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The expected move: the market's guess, and how sellers use it

The expected move is the market's rough guess of how far a stock might travel by an expiry date. You can read it from the at-the-money straddle price or work it out from implied volatility. Sellers use it to see where a strike sits compared with that guess.

Options guide · 8-minute read · Updated 2026-10-27

The short answer

The expected move is the size of move, up or down, that option prices imply by a given expiry. Two quick ways to find it:

1. The straddle price. Add the at-the-money call and put prices together. That sum is roughly the market's guess of the average move.
2. The IV formula. Stock price × Implied volatility × √(days to expiry ÷ 365). That gives a one-standard-deviation move: a range the stock stays inside about two times in three, if the market's guess is right.

Neither is a forecast of direction. It's how far, not which way.

Method one: the straddle

A straddle is a call and a put at the same strike and expiry. Buying one pays off if the stock moves a lot either way. So its price is the market's price for "how much will this move?"

A made-up stock, XYZ, trades at $50. With 30 days left and IV at 30%, a model gives roughly:

• $50 call: $1.80
• $50 put: $1.65
• Straddle: $3.45

So the market is pricing a move of about $3.45, or about 7%, either way by expiry. Some traders multiply the straddle by about 0.85 to tighten it; others use it as is. Both are rough.

Your broker may show this number directly. Many platforms list an "expected move" next to each expiry on the Options chain.

Method two: the IV formula

Expected move ≈ price × IV × √(days ÷ 365).

For XYZ: $50 × 0.30 × √(30 ÷ 365) = $50 × 0.30 × 0.287 ≈ $4.30.

That's a one-standard-deviation move. If the market's IV is right and moves follow the usual bell curve, XYZ ends between about $45.70 and $54.30 roughly 68% of the time. It ends outside that range roughly one time in three.

The two methods give different numbers ($3.45 vs $4.30) because they measure slightly different things. The straddle is closer to the average move. The formula gives the one standard deviation edge. Pick one and use it the same way every time.

Why the square root matters

Moves don't grow in a straight line with time. Four times the days gives about twice the expected move, not four times.

That's why a 7-day option on a jumpy stock can still be risky. The expected move is smaller, but so is the premium, and there's no time to recover.

Using it to place a strike (an illustration, not a trade idea)

Sellers often compare their strike with the expected move.

• Inside the move (closer than $4.30 away): more premium, higher odds of being tested.
• Near the edge: roughly a 0.15 to 0.20 Delta, depending on the stock.
• Well outside: small premium, lower odds, but a big move still reaches it.

You decide to sell a 30-day put right at the low edge of XYZ's one-standard-deviation range ($45.70). You pick the $46 put, just inside it, for about $0.35 and collect $35. Your broker sets aside $4,600.

Where the expected move misleads

• Earnings and big events. Before a report, the straddle for the expiry just after earnings jumps. That's the market pricing the gap. Compare the move with what the stock did on past reports, if you can find them on your broker's earnings history.
• Fat tails. Real stocks have big days more often than the bell curve suggests. A move of two or three standard deviations is rare, not impossible.
• Direction. The expected move is symmetrical. Stocks often fall faster than they rise, which is part of why puts tend to cost more than calls at the same distance.
• It's a snapshot. If IV rises tomorrow, the expected move grows. See vega and IV for option sellers.

How this fits the wheel

In the wheel strategy, the expected move is a quick sanity check on each strike:

1. For a cash-secured put: is your strike inside or outside the move? Would you be happy owning the shares if the stock fell the full move and then some?
2. For a covered call: is the strike inside the move? If so, there's a good chance you'll be called away. Is that price fine with you?
3. Across trades: compare the premium to the move. A big premium on a big expected move isn't richer. It's just bigger.

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