A butterfly strategy is an option strategy using multiple puts and/or calls to make a bet on future volatility without having to guess in which direction the market will move. The long butterfly spread is a three-leg strategy that is appropriate for a neutral forecast when you expect the underlying stock price to change very little over the life of the options.
For example:A long butterfly strategy is constructed from three sets of either puts or calls having the same expiration date but different exercise prices. For example, with the underlying asset trading at 100, a long butterfly strategy can be built by buying puts at 95 and 105, and selling twice as many puts at 100, same can be done with calls. If the underlying does not change price by expiry, the puts at 95 and 100 will expire worthless, and the puts at 105 will be worth 5 (from 105-100). If the underlying is greater than 105 at expiration, all the puts expire worthless, and the initial cost of the butterfly is the amount of the loss. If the underlying is less than 95 at expiration, the gain from the purchased put at 105 will offset the losses from the shorted puts at 100, and the loss is again limited to the initial cost of initiating the butterfly strategy. In essence, this is a limited-risk, limited-gain approach to shorting the volatility of the underlying, as the maximum profit comes when the underlying has no volatility at all.....
When To Use Butterfly Spread?
One should use a Butterfly Spread when one expects the price of the underlying asset to change very little over the life of the option contracts.
When a butterfly spread is implemented properly, the potential gain is higher than the potential loss, but both the potential gain and loss will be limited.
The total cost of a long butterfly spread is calculated by multiplying the net debit (cost) of the strategy by the number of shares each contract represents. A butterfly will break-even at expiration if the price of the underlying is equal to one of two values. The first break-even value is calculated by adding the net debit to the lowest strike price. The second break-even value is calculated by subtracting the net debit from the highest strike price. The maximum profit potential of a long butterfly is calculated by subtracting the net debit from the difference between the middle and lower strike prices. The maximum risk is limited to the net debit paid for the position.
Butterfly spreads achieve their maximum profit potential at expiration if the price of the underlying is equal to the middle strike price. The maximum loss is realized when the price of the underlying is below the lowest strike or above the highest strike at expiration.