Pricing of options

Understanding how options are priced can help you to make smart investment decisions

Terms used in pricing options

When considering options it is important to understand the terms used.

An option's premium is the only element of the option not specified by ASX. It is influenced by a number of factors, including the price and volatility of the underlying stock, the option's exercise price and the time until expiry. An option's premium can be broken into two parts, intrinsic value, and time value:

Premium = intrinsic value + time value

Intrinsic value is the difference between the option's exercise price and the current share price. It cannot be less than zero. An option invariably trades at no less than intrinsic value. Call options have intrinsic value if the share price is above the exercise price. Put options have intrinsic value if the share price is below the exercise price.

An option has intrinsic value if exercising the option would result in you buying or selling the shares at a price better than the current share price.

Before expiry, an option often trades for more than its intrinsic value. The part of the premium over and above its intrinsic value is its time value. Shares do not have a time value component, as they have no expiry date. Options, on the other hand, are a wasting asset, and an important part of their value is the time remaining in the option's life.

There is a 'shorthand' commonly used to refer to options, according to the option's strike price and the current share price. It's worth being familiar with these terms:

In the money (ITM): Share price is above the strike price of a call, or below the strike price of a put.

Out of the money (OTM): Share price is below the strike price of a call, or above the strike price of a put.

At the money (ATM): Share price is the same as, or close to, the strike price.

What affects an option’s time value?

Time to expiry

The longer the time to expiry, the greater an option's time value (both calls and puts), all else equal.

Learn more

Volatility

The more volatile the stock, the higher the option's premium, all else equal.

Learn more

Dividends

If the stock goes ex-dividend during the option's life, option pricing is usually affected.

Learn more

Interest rates

Increases in interest rates can lead to higher call premiums and lower put premiums, all else being equal.

Learn more

Resources

Pricing tool

Traders must make assumptions about a security price behaviour over the option's life. The margin estimator can help you to estimate prices.

Margin estimator

ASX Online Courses

Both courses have 10 modules with each module taking 20-25 minutes to complete

Introduction to Options

Options are flexible tools that appeal to active investors. Take this course to learn how to magnify profits or protect your portfolio by buying or selling options.

Advancing in Options

This course will extend your knowledge of options trading beyond the introductory course. Learn about multi-legged strategies, margins and option pricing in detail.

Options Trading Game

Challenge your knowledge of options and sharpen your trading skills.

Advanced charting tool

Analysis tools

Apply your technical analysis skills using the advanced charting tool. You can create your own charts with 8 different chart types, technical indicator overlays, update chart intervals, add dividend events, or run company code price comparisons.

Cost of trading in options

When you trade an option, the value of the trade is generally lower than if you were to trade the same number of the underlying shares. Because of this, options are generally a cost efficient way to trade your view of a stock. There are three types of costs to consider.

Brokerage varies and can be:

a flat fee, charged on a per transaction basis
on a percentage basis i.e. a percentage of the gross value of the order, or
a combination of these two, such as a flat fee for orders up to a certain dollar value, and then a percentage charge thereafter.