What are stock options & how do they work?

Stock options are a powerful financial instrument that provides investors with flexibility and potential profit opportunities beyond traditional stock trading. Understanding how stock options work requires a grasp of various factors such as strike price, expiration date, and option type. While they can offer significant rewards, they also involve inherent risks and complexities, making it crucial for investors to understand how they function before incorporating them into their investment strategies.

Read this guide to embrace the possibilities to enhance your investment journey. Unlock the potential in your portfolio and construct a strategy that aligns with your financial goals and personality as an investor.

What is a Stock Option?

A stock option is a financial instrument that gives the holder the right to buy or sell a specific quantity of a particular stock at an agreed-upon price (the strike price) by a predetermined date (the expiration date). It is a contract between the buyer and the seller, typically an investor and a broker or market maker .

Working of Stock Options

Unlike stocks or bonds, which are assets, options represent the rights to buy or sell the underlying stock at a predetermined price within a specified timeframe. These options provide investors with flexibility and leverage, allowing them to potentially profit from price movements without actually owning the underlying asset. 

They act as contractual agreements between buyers and sellers, granting the buyer the choice to purchase or sell the underlying security at a specific price, known as the strike price option , within a predetermined period. This added layer of flexibility enables investors to take advantage of market fluctuations and potentially amplify their returns.

Moreover, they offer a unique way to manage risk. Instead of fully committing to the purchase or sale of the underlying asset, investors can limit their exposure by leveraging options contracts. This means that they can control a larger position in the market with a smaller upfront investment, potentially magnifying their gains if the market moves in their favour.

Types of Stock Options

Understanding its variations is crucial for investors. The two main types of stock options are:

Call Options

A call option , a type of financial derivative, grants the holder the right, but not the obligation, to purchase shares of a particular stock at a predetermined price, known as the strike price, within a specified time frame. This option is commonly regarded as a bullish strategy, indicating the belief that the stock’s price will surpass the strike price and the premium paid for the option. 

By utilising call options, investors can potentially capitalise on anticipated price increases and benefit from the upward movement of the underlying stock.

Put Options

A put option provides the holder with the valuable right to sell shares at a predetermined price within a specified time. This financial instrument is commonly employed as a bearish strategy, as it anticipates the stock’s price to decline below the strike price minus the premium. 

By utilising put options, investors can profit from a downward movement in the underlying stock, adding a layer of flexibility and risk management to their investment portfolios. Beyond these are other technical types, such as employee stock options (ESOs) and Warrants.

Features of Stock Options


The stock’s expected volatility strongly influences options pricing. More volatile stocks tend to have higher option premiums because they offer the potential for greater price swings.

Time Decay

Time decay is a vital aspect of option pricing. The value of options contracts diminishes as they get closer to the expiration date. This is because there is a lower chance of a significant price movement with less time.

Intrinsic and Extrinsic Value

An option’s total value is composed of its intrinsic and extrinsic value. Intrinsic value is how much an option is worth if it is immediately exercised, calculated by the difference between the current stock price and the strike price. Extrinsic value, or time and volatility value, is the price of an option beyond its intrinsic value.

How to Invest in Stock Options?

Investing in stock options involves identifying the right option to buy or write, considering the strategy and the market conditions. The steps to invest include:

  • Select a Strategy

    Choose from basic strategies, such as buying calls or puts, to more complex strategies, like strangles and spreads, based on your investment objectives and risk tolerance.

  • Analyse Market Conditions

    Determine the market’s direction and the potential impact on the underlying stocks or assets. Technical and fundamental analysis can help guide your predictions.

  • Research Underlying Assets

    Know the fundamentals of the companies you are trading options for and the industry and sector trends that may impact their performance.

  • Evaluate the Premiums

    The amount you will pay or receive for an option, known as the premium, is a key consideration in your potential returns. Ensure that the premium aligns with your strategy and expected returns.

  • Monitor Your Position

    Keep an eye on your options before and after you have purchased them. Knowing when to cut losses or take profits is as crucial as the initial investment decision.

How to Calculate the Value of Your Stock Options?

To calculate the value of your stock options, you’ll need to understand two main types of stock options: Incentive (ISOs) and Non-Qualified (NSOs). The calculation method is similar for both, but they are taxed differently.

Basic Calculation

The basic idea behind its value is to calculate the difference between the stock’s market price when you plan to exercise your options and the strike price at which you’re allowed to buy the stock.


Value of Stock Options=(Current Market Price−Strike Price)×Number of OptionsValue of Stock Options=(Current Market Price−Strike Price)×Number of Options

Considerations for Real-World Calculation

  1. Vesting Period

    You can only exercise your options after they have vested. If your company has a four-year vesting schedule, you may not exercise all your options immediately.

  2. Expiration Date

    If you don’t exercise your options before expiration, they become worthless.

  3. Taxes

    The difference between the market price and the strike price at the time of exercise is subject to taxation. ISOs and NSOs are taxed differently, potentially qualifying for more favourable tax treatment if conditions are met.

  4. Market Conditions

    The current market price can fluctuate, affecting the value of your options. The calculation above assumes you can predict or know the current market price, which is not always true.

  5. Liquidity and Sale

    Even if your options are “in the money” (the current market price is higher than the strike price), you need to be able to sell the shares to realise the gain. Market conditions, lock-up periods following an IPO, and company rules on share sales can influence this.

Various Stock Option Parameters

Several parameters and terms are essential. They are:

Strike Price

This is the price at which the option holder can buy (for call options) or sell (for put options) the underlying asset.

Expiration Date

Options expire on the expiry date specified in the contract. You must exercise your options before this date, or they will become worthless.

In-the-Money, At-the-Money, Out-of-the-Money

These refer to the current position of an option relative to the underlying stock. An in-the-money option has intrinsic value, an at-the-money option has a strike price equal to the stock’s current trading price, and an out-of-the-money option has no intrinsic value.

Open Interest

This is the number of open option contracts for a particular stock. High open interest suggests a large number of participants and potentially more liquidity.


As with any investment, thorough research, risk management, and strategic planning are key to maximising stock options. Whether you are employing options for their hedging capabilities, leveraging power, or as an addition to your portfolio, a deep dive into this realm of finance can present exciting opportunities for both seasoned and new investors alike.

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