Derivatives

What is Call Option?

Definition

A call option gives the holder the right, but not the obligation, to buy a specified number of shares at a predetermined price (strike price) before a specific expiration date. Investors buy calls when they expect the stock price to rise, as calls increase in value as the underlying stock appreciates.

Detailed Explanation

A call option contract represents 100 shares of the underlying stock. If you buy a call option with a $100 strike price for $5 per share ($500 total), you have the right to buy 100 shares at $100 each until the expiration date. If the stock rises to $120, your option is worth at least $20 per share ($2,000), yielding a $1,500 profit on your $500 investment — a 300% return versus 20% from buying the stock outright.

Call options provide leverage: you control 100 shares for a fraction of the stock's price. However, this leverage works both ways. If the stock stays below $100 at expiration, your call expires worthless and you lose the entire $500 premium. Unlike stock ownership, options have a fixed expiration date — time works against the option buyer.

Calls are in-the-money (ITM) when the stock price exceeds the strike, at-the-money (ATM) when they are equal, and out-of-the-money (OTM) when the stock is below the strike. ITM calls have intrinsic value plus time value, while OTM calls consist entirely of time value and are cheaper but riskier.

Beyond speculation, calls are used for hedging (protecting short stock positions), income generation (covered calls), and capital-efficient exposure (LEAPS as stock substitutes). Institutional investors use calls extensively in complex strategies like spreads, straddles, and collars.

Formula

Call Profit at Expiration = Max(0, Stock Price - Strike Price) - Premium Paid

Example

Buy 1 AAPL $180 call for $5. If AAPL is at $195 at expiration, the call is worth $15. Profit: $15 - $5 = $10 per share ($1,000 per contract). If AAPL is at $175, the call expires worthless. Loss: $500.

Frequently Asked Questions

When should I buy a call option instead of stock?

Calls make sense when you have a strong directional conviction with a defined time horizon, want leverage on limited capital, or want to limit your downside to the premium paid. They are less suitable for long-term investing due to time decay and expiration. LEAPS (long-dated options) can serve as stock substitutes.

What happens if I don't sell my call before expiration?

If your call is in-the-money at expiration, it will be automatically exercised — you will buy 100 shares at the strike price (requiring the capital). If you don't have the capital or don't want the shares, sell the option before expiration. Out-of-the-money calls expire worthless automatically.

Related Terms

Put Option

A put option gives the holder the right, but not the obligation, to sell a specified number of shares at a predetermined strike price before expiration. Investors buy puts when they expect a stock price to decline or want to protect an existing stock position from downside risk.

Strike Price

The strike price (or exercise price) is the predetermined price at which an option holder can buy (for calls) or sell (for puts) the underlying asset. It is the most important factor in determining an option's value and risk/reward profile.

Implied Volatility (IV)

Implied volatility is the market's forecast of the likely magnitude of a stock's price movement, derived from option prices. High IV means options are expensive because the market expects large price swings, while low IV means options are cheap because calm conditions are expected.

Options Premium

The options premium is the price paid by the buyer to the seller for an option contract. It consists of intrinsic value (how much the option is in-the-money) and extrinsic value (time value plus volatility value). The premium represents the maximum loss for option buyers and maximum gain for option sellers.

See It in Action

Apple

Microsoft

Johnson & Johnson

Berkshire Hathaway

Disclaimer: The information on this page is provided for educational and informational purposes only and does not constitute investment advice. AI-generated analysis may contain errors or inaccuracies. Always conduct your own research and consult a qualified financial advisor before making investment decisions.