Plain-English definitions, reviewed by an independent investor

Strike Price

The strike price is the fixed price at which an option lets you buy or sell the underlying stock.

The strike price is the fixed price at which an option lets you buy or sell the underlying stock.

(The preset exercise price in an option contract)

A quick example

A call option with a $50 strike gives you the right to buy the stock at $50 until expiry, no matter how high the market goes. If the stock trades at $60, the call is in the money by $10; at $45, it is out of the money and worthless at expiry. The strike is set when the contract is created, along with the expiry date, and the premium you pay reflects how far the strike sits from the current price. Strike prices are the coordinates of every option trade.

How to apply it

Pick strikes by the scenario you expect: deep out-of-the-money calls are cheaper but need a big move to pay; at-the-money strikes balance cost and responsiveness. Never buy a strike whose thesis you cannot articulate.

What it means for you

It defines whether an option is in or out of the money.

Picture this

A stock trades at $50, and a trader buys a $55 call for $1, expecting a rally. The stock climbs to $54 — close, but below the strike — and the call expires worthless. A $52 call would have paid off on the same move, but cost more upfront. The scenario is the strike trade-off in miniature: every dollar further from the money is a cheaper bet that needs a bigger move to win. Choosing the strike is really choosing your confidence in the size of the expected move.

Common mix-ups

An option is only exercised when it pays to do so versus the market price.

Key takeaway

The strike price is the fixed level at which an option lets you trade the underlying, and it defines whether the option is in or out of the money. Every dollar the strike sits from the current price changes the premium and the size of the move needed to profit. Deep out-of-the-money strikes are cheap bets that need big moves; at-the-money strikes balance cost and responsiveness. Choosing a strike is really choosing your confidence in the size of the expected move.

Definitions reviewed by the Investing Glossary editorial team.

Questions Investors Ask

In the money?

A call is ITM when the stock is above strike; a put when below.

Strike vs spot?

Strike is the contract price; spot is today’s market price.

What is at the money?

When the strike roughly equals the current stock price, the option’s hinge point.

How far apart are strikes?

Set by the exchange in fixed increments, $1 or $2.50 apart for most stocks.

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