Call vs Put Options: A Clear Guide for UK Investors

What Are Options? A Brief Overview

An option is a financial contract that gives the holder the right, but not the obligation, to buy or sell an underlying asset at a predetermined price within a specified timeframe. The underlying asset might be shares, indices, commodities or currencies.

Options are derivatives, meaning their value derives from something else (the underlying asset). Two parties exist in every options contract: the buyer (holder) and the seller (writer). The buyer pays a premium upfront for the rights that the contract provides. The seller collects that premium but takes on an obligation if the buyer chooses to exercise the option.

Think of an option as like a reservation fee at a restaurant. You pay a small amount to secure your table, but you are not forced to dine there. If plans change, you forfeit the fee but have no further obligation. The restaurant keeps your deposit regardless.

Two fundamental types of options exist: calls and puts. Each serves a different purpose and reflects a different market view.

What Is a Call Option?

A call option gives the holder the right to buy an underlying asset at a specified price, known as the strike price, before or on a specific expiration date. Call buyers typically anticipate that the underlying asset’s price will rise.

How Call Options Work

When you purchase a call option, you pay a premium to the seller. In return, you gain the right to buy the underlying asset at the strike price. If the market price rises above your strike price, your option gains value because you hold the right to buy at a lower price than the current market.

The seller of the call receives the premium and takes on the obligation to sell the asset at the strike price if you exercise. Sellers often hold the underlying asset already, which is called writing a covered call. Selling calls without holding the asset, known as a naked call, carries substantial risk.

Key terms for call options:

• Strike price: The fixed price at which you can buy the asset

• Premium: The cost you pay for the option

• Expiration date: When the contract expires

• In the money: When the asset price exceeds the strike price

• Out of the money: When the asset price is below the strike price

Example of a Call Option

Suppose shares in Company X trade at £50. You believe the price will rise over the next three months. You purchase a call option with a £55 strike price, paying a £3 premium per share.

Scenario A: The share price rises to £65. Your option is in the money. You can exercise your right to buy at £55, gaining £10 per share minus the £3 premium, resulting in a £7 profit per share. This simplified example ignores commissions/fees, spreads and tax, and assumes you can close or exercise at these prices.

Scenario B: The share price stays at £50 or falls. Your option expires worthless. You lose the £3 premium, but nothing more.

Your maximum loss as a buyer is typically limited to the premium paid (plus any costs/fees). However, if you sell call options, your potential losses can be substantial if the price rises significantly.

What Is a Put Option?

A put option gives the holder the right to sell an underlying asset at the strike price before or on the expiration date. Put buyers typically expect the underlying asset’s price to fall.

How Put Options Work

When you buy a put option, you pay a premium for the right to sell at the strike price. If the market price falls below your strike price, your put gains value. You hold the right to sell at a higher price than the current market offers.

The seller of the put collects the premium and accepts the obligation to buy the asset at the strike price if you exercise. Put selling can result in significant losses if the underlying asset’s price falls sharply.

The key terms for put options mirror those for calls:

• Strike price: The fixed price at which you can sell

• Premium: The cost of the option

• Expiration date: When the contract expires

• In the money: When the asset price is below the strike price

• Out of the money: When the asset price exceeds the strike price

Example of a Put Option

Company Y shares trade at £40. You believe the price will decline. You purchase a put option with a £35 strike price, paying a £2 premium per share.

Scenario A: The share price falls to £25. Your option is in the money. You can sell at £35 when the market price is £25, gaining £10 per share minus the £2 premium, resulting in an £8 profit per share. This simplified example ignores commissions/fees, spreads and tax, and assumes you can close or exercise at these prices.

Scenario B: The share price rises to £45. Your option expires worthless. You lose the £2 premium, but nothing more.

As with calls, your maximum loss as a put buyer is typically limited to the premium paid (plus any costs/fees). Selling puts, however, exposes you to losses if prices fall significantly.

Call vs Put Options: Key Differences at a Glance

Both calls and puts share structural similarities: both involve premiums, strike prices and expiration dates. The fundamental difference lies in the direction of the bet and the rights conveyed.

American Options vs European Options

Options come in two main styles that determine when you can exercise them. Understanding American options vs European options matters because it affects flexibility and your potential strategy.

American options allow the holder to exercise at any point before or on the expiration date. This flexibility can be valuable, particularly when dividends are involved or when early exercise provides strategic benefits.

European options allow exercise only on the expiration date itself, not before.

Despite the names, both styles trade globally. Many index options are European-style, while individual stock options are often American-style.

American vs European Options:

Neither style is inherently superior. European options may trade at lower premiums because they offer less flexibility. Your choice depends on the specific market, underlying asset and strategy.

Understanding the Risks of Options Trading

Options trading involves substantial risks that you must understand before participating. These risks go beyond losing your premium.

Options trading is not suitable for all investors. You can lose more than your initial investment, particularly when selling options or using leverage.

Key risks include:

• Time decay: Options lose value as expiration approaches, even if the underlying price moves favourably.

• Volatility risk: Changes in market volatility affect options prices.

• Liquidity risk: Some options have limited trading activity.

• Complexity risk: Misjudging strike prices, expiration dates or market conditions can lead to losses.

• Leverage risk: Options provide leveraged exposure, amplifying both gains and losses.

What Is a Margin Call?

A margin call is simply a demand from your broker to deposit additional funds or close positions when your account falls below required levels. This occurs in margin accounts where you borrow money to trade.

When trading options on margin, adverse price movements can trigger margin calls. If you cannot meet the call, your broker may liquidate positions without your consent, potentially at unfavourable prices.

Margin calls represent a real danger for options traders, particularly those selling options or using complex strategies. Proper position sizing and understanding your broker’s margin requirements helps manage this risk.

When Might Traders Use Calls or Puts?

Traders use calls and puts for various purposes beyond simple directional bets. Understanding these applications can help illustrate why options exist.

Speculation: Traders expecting price increases might buy calls. Those expecting declines might buy puts. Options provide leveraged exposure with limited downside for buyers. However, buyers can still lose 100% of the premium quickly and options can expire worthless.

Hedging: Investors holding shares might buy puts as insurance against price falls. This is sometimes called a protective put. The premium acts like an insurance cost.

Income generation: Investors might sell covered calls against shares they own, collecting premiums. This works best when expecting stable or slightly rising prices.

Common scenarios for calls and puts:

Each strategy carries distinct risks and potential rewards. No single approach suits all market conditions or investor circumstances.

Summary: Key Points to Remember

Call and put options represent two sides of the same concept. Calls grant the right to buy an asset, while puts grant the right to sell.

Key points include:

• Call options suit those expecting prices to rise.

• Put options suit those expecting prices to fall.

• Buyers risk only the premium; sellers face potentially larger losses.

• American options allow exercise before expiration, while European options allow exercise only at expiration.

• Time decay works against option buyers.

• Margin calls can force position closures when trading on margin.

Options trading is complex and carries significant risk. Before trading options, ensure you understand the mechanics fully, consider your risk tolerance carefully and never invest more than you can afford to lose.