Why F&O Margins, Symbols, and Lot Sizes Matter for Beginners
What is Futures and Options (F&O) Trading?
F&O trading involves derivative contracts where you bet on or hedge against price movements of assets like Nifty or Bank Nifty:
- Futures: Contracts to buy/sell an asset at a fixed price on a future date (e.g., Nifty futures at ₹25,000).
- Options: Contracts giving the right (not obligation) to buy (Call) or sell (Put) an asset.
- Leverage: Trade large positions with small capital (e.g., ₹1.5 lakh controls ₹18.75 lakh Nifty contract).
- Risk: High leverage means high risk, making margin and lot size knowledge essential.
Understanding F&O margins, symbols, and lot sizes helps beginners navigate NSE’s F&O market, especially with SEBI’s 2024 lot size updates (Nifty: 75, BankNifty: 35).
10 Essential F&O Concepts for Beginners
What is SPAN Margin?
- How It Works:
- SPAN software simulates worst-case price and volatility changes (99% Value at Risk, one-day horizon).
- Varies by contract: Futures need higher margins; option buyers need none (premium only).
- Updated daily based on India VIX (e.g., VIX 15 = lower margin, VIX 20 = higher).
- Detailed Example:
- You decide to trade 1 lot of Nifty futures (lot size = 75, Nifty at ₹25,000).
- Contract value: 75 × ₹25,000 = ₹18.75 lakh.
- SPAN margin: ~12% (NSE, 2025) = ₹2.25 lakh.
- Scenario: On Zerodha, you check the Margin Calculator. For Nifty futures, SPAN margin is ₹2,25,000, covering a potential 12% drop (₹3,000 points, e.g., Budget Day 2025 crash). If VIX spikes to 20 (e.g., post-RBI policy), SPAN margin rises to ₹2.5 lakh, requiring extra funds.
- Why It Matters: Ensures your account can handle market volatility without liquidation.
Contract | Lot Size | Nifty Value | Contract Value | SPAN Margin (~12%) |
---|---|---|---|---|
Nifty Futures | 75 | ₹25,000 | ₹18.75 lakh | ₹2.25 lakh |
What is Exposure Margin?
Exposure margin is an additional margin brokers charge to cover unexpected price gaps beyond SPAN margin.
- How It Works:
- Typically, 4-5% of contract value (e.g., Zerodha: 5%, Upstox: 4.5%).
- Protects against sudden moves (e.g., global events impacting BankNifty).
- Detailed Example:
- Nifty futures (1 lot, ₹18.75 lakh).
- Exposure margin: 5% = ₹93,750.
- Scenario: You trade Nifty futures on Groww. On a stable day (VIX = 15), exposure margin is ₹84,375 (4.5%). During a volatile event (e.g., US election results, November 2024), Groww raises it to ₹1.12 lakh (6%) to cover a potential 5% gap (₹1,250 points). You compare with Zerodha (₹93,750, 5%), choosing Groww to save ₹9,375.
- Why It Matters: Acts as a safety net, preventing broker losses during market shocks.
- Tip: Check exposure margins across brokers for cost efficiency.
Contract | Contract Value | Exposure Margin (5%) |
---|---|---|
Nifty Futures | ₹18.75 lakh | ₹93,750 |
What is Total Margin?
- Formula: Total Margin = SPAN Margin + Exposure Margin
- Detailed Example:
- Nifty futures (1 lot, ₹18.75 lakh).
- SPAN margin: ₹2.25 lakh (12%).
- Exposure margin: ₹93,750 (5%).
- Total margin: ₹2.25 lakh + ₹93,750 = ₹3.18 lakh.
- Scenario: You have ₹3 lakh in your Upstox account. You try to buy 1 Nifty futures lot (NRML), but Upstox rejects it due to a ₹18,750 shortfall. You either deposit ₹20,000 more or switch to intraday (MIS, ₹1.5 lakh). If you sell a Nifty Call (premium = ₹7,500), no margin is needed, making it beginner friendly.
- Why It Matters: Determines your capital needs; shortfall leads to margin calls or rejected trades.
Contract | SPAN Margin | Exposure Margin | Total Margin |
---|---|---|---|
Nifty Futures | ₹2.25 lakh | ₹93,750 | ₹3.18 lakh |
What is Intraday Margin?
Intraday margin is a lower margin for F&O trades closed within the same day, offering higher leverage.
- How It Works:
- Leverage: 10-20x vs. 5x for overnight (NRML) trades.
- SEBI (2021): Square off by 3:20 PM, else NRML margin applies.
