Calendar vs. Diagonal vs. Ratio Spreads: Pick the Right Time-Structure Strategy

Time-structure option strategies and their correct use in the options market could mean the difference between unexpected losses and consistent profits for traders, specifically those who are interested in leveraging option expiry differences to manage volatility exposure and time decay. In today’s post, we are going to be taking a look at options trading strategies (calendar vs. diagonal vs. ratio spreads) for a deeper understanding of these time-structure option strategies.

It’s critical that you choose the right strategy based on market outlook and volatility, but there’s no need to fret because we will be addressing the key differences between these options, time spreads, and the ideal market conditions and environment to use each. As we compare calendar, diagonal, and ratio spreads, our hope is to help our readers out with the tools necessary for stronger and more strategic decision-making using volatility-based option strategies.

Strategy Basics: What Are Time-Structure Spreads?

Time-structure spreads are multi-leg option strategies that traders construct by using options with different expiration dates, but each one is designed to capture a different market outlook, though each one is designed to leverage time decay and volatility changes in some shape or form. Also known as “horizontal spreads,” time structure spreads are most notable for the fact that they all share the foundation in different expiration dates.

You’ll see below how this is the case, but also how each spread has its unique design and purpose for traders.

• Calendar Spreads: These neutral market outlook spreads involve buying and selling options of the same kind on the same underlying asset, but each option comes with a different expiration date. The strike prices are the same, and the aim is for traders to profit from the difference in time decay and IV between the two contracts.
• Diagonal Spreads: Traders use these spreads when they’re feeling mildly bearish or bullish on the markets. It’s where they buy and sell options on the same underlying asset, but different expiries and strikes are used. This lets traders profit from directional moves and from time decay in the options contracts they’re using.
• Ratio Spreads: This one is a bit different from calendar or diagonal spreads. Traders buy and sell an unequal number of contracts with the same underlying and expiration date. However, the ratio spread uses different strike prices. The profit and loss potentials are often uneven as they aren’t equal in both directions.

Calendar vs. Diagonal vs. Ratio Spreads at a Glance

Calendar Spreads Explained

The calendar spread, like all the other time-structure strategies discussed in this guide, uses different expiration dates on all the legs involved in the spread. Traders will typically want to use the calendar spread when they’re feeling neutral on market direction, that is, they aren’t sure if the stock price is going to go in a bearish or bullish direction. The end goal with the calendar spread is to profit from the IV and time decay differences between the two option contracts.

Structure

The more basic idea behind the calendar spreads structure is that traders are selling near-term options and buying longer-term options (same strike), but that’s not all. The following characteristics can also be found with calendar spreads:

• The same underlying asset (stocks, indices, etc.).
• The same strike price.
• Different expiration dates (one option expires sooner than the other).
• The long leg (the longer-dated option) is usually bought.
• The short leg (the nearer-dated option) is usually sold.
• The cost of the bought option is greater than the premium received from selling the options (net debit).

Ideal Market Conditions

The calendar spread is best used in a market where the underlying asset’s price is expected to remain relatively stable. If it’s going to move, it’s only within a narrow range around the strike price. This represents a neutral market outlook on the trader’s part because they aren’t envisioning major price swings that would take the stock in a bearish or bullish direction.

Low Implied Volatility

Traders will experience the most profitable outcome when implied volatility is low at the time they enter the trade. However, there’s an expectation that IV could increase moderately in the future. The value of the spread goes up due to this expectation coming true, as the long-term option will benefit from this increase in IV in the long term.

Difference in Time Decay

Another ideal scenario for the calendar spread is when there is a big difference between the impacts of time decay on the long and short options. The short leg losing a ton of value as it gets closer to its expiry benefits the trader because a large discrepancy between the short leg that loses a lot of value and the long leg that retains its value widens the profit potential of the spread.

Profit Drivers

What needs to happen to ensure that a calendar spread secures a profit for the trader who set it up? Let’s look over the two primary profit drivers for this strategy, which you’ll soon discover is a careful interplay between implied volatility and the time decay factor.

• Time Decay: Calendar spreads profit the most when there is considerable time decay on the short leg of the setup. As the short option decays more quickly than the long option, it provides a potential income stream as the premium devalues and the long-term option retains its value.
• Changes in IV (Rise): The longer option, which is owned by the trader, will go up in value when there is a rise in implied volatility. It gains value more so than the shorter option, and this can result in a higher profit potential overall for those using the calendar spread.

