Diagonal Spreads: Time Decay With a Direction
Take a calendar spread and slide the two strikes apart. You keep the time-decay engine but add a direction to it, which is why the diagonal is one of the most flexible trades in options.
- How a diagonal spread mixes different strikes and different dates
- Why it is a calendar with a directional lean added
- What you want the stock to do, and what your risk is
- Why diagonals are so flexible
Last lesson, your calendar spread put both legs at the same strike, $200. That kept it purely about time. No direction, no lean, just the clock.
Now make one change. Slide the two strikes apart. The moment you do, your trade picks up a direction, on top of the time-decay engine it already had. That is a diagonal spread, and the small change makes it one of the most flexible trades you can put on.
Slide the Strikes Apart
Apple is at $200, and this time you are gently bullish. You think it drifts up over the next few weeks, but not in a rush.
You buy the 1-month $200 call for $5 a share, your longer-term, lower-strike leg. This is your bullish position, the one that gains if Apple climbs.
You sell the 1-week $210 call for $0.50 a share, a near-term, higher-strike leg. This melts fast (you sold it, so that helps you) and sits above the price, leaving room for Apple to drift up.
Time Decay Plus a Direction
A diagonal runs on two engines at once, and that is the whole point.
Compare it to what you already know. A calendar earns time decay but bets on no direction. A bull call spread bets on a direction but earns no time decay. A diagonal does both: it earns the decay of the near leg you sold, and it gains as Apple drifts up toward your short strike. Two ways to win in one trade.
What You Want to Happen
A bullish diagonal has an ideal script: Apple drifts gently up and sits near $210 as your near-term call expires. Your short call melts to nothing (you keep that), and your longer-term $200 call has gained value from the climb. Best of both worlds.
And like a calendar, you can run it again. Once the near-term call expires, you still own that longer-term call, so you can sell a fresh near-term call against it and keep collecting. That repeating pattern is the heart of some powerful longer-term income strategies built on year-long options, which we cover in the advanced course on LEAPS.
When a Diagonal Fits
- You lean mildly bullish or bearish, not violently
- You want time decay and a direction in the same trade
- You like selling a fresh near-term leg each cycle
- You expect a slow drift, not a sudden jump
- You expect a big, sudden move
- You want one simple, fixed payoff
- You do not want to manage the near leg each cycle
When I was advising clients, the diagonal was the trade that felt like it had a dial. Lean it more bullish or less, collect more decay or less, just by sliding the strikes and dates. Once you are comfortable with calendars and verticals, the diagonal lets you blend them to fit almost any view.
- A diagonal spread uses different strikes and different expiration dates.
- It blends a calendar (time decay) with a vertical (direction) in one trade.
- A bullish diagonal owns a longer-term lower call and sells a near-term higher call.
- It does best on a slow drift toward the strike you sold.
- Your risk is limited to about the net debit, here $450, and you can repeat it each cycle.
Pop Quiz
Three quick questions to lock it in. Pick an answer and the explanation shows up right away.
What makes a diagonal different from a calendar?
A calendar shares one strike. A diagonal slides the strikes apart, which adds a direction on top of the calendar's time-decay engine.
A bullish diagonal does best when Apple does what?
A slow drift up lets the near call you sold melt away while your longer-term $200 call gains value. Decay and direction both pay.
What two trades does a diagonal blend?
The two dates give it a calendar's time decay, and the two strikes give it a vertical's direction. A diagonal is both at once.
Bottom Line
A diagonal spread is a calendar with a direction. By using two strikes and two dates, you earn time decay from the near leg you sold and a directional gain from the strike gap, all while your risk stays limited to what you paid. It is the most adjustable trade you have met so far, a dial you can set to match almost any gentle view.
Next up: Straddles and Strangles. We have spent several lessons getting paid when a stock goes nowhere. Now we flip it completely. Straddles and strangles are how you profit from a big move, when you are sure something will happen but have no idea which way.