- Detailed Example:
- Bank Nifty futures (1 lot, lot size = 35, Bank Nifty at ₹51,000, contract value = ₹17.85 lakh).
- Intraday margin: ~8% = ₹1.43 lakh (vs. ₹3.03 lakh NRML).
- Scenario: On Zerodha, you buy 1 BankNifty futures lot (MIS) at 10 AM with ₹1.5 lakh margin. BankNifty rises 3% (₹1,530 points), earning ₹53,550 (35 × ₹1,530). You square off at 2 PM, saving ₹1.6 lakh vs. NRML margin. If you miss the 3:20 PM cutoff, Zerodha charges ₹3.03 lakh or liquidates at a penalty.
- Why It Matters: Affordable but risky due to time pressure.
- Risk: Auto square-off or penalties for missing deadlines.
Contract | Intraday Margin (~8%) | NRML Margin (~17%) |
---|---|---|
BankNifty Futures | ₹1.43 lakh | ₹3.03 lakh |
What is NSE Symbol?
- How It Works:
- Format: [Underlying][Expiry][Type][Strike].
- Example: NIFTY25AUG25000CE (Nifty, August 2025, 25,000 Call).
- Detailed Example:
- You plan to buy a Nifty Call option (lot size = 75, strike = 25,500, expiry August 2025).
- NSE symbol: NIFTY25AUG25500CE, premium = ₹150.
- Cost: 75 × ₹150 = ₹11,250 (no margin for buying options).
- Scenario: On Groww, you search NIFTY25AUG25500CE, see open interest (OI) = 1 lakh, ensuring liquidity. You buy 1 lot, expecting a 2% Nifty rise (₹500 points, ₹37,500 profit). Mistaking it for NIFTY25AUG25500PE (Put) could lead to a loss if Nifty rises.
- Why It Matters: Wrong symbol = wrong trade, risking lakhs.
- Tool: Verify symbols on NSE Website.
Contract | NSE Symbol | Description |
---|---|---|
Nifty Call | NIFTY25AUG25000CE | August 2025, 25,000 Call |
BankNifty Put | BANKNIFTY25AUG51000PE | August 2025, 51,000 Put |
What is ISIN?
ISIN (International Securities Identification Number) is a 12-character code identifying F&O contracts globally.
- How It Works:
- Format: IN (India) + 10 alphanumeric characters (e.g., INF204KB15I7).
- Used for settlement and compliance in demat accounts.
- Detailed Example:
- You trade 1 Bank Nifty futures lot (ISIN: INF204KB16J8, lot size = 35, ₹17.85 lakh).
- Margin: ₹3.03 lakh (NRML).
- Scenario: On Upstox, post-trade, the ISIN appears in your CDSL statement for tracking. At expiry, NSE uses ISIN to settle cash (index contracts don’t deliver physically). Beginners rarely interact with ISIN but may see it in broker reports.
- Why It Matters: Ensures global tracking, useful for institutional compliance.
Contract | ISIN | Description |
---|---|---|
BankNifty Futures | INF204KB16J8 | BankNifty futures, August 2025 |
What is Haircut Percentage?
Haircut percentage is the discount applied to collateral used for F&O margin funding.
- How It Works:
- SEBI/NSE sets haircuts (e.g., 20% for Nifty 50 stocks, 50% for small-caps).
- Usable margin = Collateral value × (1 – Haircut %).
- Detailed Example:
- You pledge ₹3 lakh TCS shares (haircut = 20%) on Zerodha for Nifty futures (margin = ₹3.18 lakh).
- Usable margin: ₹3 lakh × (1 – 0.2) = ₹2.4 lakh.
- Cash needed: ₹3.18 lakh – ₹2.4 lakh = ₹78,000.
- Scenario: If you pledge ₹3 lakh small-cap shares (50% haircut), usable margin = ₹1.5 lakh, requiring ₹1.68 lakh cash. Choosing TCS saves ₹90,000, making it cost-effective.
- Why It Matters: Higher haircuts reduce usable margin, increasing cash needs.
Collateral | Value | Haircut % | Usable Margin |
---|---|---|---|
TCS Shares | ₹3 lakh | 20% | ₹2.4 lakh |
Small-Cap Stock | ₹3 lakh | 50% | ₹1.5 lakh |
What is Collateral in F&O Trading?
- How It Works:
- Types: Cash, fixed deposits, NSE-approved stocks (e.g., Reliance, HDFC Bank), T-bills.
- SEBI rule: Minimum 50% cash or equivalents.
- Haircuts applied to non-cash collateral (e.g., 20-50%).
- Detailed Example:
- You trade 1 Nifty futures lot (margin = ₹3.18 lakh).
