Sold Property in FY26? Recompute Your Advance Tax Now

The Cost Inflation Index for FY 2026-27 was released late, after the June advance tax deadline. If you sold property bought before July 23, 2024, you may have underpaid advance tax and need to fix it now to avoid interest penalties.

Here's what happened: The government notified the Cost Inflation Index for FY 2026-27 after the June 15 advance tax deadline, leaving property sellers without official figures to compute capital gains accurately.. Sellers of property acquired before July 23, 2024 can use indexation benefits to reduce their long-term capital gains tax — but only if they used the correct CII figure.. Anyone who estimated advance tax without the final CII number may have overpaid or underpaid, triggering either a refund opportunity or an interest liability under Section 234C..

What you should do: Recalculate your long-term capital gains now using the officially notified CII for FY 2026-27 and compare it against what you paid in June's advance tax instalment.. If you underpaid, top up the shortfall in the September 15 advance tax instalment to avoid accumulating 1% per month interest under Section 234B and 234C.. If you overpaid advance tax due to a higher capital gains estimate, file your ITR accurately to claim the refund — do not skip filing thinking it will auto-adjust..

Pro tip: Indexation applies only to property purchased before July 23, 2024. If you bought after that date, long-term capital gains are taxed at a flat 12.5% with no indexation — recalculating won't help you in that case.