Risks and Considerations

Keep these risks in mind before using the time-structure strategy of the calendar spread.

• The Expiration Date: Choosing the wrong expiration date for the calendar spread can result in early assignment risk if the underlying asset price is near the strike price at the expiration date for the short leg option. A big problem can arise if the long leg doesn’t have enough value to offset the loss of early assignment.
• Volatility: Increasing IV can erode profitability, especially with the short leg option, and decreasing IV can negatively impact the value of the spread if the long leg option loses more value than the short leg.
• Unlimited Losses Possibility: If the underlying asset price goes considerably above the strike price of the short call option as the expiration date draws near, the short-term option that makes up the spread can be subject to unlimited losses, at least in theory.

Diagonal Spreads Explained

Diagonal spreads are designed around a directional market outlook, being either slightly bearish or bullish. Traders profit from directional moves with the stocks they’re trading, and diagonal spreads also profit from the time decay that works on each contract as it draws nearer to expiration.

Important Note: The key difference between the diagonal spread and a calendar spread, which we previously discussed, is that the diagonal spread offers a lot more flexibility with strike price selection, and it offers the chance for traders to profit from a market outlook that has a directional bias. Compared to the calendar spread, the diagonal spread offers a wider range of profitability for the investor or trader.

Structure

A diagonal spread is constructed by selling near-term options and buying longer-term options with different strikes. On top of this, the spread uses different expiration dates on each option contract.

Main Components

• Different strikes and expiration dates are used in the diagonal spread.
• The same underlying asset is used.
• These spreads are structured with a directional bias in mind.
• Diagonal spreads can be set up for a net debit or a net credit.

Ideal Market Conditions

The diagonal spread does well when there’s an expectation that the underlying asset is going to move in either direction, but it isn’t going to be a move of great magnitude, and there aren’t going to be any sharp or sudden movements that create volatility. Diagonal spreads do well initially in range-bound or sideways markets when traders are first entering the spread, but they do benefit over time from lessening volatility, particularly in the case of the short option.

Profit Drivers

• Time Decay: The short-term option loses value as it gets closer to the expiration date, and this time decay can benefit the diagonal spread so long as the underlying asset doesn’t move significantly in either direction.
• Volatility: When there are changes in vega (IV changes), this can have a beneficial effect on the diagonal spread. Some setups are designed around profiting from increased implied volatility, and it is usually the long-term option that needs a higher vega level than the short call.
• Price Movements: Price movement toward a long strike can be beneficial to traders who are using a diagonal spread. The long-term option will gain value if the underlying asset moves in the trader’s desired direction, and at the same time, the short-term option loses value. As a result of the difference between the long and short options, the net effect can have a positive and profitable effect on the spread.

Risks and Adjustments

The maximum loss scenario using a diagonal spread is limited to the net cost of the spread or the debit paid to enter the position. Although this makes a diagonal spread a limited-risk strategy, there are a few other risk factors to consider. These are the conditions that cause the trader’s spread to fall through or not be as successful as it could be.

Main Risks

• IV Skew: If there are major IV changes in the short-term option, this can hurt the spread’s overall profit potential.
• Time Decay: Although this factor can benefit the diagonal spread, it can also work against it, achieving a harmonious, profitable outcome for the trader. This particularly pertains to time decay in the long option, where the spread benefits from decay in the short option. Time decay in the long option can affect the spread’s profitability.
• Sharp Price Movements: The diagonal spread can be affected by sudden price movements in the underlying asset that move unfavorably against traders. These sharp price movements can have a disastrous effect on a spread where the short option is exercised.
• Overpaying to Set Up the Spread: The potential profit can be much lower than expected if the trader overpays for the options contracts they’re entering to form the spread to begin with. Traders need to look for entry points that will expand their profit margin, but that can take some research in historical price data.
• Early Exercise: Complications can arise for traders using a diagonal spread if the short option is exercised early. This can lead to the trader having to increase their management of the position to keep losses to a minimum or lock in profits earlier than expected.

