Double Diagonal Spread: Selling the Same Strikes Twice in a Range Trade

Most range trades in options come down to one bet: the price stays inside a band and time does the rest. The iron condor is the familiar way to make that bet. The double diagonal spread makes the same bet with one twist. The two protective options you buy sit in a later expiry than the two you sell, so you can sell the inner strikes once, roll them, and sell them again.

That twist adds income and adds moving parts. Below we lay out the four legs, why the structure works, a worked example with hypothetical numbers, how the trade turns into an iron condor halfway through, and the places it tends to go wrong.

What a double diagonal spread is

The Options Playbook describes the setup as four out-of-the-money options:

• Buy a put at strike A, roughly 60 days from expiry (the back month).
• Sell a put at strike B, roughly 30 days from expiry (the front month).
• Sell a call at strike C, in the front month.
• Buy a call at strike D, in the back month.

The price usually sits between B and C when you put the trade on. In plain terms, you’re running a diagonal put spread and a diagonal call spread at the same time. If you’ve read our explainer on the diagonal spread, this is simply two of them, one on each side of the market.

A useful way to picture it comes from Options Trading IQ: think of an iron condor, then push the two long options out to a later expiry. The short strikes stay closer to the current price than the long strikes, just like a condor. The put side benefits if prices rise, the call side benefits if prices fall, and the two cancel each other out, so the position as a whole doesn’t lean in either direction.

Why the double diagonal spread earns money

The engine is time decay. Front-month options lose time value faster than back-month options, so you sell the ones that melt quicker and own the ones that hold their value longer. Options Trading IQ puts it the same way: in calendars, diagonals and double diagonals, the shorter expiry is always the one sold, and that is the only way to get time decay working for you.

The long options at A and D are there for protection. If the market moves much more than expected in either direction, they cap how much the short options can hurt you. That’s what separates this from simply selling a strangle.

You are not betting on direction. You are betting that the market stays in a band long enough for you to sell the same strikes twice.

Here is the part that makes it different from a condor. When the front-month options are close to expiry, and the price is still between B and C, the Playbook’s plan is to buy those short options back and sell a fresh put at B and a fresh call at C, this time in the same expiry as your long options. That’s a roll. Once it’s done, all four legs share one expiry and the position is a plain iron condor. The Playbook notes that some traders like this over a longer-dated condor because they collect premium on the B and C strikes twice.

Credit or debit at the start

Ideally you’d open the trade for a net credit. Often you can’t. The front-month options you sell carry less time value than the back-month options you buy, so the Playbook says you may have to open for a small net debit and recover it when you sell the second round of options. Plan for that rather than being surprised by it.

A worked example with hypothetical numbers

Let’s walk through one. Everything here is made up for illustration: a hypothetical index called XYZ trading at 24,000, with premiums quoted in index points. Real premiums depend on volatility, time and interest rates on the day.

Opening the trade (front month about 30 days, back month about 60 days):

• Buy the back-month 23,400 put (strike A) for 150 points.
• Sell the front-month 23,600 put (strike B) for 110 points.
• Sell the front-month 24,400 call (strike C) for 105 points.
• Buy the back-month 24,600 call (strike D) for 140 points.

You pay 150 + 140 = 290 points and collect 110 + 105 = 215 points. That’s a net debit of 75 points.

Risk at this stage. The Playbook’s rule for a trade opened at a debit is strike B minus strike A plus the debit. Here that’s 23,600 minus 23,400, which is 200, plus 75, giving roughly 275 points. Multiply by the lot size the exchange sets for the contract to get the rupee figure. Treat this as an approximation, because the back-month options still have time value left when the front month expires.

The roll. Say XYZ is at 24,050 a few days before the front-month expiry. Both short options are well out of the money and nearly worthless. You buy them back for 5 points combined, then sell a new 23,600 put for 90 points and a new 24,400 call for 85 points, both in the back-month expiry. That second round brings in 175 points.

Where you stand after the roll. You now hold an iron condor: long 23,400 put, short 23,600 put, short 24,400 call, long 24,600 call, all in one expiry. Your total premium is 175 collected, minus the 75 debit, minus the 5 spent closing the first shorts, which leaves a net credit of 95 points.

• Maximum profit: 95 points, if XYZ finishes between 23,600 and 24,400 and every option expires worthless.
• Maximum loss: the 200-point width of either wing minus the 95-point credit, so 105 points.
• Breakeven at expiry: 23,600 minus 95, which is 23,505 on the downside, and 24,400 plus 95, which is 24,495 on the upside.

