Pledged margin for algo trading: use the shares you hold
How pledging shares and fund units gives collateral margin for F&O strategies, the haircuts and 50% cash rule, costs and risks, with worked numbers.
Also in: हिंदी
Most retail algo portfolios in India do not run on fresh cash. They run on pledged margin: shares and mutual fund units you already own, pledged to your broker as collateral, against which the exchange grants margin for F&O positions. The holdings stay yours; the strategies trade on the margin they unlock.
How pledging works
Select holdings, authorise with a CDSL OTP. The shares stay in your demat, marked "pledged".
Typically 10–25% for large-cap stocks and liquid funds, more for volatile names. ₹10 lakh of Nifty 50 shares at a 15% haircut gives ₹8.5 lakh of collateral margin.
At least half the margin used for positions must be cash or cash-equivalent (liquid fund units, G-secs, cash balance). Pledged stock covers the rest.
Index options and futures positions are sized against the available margin, with room kept for adverse moves.
A worked example
₹1 crore portfolio: ₹60 lakh in large-cap stocks, ₹40 lakh in a liquid fund. After haircuts, about ₹51 lakh of stock collateral and ₹38 lakh of cash-equivalent collateral. Under the cash rule, usable margin is roughly ₹76 lakh (2× the cash component, capped by the total). A rule-based F&O book would typically use half of that and keep the rest as buffer.
Costs
Pledge and unpledge charges (a few rupees to ~₹30 per scrip per request, broker-dependent), and interest on any shortfall in the cash component if you let the broker fund it — which a well-run portfolio does not.
Risks
- Collateral value falls. A market drawdown shrinks both your pledged value and, often, your positions at the same time. Margin calls follow.
- Concentration. Pledging a single stock and trading on it doubles your exposure to that name.
- Square-off. Unmet margin calls end in the broker closing positions at its timing, not yours.
This is why Firefly's portfolio drawdown limit sits well inside the margin math: exposure is cut across the board at a level you chose, long before the broker has to act.
Firefly Terra on pledged margin →
Questions people ask
Do I lose ownership when I pledge?
No. The shares stay in your demat account, marked as pledged. You keep dividends and voting rights. The broker can invoke the pledge only if you fail to meet a margin obligation.
What is the 50% cash rule?
Exchanges require at least half of the margin for F&O positions to be in cash or cash-equivalent collateral (liquid funds, G-secs, cash). Pledged shares can cover the other half.
What happens in a drawdown?
If the value of pledged collateral falls or positions lose money, the broker calls for more margin; if it is not met, positions are squared off. A platform's drawdown limit exists to cut exposure long before that point.
Fintrens Technologies Pvt Ltd is not a SEBI-registered investment adviser or research analyst. This guide is general information, not advice; trading involves risk of loss.
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