Home loan interest can cut your capital gains tax when you sell — but only if you never claimed it.
Every year you didn’t claim your home loan interest under Section 24(b) — because you’d opted for the new tax regime, because the property was under construction, or because your accountant simply missed it — that interest didn’t vanish. It sat there. And when you eventually sell the property, it can resurface as a deduction against your capital gains.
Most sellers never make this connection. They calculate their gain the way their bank statement suggests — sale price minus purchase price — and pay tax on a number that’s larger than it has to be. A recent tribunal order out of Bengaluru is a useful reminder of exactly how much is on the table, and exactly how narrow the window is to claim it.
The rule in one line
Interest you paid on a home loan but never deducted under Section 24(b) or Chapter VI-A can be added to your property’s cost of acquisition under Section 48, when you compute long-term capital gains on the sale. Interest you already claimed cannot be added a second time — that door is now permanently shut by statute.
Two sections of the Act, and the gap between them
Section 24(b) is the deduction most borrowers already know: interest paid on a home loan, set off every year against income from house property. For a self-occupied home under the old tax regime, it’s capped at ₹2 lakh a year. Under the new regime, it isn’t available at all for a self-occupied property — only for a let-out one. That single detail is why so many people carry years of “unclaimed” interest without realising it: anyone who moved to the new regime, or whose flat was empty of tenants and just sitting under the old ₹2 lakh cap while actual interest ran higher, has interest that never got used.
Section 48 is a different animal — it governs how you arrive at your capital gain when you sell, by letting you subtract the cost of acquisition and improvement from the sale price. For years, tribunals allowed unclaimed home loan interest to count as part of that cost, on the reasoning that money never deducted elsewhere shouldn’t be denied twice over. The Finance Act 2023 wrote this into the statute directly, adding a proviso to Section 48 that’s been in force since AY 2024-25: cost of acquisition cannot include interest already claimed under 24(b) or Chapter VI-A. Everything else — interest that was never claimed — still qualifies.
There’s also a piece worth flagging that rarely gets attention: pre-construction interest. If you paid EMIs before possession and never claimed the deferred deduction in the five instalments Section 24(b) allows after handover, that too counts as unclaimed and can be added at sale.
The case that put this on the record
₹1.13 lakh saved on the interest alone. Unrecovered builder deposits stack on top.
On the rate: for property bought before 23 July 2024 and sold after, resident individuals and HUFs can pick the lower of 12.5% without indexation or 20% with indexation. Non-residents don’t get that choice — they pay 12.5% without indexation. Either way, adding interest to cost lowers the base the tax is calculated on.
Selling to buy your next home? Reinvesting the gain under Section 54 can wipe out the tax entirely — and Butter Money can size your next loan around the numbers. Run your eligibility now, free and with no impact on your score. [Check eligibility →]
Five ways to lose the claim
- You already claimed it. Once interest has been deducted under 24(b) in any year, it’s spent — there’s no double-dipping, and since AY 2024-25 the law says so explicitly.
- You can’t prove it was unclaimed. “I never claimed it” isn’t a fact until it’s backed by returns and interest certificates. Without that trail, an assessing officer has every reason to disallow the claim.
- You treat the tribunal order as a guarantee. It’s persuasive, not binding on every officer who reviews your file. Build in the possibility of a query — or an appeal — even with clean documentation.
- Your other costs aren’t tied cleanly to the transfer. Section 48 only allows expenses incurred wholly and exclusively for the sale. A vague “selling expenses” line invites exactly the scrutiny the travel claim got in the Bengaluru case.
- You’re selling as an NRI. TDS gets deducted at higher rates at source, and the 20%-with-indexation option isn’t available to you. If you’re selling from abroad, get a lower or nil TDS certificate under Section 197 sorted before the sale closes, not after.
A three-phase checklist before you file
Before you list the property
- Line up your ITRs for every year you held the loan.
- Get a single, year-wise interest certificate from your lender spanning the full loan tenure — not a lump-sum figure.
- NRI? Get your Section 197 lower/nil TDS application moving now — the processing time alone is reason enough to start early.
While you compute the gain
- Break the interest down year by year and split what you actually claimed under 24(b) from what you didn’t.
- Only the unclaimed interest adds to your cost of acquisition — the full interest outgo doesn’t qualify.
- Factor in mandatory, non-refundable builder deposits (maintenance, electricity, water) as part of your cost base.
- Track genuine transfer costs separately — brokerage, legal fees, stamp duty on sale — with paperwork to back each one.
Before you file
- Get a CA to reconcile the claim against your interest certificates and ITRs before it touches your return.
- Documentation doesn’t guarantee the claim won’t be questioned — go in knowing your fallback position.
Summary
The takeaway is narrow and useful: unclaimed home loan interest can lower your capital gains tax, documentation protects the claim, and if you already took the Section 24(b) deduction, the door is closed. Indian homeownership carries more tax levers than anyone tells you upfront — knowing which one applies to you, and proving it, is what turns a tribunal headline into money you keep.
General information, not tax advice. Capital gains treatment depends on your specific facts — consult a chartered accountant before filing.
Frequently asked questions
Q1. Can I add home loan interest to the cost of acquisition when selling? Yes — if you never claimed it under Section 24(b) or Chapter VIA. Unclaimed interest adds to your cost under Section 48 and lowers your long-term gain. Interest already claimed can’t be added again.
Q2. What if I already claimed it under 24(b)? Then you can’t add it. Since AY 2024-25, a proviso to Section 48 explicitly bars including interest already claimed under 24(b) or Chapter VIA.
Q3. Does this still apply after the 2024 tax changes? Yes. The Finance Act 2023 proviso (AY 2024-25) confirmed only unclaimed interest can be added. Separately, LTCG on property sold on/after 23 July 2024 is taxed at 12.5% without indexation — with a 20%-with-indexation option only for resident individuals/HUFs on property bought before that date.
Q4. What documents prove the interest was never claimed? Past ITRs showing no 24(b) claim, year-wise lender interest certificates, and the loan statement of account. The Bengaluru seller won on his earlier returns.
Q5. Can NRIs claim this? Yes — the Bengaluru case was an NRI. But NRIs face higher TDS on the sale and no 20%-with-indexation option, so a lower/nil TDS certificate under Section 197 and full documentation matter even more.
Q6. Are builder deposits (maintenance, electricity, water) part of the cost? They can be, if they were mandatory for possession and not recovered from your buyer. The tribunal allowed a one-time maintenance deposit and utility deposits, eligible for indexation.
Q7. Are travel/selling expenses deductible under Section 48? Only if incurred wholly and exclusively for the transfer, and provable. In the Bengaluru case, the travel claim was sent back for verification, not allowed outright.