Diagonal spread
Combines a vertical and a calendar spread. Buy a long-dated option at one strike, sell a shorter-dated option at a different strike. Common in poor-man's covered call setups.
How a diagonal spread works
A diagonal spread buys a longer-dated option at one strike and sells a shorter-dated option at a different strike. It combines the time-decay edge of a calendar spread with a directional lean from the strike difference — hence "diagonal" rather than vertical or horizontal.
The most common construction buys a longer-dated call closer to the money and sells a shorter-dated call further out. The long leg gives you upside exposure with more time to be right; the short leg reduces the cost and decays faster. If the stock drifts up toward the short strike, both effects work together.
Many traders run it as a repeatable structure: hold the long-dated option and sell a new short-dated one against it each cycle, in the manner of a covered call but with an option standing in for the shares. It requires less capital than owning stock, at the cost of an expiry date on the whole position.
Worked example: diagonal spread
XYZ trades at $100 and you are mildly bullish over the next couple of months. You buy the 60-day $100 call for $4.50 per share and sell the 30-day $105 call for $1.50.
The ideal outcome is a stock that climbs to just below the short strike and stops. A move well past $105 still profits but is capped by the short call until it is rolled — the upside is not open-ended while that leg is live.
When a diagonal spread fits — and when it doesn't
- You are mildly bullish over a multi-month horizon and want to reduce the cost of a long call.
- Short-dated implied volatility is elevated relative to longer-dated, so the leg you sell is the expensive one.
- You intend to sell against the long leg repeatedly rather than treat it as a single trade.
- You expect a sharp move up. The short call caps you exactly when the position is working.
- You cannot monitor it. Diagonals need managing at each short expiry, unlike a single-leg position.
- Either expiry is illiquid — two legs across two expiries means four crossings and a lot of slippage.
Common questions about a diagonal spread
Done planning? Log the trade.
Sutekka journals every leg automatically — and shows you the actual P&L when you close it. Free forever.
Start logging — free