- Collateral: ₹1.5 lakh cash + ₹2 lakh Reliance shares (20% haircut = ₹1.6 lakh usable).
- Total: ₹1.5 lakh + ₹1.6 lakh = ₹3.1 lakh (₹8,000 shortfall).
- Scenario: On Zerodha, you pledge Reliance shares via CDSL. If you use small-cap stocks (50% haircut = ₹1 lakh usable), you’d need ₹2.18 lakh cash, increasing costs. You add ₹10,000 cash to cover the shortfall and trade.
- Why It Matters: Reduces cash outflow but requires smart collateral choices.
Collateral | Value | Haircut % | Usable Margin | Cash Needed |
---|---|---|---|---|
Reliance Shares + Cash | ₹2 lakh + ₹1.5 lakh | 20% | ₹1.6 lakh | ₹1.58 lakh |
Small-Cap Shares + Cash | ₹3 lakh + ₹1.5 lakh | 50% | ₹1.5 lakh | ₹1.68 lakh |
What is Lot Size in F&O Trading?
Lot size is the fixed number of units in an F&O contract, revised by SEBI (November 2024).
- How It Works:
- Nifty futures/options: Lot size = 75 (was 25).
- Bank Nifty: Lot size = 35 (was 15).
- Stocks: E.g., Reliance = 500 (was 250), Tata Steel = 1100 (was 550).
- Contract value = Lot size × Underlying price.
- Detailed Example:
- Nifty Call option (lot size = 75, strike = 25,500, premium = ₹150).
- Cost: 75 × ₹150 = ₹11,250 (pre-2024: ₹2,500 for lot size 25).
- Scenario: On Dhan, you buy 1 Nifty Call (NIFTY25AUG25500CE). Nifty rises 2% (₹500 points), earning ₹37,500 (75 × ₹500). Higher lot size means higher capital but same leverage. For Reliance futures (500 × ₹2,500 = ₹12.5 lakh), margin = ₹2.1 lakh.
- SEBI Update (Nov 2024):
- Nifty: 75, Bank Nifty: 35, Sensex: 20, Bankex: 30.
- Stocks: HDFC Bank (250 to 500), Tata Steel (550 to 1100).
- Why: Minimum contract value raised to ₹15 lakh to reduce speculation.
- Why It Matters: Higher lot sizes increase capital needs, impacting beginners.
Contract | Old Lot Size | New Lot Size | Underlying Value | Contract Value | Margin (NRML) |
---|---|---|---|---|---|
Nifty Futures | 25 | 75 | ₹25,000 | ₹18.75 lakh | ₹3.18 lakh |
BankNifty Futures | 15 | 35 | ₹51,000 | ₹17.85 lakh | ₹3.03 lakh |
Reliance Futures | 250 | 500 | ₹2,500 | ₹12.5 lakh | ₹2.1 lakh |
Practical Tips for F&O Beginners
To trade effectively, follow these steps:
- Calculate Margins:
- Use Zerodha/Sensibull calculators for SPAN, exposure, and total margins.
- Example: Bank Nifty futures (₹17.85 lakh) = ₹3.03 lakh NRML or ₹1.43 lakh MIS.
- Verify NSE Symbols:
- Double-check symbols (e.g., NIFTY25AUG25000CE) before trading.
- Use NSE website or broker apps.
- Optimize Collateral:
- Pledge low-haircut stocks (e.g., Reliance, 20%) to maximize usable margin.
- Maintain 50% cash as per SEBI rules.
- Account for Lot Size:
- Plan capital for new lot sizes (e.g., Nifty 75 = ₹11,250 for options).
- Start with options (lower cost) vs. futures.
- Use Tools:
- Sensibull: Margin and payoff analysis.
- TradingView: Track Nifty/BankNifty trends.
- Excel: Build margin trackers
Contract | Contract Value | Margin (NRML) | Margin (MIS) | Collateral (20% Haircut) |
---|---|---|---|---|
Nifty Futures | ₹18.75 lakh | ₹3.18 lakh | ₹1.5 lakh | ₹2 lakh shares + ₹1.58 lakh cash |
Common F&O Mistakes to Avoid
- Underfunding Margins: Not having enough for total margin (e.g., ₹3 lakh vs. ₹3.18 lakh).
- Wrong NSE Symbols: Trading NIFTY25AUG25000PE instead of CE.
- Ignoring Lot Size Changes: Assuming old Nifty lot (25) vs. new (75).
- Poor Collateral Choices: Pledging high-haircut stocks (50%) increases cash needs.
- Over-Leveraging: Using 20x intraday leverage risks wipeouts.