Use Case Scenarios

For the sake of a clear example concerning the diagonal spread, let’s look at a scenario where a trader or investor is using a spread that has a bullish market outlook. They envision that the underlying asset is going to go up in value. To set up a diagonal spread that is going to profit them, the trader would sell a call option with a strike price of $100 that has an expiration date that is set for one week after the sale. At the same time, they would buy one all option for $105 and have an expiration date that would be set for one month after the purchase.

Ratio Spreads Explained

The ratio spread is the odd duck of the trio of spreads we are covering in this guide. It’s a more complex strategy where traders are buying and selling unequal amounts of contracts that have different strike prices, but mainly focus on the same underlying and expiration. These spreads can be structured to be a debit or a credit, and the profit/loss outcomes will often be quite different if you look at the potential outcomes that could occur in each direction.

Structure

You usually see a common structure of a 1:2 ratio where traders are buying one contract and selling two. Another common way to set up a ratio spread is using a ratio of 1:3 (buying one contract and selling three). Ratio spreads can be structured using calls or puts. How the trader determines the ratios and strike used ultimately goes back to their market outlook on the movement of the underlying asset’s price.

The heart of the ratio spread’s structure is an unequal number of long and short options (e.g., 1 long, 2 short). The smaller number in the ratio represents the long option, while the biggest number signifies the short option. Ratio spreads can also be built as debit or credit spreads.

Ideal Market Conditions

The ratio spread performs best where there is a slight direction in the markets. In other words, the underlying asset is expected to exhibit moderate movement in the price of the stocks being traded, and it’s these conditions where using a ratio spread can be beneficial. Use a call ratio spread when you’re feeling neutral to slightly bullish, or a put ratio spread when you’re feeling neutral to slightly bearish.

Ratio spreads are the ideal choice for a market environment that is stable or characterized by decreasing IV. However, it is important to note that ratio spread should be set up when market conditions have heightened IV because the inflated premiums allow traders to collect more credit.

Profit and Loss Characteristics

If the underlying asset price is at or near the short strike price by the expiration date, the maximum profit for the ratio spread is achieved, but it all depends on what kind of strike price and ratios were used when setting up the trade. The optimum profitability occurs when the spread remains within the desired range and moves in the intended direction (it could be up, down, or remain the same).

The maximum loss scenario occurs when the price of the underlying asset moves against the intended position that the trader based the spread around. The losses can be especially substantial if there is a big ratio between the long and short positions. For instance, a ratio of 1:3 would incur a bigger loss than a trade setup that was using a 1:2 ratio. Ratio spreads can be high risk if the underlying moves strongly against the short leg.

Example with Calls and Puts

Traders who have a bullish outlook on the market might set up their ratio spread like this when they’re using a 1:2 setup:

• Buy one call option on AAPL stock at a strike price of $200
• Sell two call options on AAPL stock at a strike price of $205

If the trader is feeling more bearish on the AAPL stock, they would be using put options instead of call options to profit from the stock’s decline.

Side-by-Side Strategy Comparison

Knowing when to use each strategy is paramount to getting the most bang for your buck out of each spread setup. Keep in mind that some of these spreads share similarities that could cater to a certain type of trader, but they’re ultimately three unique approaches for a specific purpose.

When to Use Each Strategy

• Calendar: Time-decay advantage with neutral view
• Diagonal: Moderate directional outlook with flexibility
• Ratio: Higher reward but higher risk with strategic IV exposure

Choosing the Right Strategy

Spread strategies can be used to manage risk as well as tailor options exposure based on your personal market outlook on the movement of the underlying asset’s price. If you are uncertain about when the right time is to use each of the spread strategies we’ve talked about, we’d encourage you to keep reading to get familiar with some of the decision-making factors that can help you choose the right spread for the right scenario.

Decision Factors

• Outlook on Underlying Price Direction: Traders who are feeling neutral on market outlook should use the calendar spread. When there are mild trends in either direction, it is a good idea to use the diagonal spread. Higher conviction trades coupled with a high risk tolerance from the investor constitute the use of a ratio spread.
• Implied vs. Historical Volatility: Rising IV in the markets is a good sign of using either the calendar spread or the diagonal spread. Choosing between those two would require the trader to consider the price direction. However, when IV is falling, it would be a smart move for the trader to use a ratio spread.
• Timeframe Until Catalyst/Event: Another strong consideration for choosing the right spread would be the timeline that the trader has to work with until the event or catalyst arrives. If the event happens within a matter of weeks, the calendar spread is the best move. Anything longer than that makes it appropriate for traders to use either the diagonal or ratio spread.
• Risk Tolerance: Traders who have a low to moderate risk tolerance will be right at home using the diagonal or calendar spread, but those with a high risk tolerance will feel more comfortable with pursuing the ratio spread and its high-risk/high-reward nature.

