Why March Is the Most Important Month for Tax Harvesting
The Indian financial year ends on March 31. All capital gains and losses must be realized (meaning the sale must be settled) before this date to count for the current financial year. Any sale executed after March 31 falls into the next financial year.
This makes late February and March the critical window for tax loss harvesting. Most investors spend January reviewing their portfolio, February calculating the potential tax impact, and early March executing the harvesting transactions. Waiting until the last week of March is risky because of settlement timelines and market volatility.
With T+1 settlement now standard for equity trades in India, a trade executed on March 31 settles on April 1. This means the sale would technically fall into the next financial year for settlement purposes, although the trade date is what matters for tax purposes. Nevertheless, executing your harvesting plan by mid-March gives you a buffer for any complications.
This checklist walks you through every step you need to take before March 31 to optimize your capital gains tax through loss harvesting.
Step 1: Review Your Realized Gains for the Year
Start by calculating your total realized capital gains for the financial year. Your broker should provide a tax P&L statement that lists every completed trade. Look at the consolidated figures for:
- Total STCG from equity: Sum of all short-term profits from stocks and equity mutual funds sold within 12 months of purchase.
- Total LTCG from equity: Sum of all long-term profits from stocks and equity mutual funds sold after 12 months.
- Already-realized losses: Some losses may have been booked earlier in the year through regular trading activity. These are already factored into your tax P&L.
If your broker's statement shows net figures (gains minus losses), make sure you understand the breakdown. You need the gross gains and gross losses separately to plan your harvesting.
For Zerodha users, the Console tax P&L report provides a detailed breakdown. For other brokers, check their annual tax statement or contract notes. TaxHarvestLab can also import your holdings and compute these figures automatically.
Document these numbers. They are the starting point for calculating how much additional loss harvesting is worthwhile.
Step 2: Identify Unrealized Losses in Your Portfolio
Next, go through your current holdings and identify every position that is currently trading below your purchase price. These are your unrealized losses, which become realized losses only when you sell.
For each position, note:
- Stock name and quantity held
- Purchase date and purchase price (per lot if you have multiple lots)
- Current market price
- Unrealized loss amount
- Whether the loss is short-term or long-term (based on 12-month holding period)
Pay attention to the holding period. A stock bought on March 20, 2025, will become long-term on March 20, 2026. If you are reviewing in March 2026, this stock is right at the boundary. Selling it on March 19 makes it STCL. Selling it on March 21 makes it LTCL. This distinction matters for set-off flexibility.
Also check for FIFO implications. If you bought the same stock in multiple lots, FIFO determines which lot is sold first. The earliest lot might be profitable even if a later lot is at a loss. Run the FIFO calculation before assuming a sale will generate a loss.
Create a spreadsheet or use a tool like TaxHarvestLab that lists all harvestable losses ranked by the tax impact they would create.
Step 3: Check FIFO Cost Basis for Each Holding
This step is critical and often overlooked. If you have accumulated shares of the same company across multiple purchases, FIFO determines your cost basis for any sale.
For example, if you bought Reliance in 3 tranches: - 50 shares at Rs 2,400 on June 1, 2024 - 30 shares at Rs 2,600 on November 15, 2024 - 40 shares at Rs 2,800 on July 20, 2025
And the current price is Rs 2,500. If you sell 50 shares, FIFO assigns the June 2024 lot. Your gain is Rs 2,500 - Rs 2,400 = Rs 100 per share. That is an LTCG of Rs 5,000, not a loss.
To book a loss, you would need to sell past the first lot and into the second or third lots. But the first lot's gain offsets the later lots' losses.
This is why a FIFO-aware calculation is essential. Without it, you may execute a harvest expecting a loss and end up booking a gain instead. Your broker's holdings statement should show lot-level details. Verify these before placing any sell order.
TaxHarvestLab performs FIFO calculations automatically using your actual lot data, so you can see the exact gain or loss per lot before executing.
Step 4: Calculate the Tax Impact of Each Potential Harvest
For each unrealized loss you are considering harvesting, calculate the tax saving using these formulas:
If the loss is STCL and you have STCG to offset: Tax saved = STCL amount x 20.8% (including cess)
If the loss is STCL and you only have LTCG to offset (after STCG is exhausted): Tax saved = STCL amount x 13% (12.5% + cess)
If the loss is LTCL and you have LTCG to offset: Tax saved = LTCL amount x 13% (12.5% + cess)
If the loss is LTCL and you only have STCG: Tax saved = Rs 0 (LTCL cannot offset STCG)
Subtract the estimated transaction costs: brokerage (typically Rs 20 per order for discount brokers), STT (0.1% on sell side for delivery), GST (18% on brokerage), stamp duty, and SEBI charges. For a Rs 1,00,000 sell transaction, total costs are approximately Rs 200 to Rs 400.
