Butterflies and Broken-Wing Butterflies

A butterfly is a three-strike structure: long one wing, short two body strikes, long the other wing. Opened for a small net debit. Max profit if the underlying lands exactly at the body strike at expiration; max loss is the debit paid. Defined-risk on both sides.

Butterflies are used as pinning bets — low-cost trades that pay a multiple of the debit if the underlying pins at a specific strike. They're also useful as defined-risk directional bets when the trader has a specific target price in mind. The broken-wing variant adjusts the structure to eliminate downside risk on one side, sometimes producing a credit position with no loss on the unaffected wing.

This article covers the standard butterfly, the math, the broken-wing variant, the iron butterfly briefly, when these structures fit, and 0DTE-specific dynamics.

The standard butterfly

A standard call butterfly at SPX 5000, with 10-point wings:

• Long 1 × 4990 call ($14 paid)
• Short 2 × 5000 calls ($7 each, $14 collected)
• Long 1 × 5010 call ($2.50 paid)

Net debit per share: $14 − $14 + $2.50 = $2.50, or $250 per butterfly.

The position is opened for $250. If SPX closes at exactly 5000 at expiration, the two short 5000 calls expire worthless, the 4990 long call is worth $10 of intrinsic, and the 5010 long call expires worthless. Net value at expiration: $10 per share × 100 = $1,000 per butterfly. Profit: $1,000 − $250 debit = $750.

If SPX closes well above 5010 or well below 4990, all four positions (counting the doubled short) either fully offset or expire worthless together. The position is worth zero at expiration. Loss: the full $250 debit.

A few mechanical notes:

• The "two" in "short two body strikes" means the short leg has twice the contract count of each wing, not that there are two separate strikes. All three legs sit at three strikes total — one wing, the body (with doubled quantity), and the other wing.
• Equal wing widths is the standard structure. Asymmetric wings produce a broken-wing butterfly (covered below).
• The structure is symmetric around the body strike in both legs and in the payoff shape.

The peaked payoff

The combined payoff of a butterfly is a triangle or peaked tent: flat at the max-loss floor (the debit) at and beyond the wings, sloping up to a peak at the body, sloping back down to max loss on the other side.

Combined P&LLong 4990 callShort 2× 5000 callLong 5010 call

Underlying at expiry$5,000

P&L at spot

$750

Max profit (range)

$750

Max loss (range)

-$250

Net debit

$250

Five regions:

• Below 4990: all calls OTM. Position worth zero at expiration. Loss = $250 debit.
• Between 4990 and 5000: the lower long wing is ITM; the short body legs are still OTM. Position value grows linearly from zero up to the maximum at the body.
• At 5000 (the body): lower wing $10 ITM ($1,000 of intrinsic), shorts exactly at the strike (zero value), upper wing OTM. Position value $1,000; profit after debit = $750.
• Between 5000 and 5010: body shorts ITM and growing (negative for the position), but the upper long wing is now defending. Net position value declines from the peak toward the max-loss floor.
• Above 5010: all three calls ITM. Short losses on the doubled body are fully offset by gains on both long wings, with only the original debit remaining as cost. Loss = $250.

Drag the slider. The peak is sharp — small movements away from 5000 produce meaningful changes in the position's value.

The math

For a standard butterfly:

• Max profit = (wing width × multiplier) − debit paid. Achieved when the underlying ends exactly at the body strike.
• Max loss = debit paid. Achieved when the underlying ends beyond either wing.
• Break-evens = body strike ± (wing width − debit-per-share).

For the example above (10-point wings, $2.50 debit per share):

• Max profit = ($10 × 100) − $250 = $750 per butterfly.
• Max loss = $250 per butterfly.
• Lower break-even = 5000 − (10 − 2.50) = 4992.50.
• Upper break-even = 5000 + (10 − 2.50) = 5007.50.

Risk-reward at entry: $250 risked to make up to $750 — 3:1 in the trader's favor at the body. That ratio is favorable, but the probability of full max profit is low. The underlying has to end exactly at the body at the closing print. Partial profits between the break-evens are more common than full max profits.

The math works on expected value when:

• Most of the time the underlying ends outside the break-evens → small loss (the debit).
• Sometimes the underlying ends between break-evens → small-to-medium profit.
• Rarely the underlying ends at or very near the body → large profit (multiple of debit).

Expected value depends on whether the trader's view of where the underlying will close is accurate enough to compensate for the low full-max-profit hit rate.

The broken-wing butterfly

The standard butterfly has equal wings (10-wide on each side in the example above). Broken-wing variants might use 10-wide on one side and 20-wide on the other.

