Double Diagonal Spread Strategy

What is a Double Diagonal Spread?

A Double Diagonal Spread is a hybrid options strategy that combines features of a calendar spread and a diagonal spread, implemented with both puts and calls. The core idea is to buy a longer-dated straddle (buying a call and a put at the same strike and expiry) and simultaneously sell a shorter-dated strangle (selling a call and a put at different strikes).

The result? A position that can benefit from time decay in the short-term options and volatility in the longer-term options—making it ideal for a trader who expects the underlying stock to stay within a specific range over the short term.

Constructing a Double Diagonal Spread: An Example
Let’s consider a hypothetical stock, XYZ, currently trading around ₹100.

To create the double diagonal spread:

Sell 1 XYZ 95 Put (28 days to expiry) at ₹1.30

Buy 1 XYZ 100 Put (56 days to expiry) at ₹3.80

Buy 1 XYZ 100 Call (56 days to expiry) at ₹4.00

Sell 1 XYZ 105 Call (28 days to expiry) at ₹1.50

Net Debit = ₹(3.80 + 4.00 - 1.30 - 1.50) = ₹5.00

This ₹5.00 is the maximum potential loss (excluding brokerage and taxes), and it's the cost to enter the position.
 

Why Use a Double Diagonal Spread?

The main objective of this strategy is to profit from neutral price movement. Ideally, the stock should remain between the two strike prices of the short strangle (₹95 and ₹105 in our example) as expiration of the short-term options approaches.

Unlike a regular strangle, where the losses can be theoretically unlimited, the double diagonal spread limits both risk and reward. It offers a more conservative approach, especially in volatile markets where traders expect the price to stabilize in a range.

Profit Potential: Where’s the Sweet Spot?
The strategy earns the maximum profit when the stock price is exactly at the strike price of either the short call or the short put at the time of the short strangle’s expiration. Why?

Let’s take the case when the stock is at ₹105 at the expiry of the 28-day options:

• The short call at 105 expires worthless.
• The long call at 100 is in-the-money and still has time value because it has 28 more days to expiration.
• The put side is also profitable, as the short 95 put expired worthless while the long 100 put still retains value.
• The value difference between the long and short options gives you the profit, minus the net debit of ₹5.00.

Here’s a summary table for possible outcomes:

*Long straddle values are estimated using Black-Scholes model with assumed volatility of 30%, 28 days to expiration for the long options, and 1% interest rate.
 

Maximum Risk and Breakeven Points

As noted earlier, the maximum risk is the net cost of entering the position, i.e., ₹5.00 in our case. This risk materializes if the stock ends up at ₹100 (the strike of the straddle), and the value of the long straddle erodes due to time decay.

Breakeven:

While exact breakeven prices can't be determined upfront due to the dependency on volatility, they typically lie just outside the short strike prices. In our case, breakeven may occur slightly below ₹95 and above ₹105, depending on the premium received and long straddle's remaining value.
 

When Should You Use a Double Diagonal Spread?

This strategy suits you best when:

• You have a neutral view on the underlying stock.
• You expect the price to stay within a defined range for the short term.
• You want limited risk with a defined loss.
• You believe implied volatility will stay steady or rise for the long-term options.

Greeks and Sensitivities

Delta: Initially close to zero. But at expiry:

If stock is at ₹105 (short call strike), delta shifts to around +0.50.
If stock is at ₹95 (short put strike), delta becomes -0.50.

Theta: Time decay works in favor due to the short strangle.

Vega: The strategy is vega positive, meaning it benefits from an increase in volatility of the long options.

Key Benefits and Limitations

Pros:

• Defined risk and limited loss.
• Can be adjusted as market moves.
• Profits from time decay and volatility rise.

 Cons:

• Complex to manage for beginners.
• Profit potential is modest.
• Requires precise trade execution and good pricing.
   

Final Thoughts

The double diagonal spread is a well-rounded options strategy for seasoned traders who are comfortable navigating advanced trades. It’s particularly attractive during earnings seasons or sideways markets where volatility spikes but the underlying doesn’t move significantly.

For investors like you, Dhiraj, who are exploring deeper financial strategies or writing analytical content for a trading blog, this strategy offers strong educational value and application.

Stay disciplined, manage your exits, and ensure you enter such spreads at optimal prices using limit orders. And as always, practice on a paper trading account before implementing it with real capital.