What is a Call Option?

Call options are an agreement that give the option buyer the right, but not the obligation, to buy a stock, bond, commodity or other instrument at a specified price within a specific time period. The stock, bond, or commodity is called the underlying asset.

A call buyer profits when the underlying asset increases in price.

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Call Option Basics

Key Takeaways

  • A call is an option contract giving the owner the right, but not the obligation, to buy a specified amount of an underlying security, such as a stock or a bond, at a specified price within a specified time. The specified price is known as the strike price and the specified time during which a sale is made is known as call auction.
  • The opposite of the call option is the put option, which gives the owner the right, but not the obligation, to sell a specified amount of an underlying security at a specified price within a specified time.

The Basics of a Call Option

Call options give the holder the right to buy 100 shares of an underlying stock at a specific price, known as the strike price, up until a specified date, known as the expiration date.

For example, a single call option contract may give a holder the right to buy 100 shares of Apple stock at $100 up until the expiry date in three months. There are many expiration dates and strike prices for traders to choose from. As the value of Apple stock goes up, the price of the option contract goes up, and vice versa. The call option buyer may hold the contract until the expiration date, at which point they can take delivery of the 100 shares of stock or sell the options contract at any point before the expiration date at the market price of the contract at that time.

The market price of the call option is called the premium. It is the price paid for the rights that the call option provides. If at expiry the underlying asset is below the strike price, the call buyer loses the premium paid. This is the maximum loss.

If the underlying's price is above the strike price at expiry, the profit is the current stock price, minus the strike price and the premium. This is then multiplied by how many shares the option buyer controls. For example, if Apple is trading at $110 at expiry, the strike price is $100, and the options cost the buyer $2, the profit is $110 - ($100 +$2) = $8. If the buyer bought one contract that equates to $800 ($8 x 100 shares), or $1,600 if they bought two contracts ($8 x 200).

If at expiry Apple is below $100, then the option buyer loses $200 ($2 x 100 shares) for each contract they bought.

Call options are typically used for three primary purposes. These are tax management, income generation, and speculation.

Using Options for Tax Management

Investors sometimes use options as a means of changing the allocation of their portfolios without actually buying or selling the underlying security. For example, an investor may own 100 shares of XYZ stock and be sitting on a large unrealized capital gain. Not wanting to trigger a taxable event, shareholders may use options to reduce the exposure to the underlying security without actually selling it. The only cost to the shareholder for engaging in this strategy is the cost of the options contract itself.

Using Options for Income

Some investors use call options to generate income through a covered call strategy. This strategy involves owning an underlying stock while at the same time writing a call option, or giving someone else the right to buy your stock. The investor collects the option premium and hopes the option expires worthless (below strike price). This strategy generates additional income for the investor but can also limit profit potential if the underlying stock price rises sharply. This is because if the stock rises above the strike price, the option buyer will exercise their right to buy the stock at the lower strike price. This means the option writer doesn't profit on the stock above the strike price. The options writer's maximum profit on the option is the premium received.

Using Options for Speculation

Options contracts give buyers the opportunity to obtain significant exposure to a stock for a relatively small price. Used in isolation, they can provide significant gains if a stock rises, but can also lead to a 100% loss of the premium if the call option expires worthless because the underlying stock price fails to move above the strike price. The benefit of buying call options is that risk is always capped at the premium paid for the option.

Real World Example of a Call Option

Suppose that Microsoft shares are trading at $108 per share. You own 100 shares of the stock and want to generate an income above and beyond the stock's dividend. You also believe that shares are unlikely to rise above $115.00 per share over the next month.

You take a look at the call options for the following month and see that there's a 115.00 call trading at $0.37 per contract. So, you sell one call option and collect the $37 premium ($0.37 x 100 shares), representing a roughly four percent annualized income.

If the stock rises above $115.00, the option buyer will exercise the option and you will have to deliver the 100 shares of stock at $115.00 per share. You still generated a profit of $7.00 per share, but you will have missed out on any upside above $115.00. If the stock doesn't rise above $115.00, you keep the shares and the $37 in premium income.