The structural consequence: the further-OTM wing pays a smaller premium (it's cheaper because it's more OTM), so the total cost drops. With wings spread far enough, the structure can flip to a credit position.

When the broken-wing butterfly is opened for a credit:

• At the body: max profit (similar shape to standard butterfly, offset by the credit).
• On the unbroken (closer) side: max loss = wing width − net credit. Smaller than the standard butterfly because of the credit.
• On the broken (further) side: the position can have zero loss or a small profit if the credit covers the wing width on that side.

A common 0DTE application: a put-side broken-wing call butterfly centered above current spot — expresses a bullish view, pays maximum profit if the underlying rallies to the body, and has no loss if the underlying falls instead.

Iron butterfly, briefly

The iron butterfly has the same payoff shape as a regular butterfly but is built with both calls and puts. Same expiration, same body strike, but the two short body legs are one call and one put (not two of the same type).

Structure at SPX 5000, 10-point wings:

• Long 1 × 4990 put (lower wing)
• Short 1 × 5000 put (body, put side)
• Short 1 × 5000 call (body, call side)
• Long 1 × 5010 call (upper wing)

Opened for a credit. Same peaked payoff. Some traders prefer this structure for the credit-collection framing — collect premium upfront rather than pay a debit, even though the net P&L is the same as a regular butterfly with the same strikes.

For 0DTE retail, iron butterflies and regular butterflies are interchangeable in payoff terms. The choice depends on trader preference and how the broker's commission structure handles multi-leg fills.

When butterflies fit

Butterflies are a less-common 0DTE retail structure than credit spreads or iron condors, but they fit specific situations:

Pinning bets. When the trader has a strong view that the underlying will end at or very near a specific strike. Round-number SPX strikes are common targets because of the dealer-pin dynamics covered in Pin Risk and the Gamma Trap. A butterfly centered at a magnet strike pays a multiple of the debit if the pin holds.

Low-cost directional bets. A butterfly centered well above current spot is a cheap way to express "I think SPX will rally to a specific level by the close" with capped downside. Cheaper than a long call (the short body legs reduce the cost) but with a payoff that only pays at the target strike.

Range trades with concentrated payoff. Narrow butterflies bracket a tight range with high payoff at the body. Some traders use these as more aggressive variants of iron condors when they want the larger max profit and accept the lower hit rate.

Broken-wing for asymmetric views. When the trader has a view ("SPX is more likely to rally than fall today") but wants to limit downside exposure entirely, a broken-wing butterfly built to express that view works as a defined-risk substitute for a long-call position with a different payoff distribution.

The realistic outcome distribution

Butterflies on 0DTE have a low hit rate for full max profit — the underlying rarely lands exactly at the body. The realistic distribution:

• Most days: underlying ends well away from the body → full debit loss (small).
• Some days: underlying ends near the body, between break-evens → small-to-medium profit.
• Occasional days: underlying pins at or very near the body → max profit (multiple of debit).

For 0DTE traders, the same expected-value logic applies as for long calls and puts: the structure can be positive-expected-value if the trader has a real edge on predicting where the underlying will close. Without that edge, the structure pays the variance risk premium to the option sellers on the other side.

0DTE-specific dynamics

Three considerations specific to 0DTE butterflies:

Final-hour gamma at the body. The body of a butterfly is short two ATM-ish options at expiration. Position gamma at the body is high in the final hour — the position's P&L is sensitive to small underlying moves. A butterfly that's near max profit at 3:30pm can lose much of that gain by 4:00pm if the underlying drifts away from the body.

Pin risk applies directly. Whether the underlying closes at exactly the body strike or one tick away can mean the difference between max profit and a partial profit. The closing print determines settlement precisely.

Time-based exit rules apply. As with other 0DTE structures, closing the position by 3:30pm avoids the final-30-minute gamma exposure. Captured profit may be less than the theoretical max, but the realized profit is more certain than the unrealized peak.

Key takeaways

Key takeaways

• A butterfly is a 3-strike structure: long 1 wing, short 2 body strikes, long 1 wing. Opened for a small debit. Max profit at the body; max loss = debit paid.
• Max profit = (wing width × multiplier) − debit; max loss = debit. Risk-reward at entry is favorable but the probability of full max profit is low.
• The broken-wing variant uses asymmetric wings to eliminate downside on one side — often opened for a credit, with zero loss on the broken side.
• Iron butterfly is the same payoff shape built with mixed calls and puts, opened for a credit. Mechanically equivalent to a regular butterfly at the same strikes.
• Butterflies fit pinning bets, low-cost directional bets, and concentrated-range trades. They live in the rare-but-large-payoff end of the spectrum and depend on the trader having a real edge on where the underlying will close.