Pro Tips & Best Practices

As you go forward with implementing and managing the spreads we have talked about in this guide, we’d like you to take these pro tips and best practices forward with you to avoid making a lot of the mistakes that a lot of first-time traders make when using calendar, ratio, or diagonal spreads.

• Manage Early Assignment Risk in Short Legs: The proactive way that traders can avoid the risk of early assignment is to choose short options that have little to no intrinsic value. What this means is that traders should direct their attention to out-of-the-money options where the underlying asset’s price hasn’t been reached yet. This keeps traders out of the trouble of early assignment.
• Adjusting Trades: One way to adjust your spread is to roll out to a different strike price or a further expiration date. This is done by closing out existing legs of the trade and opening new legs that have the updated strikes or expiries. Another technique is taking the positions of an existing calendar or ratio spread and creating a butterfly payoff profile that can manage risk more effectively or adjust the direction bias of the original spread.
• Monitor Greeks: The key to success with trading using spreads is finding ways to benefit from time decay on the short leg of the spread and changes in implied volatility. It is best for traders to closely monitor the Greek symbols Theta and Vega to gain insights on how these changes could impact the value and direction of the underlying asset.

Final Thoughts

Choosing the right spread strategy largely depends on your trading goals and the current market conditions. You can essentially boil down the basics of these time-structure strategies in the following points:

• Calendar Spreads: Best used when traders have a neutral view of the underlying’s future price movements and benefit greatly from the time-decay factor. It uses the same strike, but different expiries. The max profit is centered on the strike, so the prices are rangebound and stable.
• Diagonal: Traders can use this spread to benefit from a moderate directional outlook with flexibility. It uses different expiries and strikes, but offers the trader the ability to speculate on mild market movements in either direction. It has more flexibility and profit potential than the standard calendar spread.
• Ratio: This spread is more complicated than the other two and offers a higher reward to traders, but they come with higher risk that is a result of strategic IV exposure. Ratio spreads can benefit from falling or flat IV and let traders benefit from slight bearish or bullish movements.

Before deciding on the best time-structure strategy, traders and investors should look at the market context before making a final decision. Certain occasions will call for a different strategy, so knowing the differences can make the final decisions that much easier. When in doubt about how to use each of these spreads, it’s best to paper trade to gain some practice before using real money in a live market.

Frequently Asked Questions

Perhaps we missed a few things in our guide on spread strategies. We hope we can plug any of the missing pieces here in the FAQ section. Check out a few of the most common questions from readers and customers on the subject and our answers to these queries. Hopefully, it can give you some additional insights on the differences between calendar vs. diagonal vs. ratio spreads.

What’s Better for Earnings Plays — Calendar or Diagonal?

The diagonal spread ultimately offers the most benefits for the online trader or investor due to its flexibility. Traders can use multiple strike prices, and they can even use directional plays to secure their profits. The calendar spread, on the other hand, can only profit if IV is low and there’s an expectation that it will rise over time.

How Do I Avoid Assignment Risk in Ratio Spreads?

Traders can avoid ratio spread assignments in a few different ways. They can trade strike prices that have little intrinsic value, focusing mainly on out-of-the-money options. Another method is to close positions early before they expire. Still, traders could even take the third option of rolling options to a further expiration date of a different strike when they are currently trading in the money.

Can I Combine These Spreads in a Portfolio?

Yes, multiple spreads can be used in a single portfolio. In fact, doing so helps traders to develop a portfolio that is diverse and well-rounded, allowing it to be resilient when faced with challenges. Traders should feel confident with mixing these spreads across multiple underlyings and expiries to create a strong portfolio that is less prone to market upheaval.

Related Resources & Further Reading

• Option Spreads Guide
• Volatility Guide
• Option Greeks Guide