when volatility rises the price of both options tends to increase this means that the value of the long call option would increase but at the same time the value of the short call option would also increase given that this options trading strategy is long one option and short another option the effects of a change in volatility on both options can offset each other to a large extent 
in the language of options this is often referred to as a near zero vega vega measures the sensitivity of an option s price to changes in volatility a near zero vega implies that the price of the bull call spread changes very little when volatility changes assuming other factors remain constant it should be noted that the bull call spread is not completely immune to changes in volatility the exact impact can depend on other factors including how far the options are in or out of the money and how much time is left until expiration the impact of time on a bull call spreadthe impact of time on a bull call spread also known as time decay or theta is complex because the strategy involves two options a long call and a short call both of these options have different responses to the passage of time the time value portion of an option s total price decreases as expiration approaches but the overall impact of time decay on a bull call spread is dependent on the relationship of the stock price to the strike prices of the spread if the stock price is halfway between the strike prices then time erosion has little effect on the price of a bull call spread because both the long call option and the short call option decay at approximately the same rate for the long call option in a bull call spread time decay is detrimental as time passes all else being equal the value of the option that is bought decreases this is because the option has less time to make a profitable move thus it is less valuable if the stock price is near or below the strike price of the long call option the call option with the lower strike price then the price of the bull call spread decreases with the passing of time and would therefore lose money this happens because the long call is closest to the money and decreases in value faster than the short call option for the short call option in a bull call spread time decay works in favor of the trader as time passes the option that was sold decreases in value which is beneficial because the trader has the obligation under that option if the short call option expires worthless the trader keeps the entire premium received from selling it however if the stock price is near or above the strike price of the short call option the call option with the higher strike price then the price of the bull call spread increases with the passage of time and would therefore make money this happens because the short call option is closer to the money and decreases in value faster than the long call the impact of the underlying s price change in a bull call spreadthe price change of the underlying asset has a significant impact on a bull call spread a bull call spread strategy profits when the price of the underlying asset rises if the price of the underlying asset rises significantly and is above the strike price of the short call option at expiration the strategy reaches its maximum profit this is because the long call option increases in value while the short call option is offset by the increase in the underlying asset s price on another note if the price of the underlying rises moderately and is between the strike prices of the long call option and short call option at expiration the strategy will still profit but not as much as in the scenario above the long call option increases in value but the short call option also starts to gain in value which reduces the overall profit finally if the price of the underlying asset falls or does not rise significantly the bull call spread strategy will incur a net loss if the price is below the strike price of the long call option at expiration both options would expire worthless and the loss is limited to the net premium paid to establish the spread other factors to consider in a bull call spreadtraders consider several other factors these include it should be noted that while bull call spreads can limit risk as the maximum possible loss is the initial cost of the spread they also cap potential profits traders weigh these factors and consider their risk tolerance and market outlook before employing this strategy 