It wasn't a big mistake. That's almost the worst part.
₹690 is not a number that keeps you up at night. It's a number you never even notice — because nobody tells you it happened. You just pay a slightly higher tax bill in July, assume that's what trading costs, and move on.
But here's what actually happened.
I ran my Zerodha tradebook through Fynr — 2,816 transactions, one financial year of active equity trading. It found something I already vaguely knew but had never seen costed out in rupees.
I sold FEDERALBNK on 4th April 2024. Two lots. A loss of ₹2,367 and ₹1,083 respectively. Combined loss: ₹3,450.
The financial year had ended on 31st March — four days earlier.
Those losses could have offset ₹3,450 of my realised gains for FY2024-25. At a 20% STCG rate, that's ₹690 in tax I didn't have to pay. Gone. Simply because I sold four days too late.
The rule is Section 70 of the Income Tax Act. Capital losses can only offset capital gains within the same financial year. A loss booked on April 4th falls into FY2025-26. It cannot reach back and offset last year's gains, no matter how close to the deadline it was.
India's financial year ends on March 31st. Whatever you didn't sell before that date is a different year's problem.
FEDERALBNK wasn't a position I was planning to hold. I was going to exit it anyway. I just didn't get around to it before April. No particular reason — I wasn't watching the calendar. Nobody told me to.
FEDERALBNK wasn't alone. The same scan found 14 other scrips where I booked losses in the first two weeks of April — BATAINDIA, HINDALCO, MCX, BAJAJ-AUTO, INDUSINDBK, OFSS, TORNTPHARM, SBICARD, ICICIGI, BAJAJFINSV, GRASIM, NYKAA, UPL, ICICIBANK.
Combined losses across all of them: ₹38,852. Tax that could have been saved by selling before March 31st: ₹7,771.
Not life-changing money. But money that was entirely mine to keep. I just didn't know the window was closing.
For any of these positions to have saved me tax, I needed to identify before March 31st that I was holding positions in loss, sell them before the exchange closed, book the loss in FY2024-25, and offset it against my ₹5.79 lakh in STCG gains from the same year.
None of this is complicated. I just didn't know which positions to look at, or that the window was closing, or what it would cost me.
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Scan my tradebook →CA verification required on all outputs. This is not tax advice.