What is a Butterfly Spread?

A butterfly spread is a neutral strategy that profits when the stock stays near a specific price at expiry. It combines a bull spread and a bear spread, creating a position with very low cost and defined risk.

The maximum profit occurs when the stock closes exactly at the middle strike at expiry. The maximum loss is limited to the net premium paid.

How to Construct a Butterfly

Let me show you with Nifty example. Suppose Nifty is at 24,500 and you expect it to stay around 24,500 at expiry.

  1. Buy Nifty 24,300 Call at ₹250
  2. Sell 2 Nifty 24,500 Call at ₹180 each (total ₹360)
  3. Buy Nifty 24,700 Call at ₹120
  4. Net debit: ₹10 per share (₹500 per lot)

Profit and Loss Profile

  • Maximum Profit: ₹10,000 per lot (occurs at 24,500)
  • Maximum Loss: ₹500 per lot (net premium paid)
  • Break-evens: 24,310 and 24,690

The risk-reward ratio is incredible — you can make 20x your risk if Nifty closes exactly at 24,500.

Long vs Short Butterfly

A long butterfly profits from low volatility (stock stays near middle strike). A short butterfly profits from high volatility (stock moves beyond the wings). Use long butterfly when you expect consolidation and short butterfly when you expect a breakout.

When to Use Butterfly Spread

  • You expect the stock to stay in a narrow range
  • You want a high reward-to-risk ratio
  • Implied volatility is high (making the sold options more valuable)
  • You have a specific target price in mind

SEBI Disclaimer

This article is for educational purposes only. Options trading involves substantial risk of loss.

The Breakeven Math, Precisely

A long butterfly is three legs on one side, ATM, with a common strike sequence. The breakevens are arithmetic and worth committing to memory:

  • Constructed with strikes A (lower), B (middle) and C (upper), equal spacing W.
  • Lower breakeven = B - max(credit) when built for credit, or B - net debit for a debit fly.
  • Upper breakeven = B + the same distance; the payoff peaks exactly at the middle strike B.

The tradeoff is honest: you pay a defined max loss (the difference between current premium and intrinsic drift) to win a defined max gain, with both boundaries knowable before entry. That predetermination is the fly's entire appeal.

Delta-Neutral Entry Discipline

A long fly bought at its true ATM creed should be roughly delta-neutral at the middle strike: neither bullish nor bearish within the wings. Deviation from neutral marks a skew:

  • If the fly carries positive delta, you are paying to be long; an options trader who does not know why must not.
  • Skewed butterflies (weighted flies) consciously accept directional tilt; state it as a thesis, not an accident.
  • Check neutrality again after entry; the fly drifts as the underlying moves, and a fly that was neutral at entry is directional by Thursday afternoon.

Adjusting Into a Broken Wing

When the middle strike gets run through, the standard rescue is to convert toward the broken wing:

  1. Roll one wing out: buy the far leg closer or sell a nearby leg, shifting breakevens toward the price.
  2. Accumulate the credit inside on each roll and cap total surgery to two adjustments; cost three adjustments in a fast market and you have recycled a defined risk into an undefined expense.
  3. If the underlying has genuinely broken regime, flatten and take the defined loss; a fly was never a trending instrument.

Pin Risk at Expiry

An in-the-money fly held to Friday settlement faces pin risk: the underlying settles exactly at B and assignment on the short legs triggers a next-day margin surprise.

  • Close the fly before 15:15 on expiry day unless you intend assignment mechanics explicitly.
  • If unintentional assignment happens, sell the forced units immediately at Monday open; holding a pin-position through the weekend is a lottery with a defined downside that started defined and ended not.

A Nifty Fly Worked in Round Numbers

Nifty at 25000, 30 DTE, IV calm:

  • Buy 24800 call at 350, sell 2x 25000 call at 190 each, buy 25200 call at 75.
  • Net debit about 45 points, max gain near 155 points if the index settles at 25000, max loss the 45 debit.
  • Breakevens at roughly 24955 and 25045: the market needs only a half-percent ping to make money.

Butterflies reward knowing what a move is and isn't: a rangebound drift to the middle strike pays full talk-time yield; a breakout beyond either wing pays less than a straddle would have. Scale your fly to a forecasted range, not to hope, and let the breakeven math, not the chart, tell you when it has already won.