If you plan to rebuy the stock, double the transaction cost estimate.
The net tax saving equals the gross tax saving minus all transaction costs. Only execute harvests where the net saving is clearly positive.
Step 5: Execute Before March 31
Once you have identified the optimal harvesting transactions, execute them during market hours. Here are the practical execution tips:
- Place market orders for liquid stocks to ensure execution. Limit orders risk non-execution if the price moves away from your limit.
- For illiquid stocks, use limit orders at the current bid price. Check that adequate volume exists before placing the order.
- If you plan to rebuy, execute the sell order first, confirm the trade, then place the buy order. Some brokers allow you to place both orders simultaneously.
- Keep a minimum 3 trading day buffer before March 31. This protects against exchange holidays, trading halts, or broker system outages.
- Save trade confirmations and contract notes. You will need these for ITR filing.
For the current financial year (FY 2025-26), the last trading day is March 31, 2026, assuming it falls on a weekday and is not a market holiday. Check the NSE/BSE holiday calendar to confirm.
Do not forget: the tax benefit is only realized when you file your ITR and claim the set-off. The sale itself is step one. Correct ITR filing is step two.
Step 6: File Your ITR on Time to Preserve Carry-Forward
If your harvested losses exceed your gains, the unabsorbed loss is carried forward. This carry-forward is only valid if you file your income tax return on or before the due date.
For most individual taxpayers, the ITR due date is July 31 of the assessment year. For FY 2025-26, the due date is July 31, 2026 (unless extended by the government).
Missing this deadline is fatal for carry-forward. There are no exceptions and no appeals. The loss is permanently forfeited.
When filing, make sure to:
- Report all capital gains and losses in Schedule CG of your ITR
- Fill Schedule CFL (Carry Forward of Losses) correctly if you have unabsorbed losses
- Report each stock transaction individually or use the consolidated method allowed by the tax department
- Verify that the carried-forward amount matches your calculation
If you are using ITR-2 or ITR-3, Schedule CG has dedicated sections for STCG, LTCG, STCL, and LTCL. Ensure that the set-off is applied in the correct order: STCL against STCG first, then against LTCG, then LTCL against LTCG.
Consider using a tax professional or a reliable online filing platform to avoid errors. A misreported loss or incorrect set-off can trigger a tax notice and delay your refund.
Quick Reference: The Complete March Checklist
Here is the complete checklist in summary form:
- Review broker's tax P&L statement for realized STCG and LTCG
- List all current holdings with unrealized losses
- Classify each unrealized loss as STCL or LTCL based on holding period
- Run FIFO calculations for stocks with multiple buy lots
- Calculate gross tax saving for each potential harvest
- Subtract transaction costs to get net tax saving
- Rank harvesting opportunities by net saving, highest first
- Execute sell orders by mid-March
- Rebuy if desired (no wash sale rule in India)
- Save all trade confirmations and contract notes
- File ITR before July 31 with correct Schedule CG and Schedule CFL
- Set a reminder for ITR filing deadline
This systematic approach ensures you capture every available tax-saving opportunity without mistakes. The most common error is leaving money on the table by not reviewing your portfolio before March 31. Even a quick 30-minute review can uncover thousands of rupees in potential tax savings.
See how this applies to your portfolio
Upload your Zerodha or Groww reports and get personalized recommendations in under 2 minutes.
Analyze My Portfolio FreeFrequently Asked Questions
What is the last date to sell stocks for tax loss harvesting in India?
March 31 is the last date of the financial year. Your sell trade must be executed on or before March 31 for the loss to count in the current FY. Plan for at least 3 trading days of buffer before this deadline.
Do I need to file ITR to claim the loss set-off?
Yes. You must file your ITR to claim the set-off of losses against gains. If you have unabsorbed losses that need to be carried forward, filing before the due date (usually July 31) is mandatory to preserve the carry-forward.
Can I use TaxHarvestLab to automate this checklist?
Yes. TaxHarvestLab imports your holdings from Zerodha and other brokers, performs FIFO calculations, identifies optimal harvesting opportunities, and calculates exact tax savings. It automates steps 1 through 4 of this checklist.