tax on Under-Construction Property: A Seller's Guide

Selling a flat before the builder hands it over feels like a simple transaction. The price has gone up, the buyer is ready, and you want to exit. But the tax treatment of that sale is anything but simple. Capital gains tax under construction property India follows rules that have changed meaningfully after Budget 2024 and that treat your holding period, your cost of acquisition, and your reinvestment options differently from a completed property sale. Getting this wrong does not just mean a surprise tax bill. It can mean a significantly larger one than you expected, arriving at exactly the moment you thought you were ahead.

When you sell your rights in an under-construction flat, you are technically selling a right to receive a property rather than the property itself. But the Income Tax Act treats this transaction as a transfer of a capital asset, which means capital gains tax applies in the same way it would on a completed flat. The gain is calculated as the difference between your sale consideration and your cost of acquisition, which is the total amount you paid to the developer up to the date of sale including the booking amount, all instalment payments, and any other charges that form part of the registered agreement.

Brokerage paid to facilitate the sale can be deducted from the sale consideration before arriving at the net gain. Stamp duty paid at the time of original booking can be added to the cost. These two adjustments together can reduce your taxable gain meaningfully, and both are legitimate and straightforward to claim.

Whether your gain is classified as LTCG or STCG on under construction property depends on how long you held the asset before selling. For immovable property in India, the threshold is 24 months. Hold for less than 24 months and the gain is short term, taxed at your applicable income tax slab rate. Hold for 24 months or more and the gain is long term, subject to a flat 12.5% rate after Budget 2024 removed the indexation benefit for most property sales.

The holding period starts from the date of the original allotment letter or the booking agreement, not from the date of possession. This matters enormously for under-construction buyers who booked early and are selling mid-construction. Someone who booked in January 2022 and sells in March 2026 has held for over 24 months regardless of the fact that the flat is still being built.

This is where sellers of older under-construction bookings need to pay close attention. Until July 2024, long term capital gains on property were taxed at 20% with indexation, meaning your cost of acquisition was adjusted upward using the Cost Inflation Index to account for inflation over the holding period. That adjustment often reduced the taxable gain substantially, particularly for properties held for five or more years.

Budget 2024 changed this to a flat LTCG rate of 12.5% without indexation for property sold after July 23, 2024. For recently purchased properties held for short periods, the new rate is often better. For properties purchased several years ago where the inflation adjustment would have been large, the removal of indexation can actually increase the tax outgo despite the lower headline rate.

There is a partial relief available for properties purchased before July 23, 2024. Sellers can choose between the old 20% with indexation regime and the new 12.5% without indexation and apply whichever produces a lower tax liability. Do not file without calculating both. The difference can run into lakhs.

Under-construction properties are almost always paid in instalments linked to construction milestones. Every instalment you paid to the developer, from booking amount to the final pre-possession payment, forms part of your cost of acquisition. Home loan interest paid during the construction period, however, does not form part of the cost for capital gains purposes. It may be claimed separately under Section 24(b) subject to conditions but it cannot be added to the property's cost base for the purpose of calculating your gain.

Keep every payment receipt, bank transfer record, and demand letter from the developer. The documentation burden at the time of filing is directly proportional to how organised your payment records are.

If you are reinvesting the sale proceeds, two sections of the Income Tax Act offer exemptions that can reduce or eliminate the capital gains tax property India liability. Section 54 allows you to claim an exemption if you purchase or construct another residential property within the specified time limits: purchase within one year before or two years after the sale, or construct within three years. The exemption is capped at Rs 10 crore for gains arising from April 1, 2023 onward.

Section 54EC allows you to invest the capital gains amount in specified bonds issued by NHAI or REC within six months of the sale, up to Rs 50 lakh, to claim exemption. These bonds carry a five-year lock-in and earn a modest fixed interest rate. They are a useful option for sellers who do not want to reinvest in another property immediately.

Capital gains tax on under construction property sale in India depends on holding period, acquisition cost including all instalments, and the post-Budget 2024 regime choice between 12.5% without indexation and 20% with indexation for pre-July 2024 purchases. LTCG applies after 24 months from booking date, not possession. Reinvestment under Section 54 or Section 54EC can reduce or eliminate the tax liability. Calculate both regimes, document every payment carefully, and consult a tax professional before executing any under-construction property sale transaction.