Indexation Benefit
Indexation benefit is a tax provision that adjusts the original purchase cost of a capital asset for inflation using the Cost Inflation Index (CII), reducing the taxable capital gain when the asset is sold. Available under Section 48 of the Income Tax Act.
Understanding Indexation Benefit
Indexation accounts for the fact that inflation reduces the real value of money over time. Without it, a property bought for ₹50 lakh in 2001 and sold for ₹2 crore in 2026 would show ₹1.5 crore as capital gain — but inflation alone has roughly tripled prices over those 25 years, so much of that "gain" is just inflation, not real wealth creation.
The indexed cost = Original cost × (CII of sale year / CII of purchase year). The capital gain is then sale price minus indexed cost. This significantly reduces the taxable amount for long-held assets.
Why it matters
For owners of pre-2024 real estate, the grandfathering rule preserves indexation benefit if they elect it (sometimes saving lakhs in tax). For new investments and debt mutual funds (post-Budget 2024), indexation is gone — the flat 12.5% rate applies regardless of holding period or inflation. Tax planning for long-held assets requires running both scenarios to pick the optimal regime at sale time.
Example
A real estate property purchased in 2010-11 for ₹50 lakh (CII = 167) is sold in 2024-25 for ₹2 crore (CII = 363). Pre-Budget 2024, the indexed cost = ₹50 lakh × (363 / 167) = ₹1.09 crore. Capital gain = ₹2 crore − ₹1.09 crore = ₹91 lakh. LTCG at 20% = ₹18.2 lakh. Without indexation, the gain would be ₹1.5 crore and tax at 12.5% = ₹18.75 lakh — comparable. The grandfathering rule in Budget 2024 lets old real estate owners choose either indexed 20% or unindexed 12.5%, whichever is lower.
A real estate property purchased in 2010-11 for ₹50 lakh (CII = 167) is sold in 2024-25 for ₹2 crore (CII = 363). Pre-Budget 2024, the indexed cost = ₹50 lakh × (363 / 167) = ₹1.09 crore. Capital gain = ₹2 crore − ₹1.09 crore = ₹91 lakh. LTCG at 20% = ₹18.2 lakh. Without indexation, the gain would be ₹1.5 crore and tax at 12.5% = ₹18.75 lakh — comparable. The grandfathering rule in Budget 2024 lets old real estate owners choose either indexed 20% or unindexed 12.5%, whichever is lower.