Notice what the roll did. Before it, the worst case was about 275 points. After it, the worst case dropped to 105, because the second round of premium came off the risk. That’s exactly the Playbook’s point that any extra premium from the second sale gets deducted from total risk. It’s also why you can’t pin down the maximum profit on day one. You don’t know what the second round of options will fetch until you sell them.

What the Greeks are doing

Time decay works for you through the whole trade. Volatility is more nuanced, and the Playbook breaks it into phases.

• Before the roll: you want the price to stay put, but a rise in implied volatility around front-month expiry helps, because it means more premium when you sell the second round.
• After the roll, price near the middle: you want volatility to fall. Lower volatility shrinks the value of every option, and you want them all to expire worthless.
• Price near or beyond a long strike: now a rise in volatility helps, since it lifts the long option close to the money more than the short options further away.

For more on why short-dated options lose value faster, see our piece on theta decay in options trading.

Two flavours: traditional and double long

Options Trading IQ compares two versions built on SPX at the same time. The traditional double diagonal is the one we described: short strikes closer to the money, long strikes further out. The “double long diagonal” flips which strikes are bought and sold, so the long options sit closer to the money.

The differences follow from that. In their illustration the traditional version cost a net debit of $151 and the double long version cost $920, because options closer to the money are more expensive. The double long version carries more vega, which can suit a calm, low-volatility market where a rise in implied volatility is possible. The traditional version carries more theta, since its short options are nearer the money and decay faster. In their example the two came out with a broadly similar reward-to-risk of roughly two to one. Neither is clearly better. It depends on whether you’d rather be paid by time or by a pickup in volatility.

Managing the trade when the market moves

This is where most of the work is. Sitting between B and C is easy. Getting pushed toward one side is not.

Watch the final week. The Playbook warns that if a front-month short option is in the money during the last week before expiry, it gains value much faster than the back-month option you own. If it looks like a short leg will finish in the money, consider rolling before that last week arrives.

Close one side. Options Trading IQ shows a simple adjustment. When SPX fell through the short put strike in their example, they closed the losing put diagonal and kept the call diagonal, which benefits from the fall, still open. An alternative is to close whichever diagonal is further from the price and keep the one nearer the money for its higher decay.

Don’t carry short options through expiry. The Playbook notes most traders buy back the front-month shorts before they expire, to avoid a gap in price between one session’s close and the next open.

The roll is the trade. If you aren’t comfortable rolling short options under pressure, this structure will feel like four problems instead of one.

Stocks or indices?

The Playbook suggests some traders prefer index options for this strategy, since moves in individual stocks inside an index tend to offset one another and indices have historically been less volatile than single stocks. If you go the index route, check bid-ask spreads on both expiries before you trade, because four legs means paying the spread four times, and a roll adds two more.

The Playbook also flags early assignment on short options as a risk to manage. Before you trade, confirm with your exchange’s contract specifications how and when the options you’re using can be exercised.

Who should run it

The Playbook is blunt: because of the risk if the stock falls sharply, it classes the double diagonal as a strategy for the most advanced traders only. We agree. You need to be comfortable with:

• Pricing options across two expiries, since break-even points can only be estimated with a pricing model before the front month expires.
• Rolling short options, sometimes in a hurry.
• Sizing the trade so that the worst case before the roll, not just after it, is an amount you can lose.
• Keeping track of costs on four legs plus the roll.

If you’re newer to multi-leg trades, start with a single double calendar spread or a plain iron condor on paper first. Our options trading for beginners in India guide covers the building blocks.

A quick checklist before you place it

• Price roughly midway between strikes B and C, unless you want a deliberate tilt.
• Front-month shorts and back-month longs, all four out of the money.
• Know your worst case before the roll and after it, in rupees, using the actual lot size.
• Decide in advance where you’ll roll, where you’ll close one side, and where you’ll exit.
• Check liquidity in both expiries.

A double diagonal is not a set-and-forget trade. It rewards a quiet market and a trader who shows up at the roll. Get those two things right and you get paid twice on the same strikes. Get them wrong and the protective wings are all that stand between you and a full-width loss.

Disclaimer: This article is for educational purposes only and is not investment advice. XYZ and all prices, premiums and outcomes in the example are hypothetical. Options trading involves substantial risk and is not suitable for everyone. Consult a SEBI-registered investment adviser before making investment decisions.