The Budget 2024 transitional choice, worked example: Property bought 2015 for ₹40L. Sold 2025 for ₹1Cr. Holding: 10 years. OPTION A (12.5% no indexation): LTCG = ₹1Cr − ₹40L = ₹60L. Tax = ₹7.5L. OPTION B (20% with CII indexation): CII 2015 = 254, CII 2025 = 363 (approx). Indexed cost = ₹40L × 363/254 = ₹57.1L. LTCG = ₹1Cr − ₹57.1L = ₹42.9L. Tax = 20% × ₹42.9L = ₹8.58L. OPTION A (12.5%) is LOWER. Choose Option A. When Option B (20% with indexation) wins: If property was bought in 1995-2005 era: very high indexation benefit. Example: bought 1998 for ₹8L, sold 2025 for ₹60L. CII 1998 = 351, CII 2025 = 363. Wait, CII doesn't go that far back directly. For very old properties: use FMV as on April 1, 2001 as the cost (instead of actual cost). This resets basis to 2001 FMV which is much higher than 1998 cost. Then index from 2001.