Call Options
What a call option is and how it works
What Is a Call Option?
A call option is a derivative contract giving the holder the right, but not the obligation, to buy an underlying asset at a specific price (the strike) on or before a specific date (expiration). The seller of the call receives a premium for selling that right. One equity option contract typically represents 100 shares. For example, if you buy a call on Apple with a $150 strike expiring in one month, you are paying for the right to buy 100 Apple shares at $150 at any point during that month. If the stock rises to $160, your option becomes profitable. If the stock falls to $140, you simply do not exercise, and your loss is limited to the premium paid.
Profit and Loss on Calls
The maximum gain from buying a call option is theoretically unlimited. If the share price rises without limit, your call keeps gaining value. Your maximum loss, however, is limited to the premium you paid. If you buy a call for $2.50 per contract, you lose a maximum of $250 ($2.50 × 100 shares) if the option expires worthless. Conversely, the seller of a call has a maximum gain limited to the premium received but potentially unlimited losses if the stock rises dramatically. For a call purchase to be profitable, price must rise enough to cover the premium paid. If you buy a call at $2.50, the stock must rise more than $2.50 per share to be profitable at exercise.
In the Money vs Out of the Money
A call option is said to be "in the money" (ITM) when the current share price is above the strike. For example, if a call has a $150 strike and the stock trades at $155, it is ITM by $5. A call is "out of the money" (OTM) when the current price is below the strike. If the stock trades at $145, a $150-strike call is OTM by $5. A call is "at the money" (ATM) when the current price equals or is very close to the strike. How far ITM or OTM an option sits significantly affects its value. ITM options carry intrinsic value on top of time value. OTM options carry only time value and depend on price moving in order to become profitable.
When to Use Calls: Common Strategies
Traders buy call options when they believe a share price will rise. It is the simplest way to use calls and carries a clearly bullish bias. Traders also use calls in spreads, buying one call and selling another simultaneously to reduce the cost. A common structure is the bull call spread, where you buy an ATM call and sell an OTM call. Call sellers usually hold a neutral or mildly bearish view, looking to capture the premium while the stock stays below the strike. Calls are also used as a hedge: buying calls against a short position caps that position’s potential losses.
Factors That Affect Call Prices
The price of a call option is driven by five main factors: the share price, the strike price, time to expiration, implied volatility and interest rates. A rise in the share price increases the value of a call. More time to expiration also increases value, because there is more time for the stock to move. A rise in implied volatility increases call value, because larger price moves become more likely. The delta of a call option (typically between 0 and 1) represents how much the option’s value changes when the share price rises by one dollar. Interest rates have a small but positive effect on call prices. Understanding how these factors interact is fundamental to trading options successfully.