What Is Margin in F&O?
Margin in F&O (Futures and Options) trading is the collateral or security deposit that a trader must maintain with their broker to hold a derivatives position. Unlike buying shares in the cash segment where you pay the full value, F&O positions require only a fraction of the contract's total value as margin. This allows traders to take leveraged positions: controlling a larger contract value with a smaller capital outlay. However, losses are still calculated on the full contract value, making margin trading inherently risky.
Types of Margin in Indian F&O
- SPAN margin (Standard Portfolio Analysis of Risk): The minimum initial margin calculated by NSE using a risk-based portfolio margining system. It accounts for the worst-case loss on a position over a one-day period.
- Exposure margin: An additional margin buffer above SPAN, collected to cover any residual risk not captured by SPAN. Typically 2-5% of notional contract value.
- MTM (Mark-to-Market) margin: Daily profit or loss on futures positions is settled daily. If losses reduce your margin below the maintenance level, you receive a margin call.
Typical Margin Requirements (Approximate)
| Contract | Approximate Margin per Lot | Contract Value |
|---|---|---|
| Nifty 50 futures | Rs 55,000-70,000 | ~Rs 5.5 lakh |
| Bank Nifty futures | Rs 60,000-75,000 | ~Rs 6.75 lakh |
| Option selling (naked) | Rs 50,000-80,000 per lot | Varies |
| Option buying | Only premium paid (no additional margin) | Rs 2,000-20,000 |
Margin Call
A margin call occurs when your account's available margin falls below the required level due to adverse market movements. Your broker will either automatically square off (close) your positions to prevent further losses, or ask you to immediately deposit additional funds. In India, SEBI mandates that brokers auto-square positions at a defined margin shortfall level to prevent systemic risk.
Peak Margin Requirements (SEBI 2021)
SEBI implemented peak margin regulations from September 2021 requiring brokers to collect full margin (100% of SPAN + exposure margin) upfront before allowing any F&O trade. This eliminated intraday leverage/exposure in F&O provided by some brokers, making F&O trading capital-intensive but reducing systemic risk.
Key Takeaway
Margin is the essential capital requirement for F&O trading, determining both the leverage available and the risk exposure. Maintain adequate margin buffer to avoid forced position closures. Margin shortfalls can force stop-outs at the worst possible prices. Use the Lemonn app to understand margin requirements and calculate the capital needed before entering any F&O position in India.
