Calculate the margin requirements for various options trading strategies. Understand how much capital you need to trade options safely.
Reg-T Margin
Portfolio Margin
Buying shares of stock
Formula: 50% of stock value
A margin call will be triggered if your account equity falls below the maintenance margin requirement.
Margin Call Buffer: $0.00
This is the amount your position can lose before triggering a margin call.
Disclaimer: This calculator provides estimates only. Actual margin requirements may vary by broker and market conditions. Always check with your broker for exact requirements.
The amount of capital required to open a position. This is the minimum equity you must have in your account to enter a trade.
The minimum amount of equity you must maintain in your account to keep your position open. If your account equity falls below this level, you'll receive a margin call.
Reg-T margin is the standard margin requirement set by the Federal Reserve. Portfolio margin is risk-based and can reduce requirements for hedged positions but requires a larger account (typically $125,000+).
| Strategy | Initial Margin (Reg-T) | Risk Level | Notes |
|---|---|---|---|
| Long Stock | 50% of stock value | MEDIUM | Buying shares of stock |
| Short Stock | 50% of stock value + additional requirements for volatile stocks | HIGH | Selling shares of stock you don't own |
| Long Call | 100% of option premium | MEDIUM | Buying call options |
| Long Put | 100% of option premium | MEDIUM | Buying put options |
| Short Call (Naked) | 20% of underlying value - OTM amount + option premium | HIGH | Selling uncovered call options |
| Short Put (Naked) | 20% of underlying value - OTM amount + option premium | HIGH | Selling uncovered put options |
| Covered Call | 50% of stock value (call is covered by stock) | LOW | Long stock + short call at higher strike |
| Cash-Secured Put | 100% of maximum purchase obligation (strike price × 100) | MEDIUM | Short put with cash to cover assignment |
| Vertical Spread | Difference between strikes × 100 | MEDIUM | Buy and sell options of same type at different strikes |
| Iron Condor | Maximum of the two spreads' width × 100 | MEDIUM | Combination of bull put spread and bear call spread |
| Butterfly Spread | Difference between adjacent strikes × 100 | LOW | Three strikes with ratio of 1:2:1 |
| Calendar Spread | Margin requirement of the short option | MEDIUM | Same strike, different expirations |
Trading on margin involves borrowing money from your broker to purchase securities. This can amplify both gains and losses. Never trade with money you cannot afford to lose, and always understand the risks involved with margin trading.
While this calculator provides estimates based on standard Reg-T and portfolio margin rules, actual margin requirements can vary significantly between brokers for several reasons:
House requirements above regulatory minimums
Risk-based adjustments for volatile stocks
Special requirements for earnings events
Account tier and history considerations
Higher requirements for meme stocks or IPOs
Lower requirements for hedged positions
Different calculations for portfolio margin
Overnight vs. intraday requirement differences
Always check with your specific broker for their current margin requirements before placing trades. Brokers may change requirements without notice, especially during periods of high market volatility.