Options Chain
How to read and interpret an options chain
What Is an Options Chain?
An options chain is a table listing all available option prices for a specific underlying asset at a specific expiration date. It contains a list of every available call and put with its strike, bid-ask prices, volume, open interest and other data. The options chain is the "price menu" for options: it shows every contract available to choose from. Each row typically represents a different strike, with columns for both calls and puts. The options chain is the fundamental tool any trader uses to identify which contracts to trade. Without an options chain you could not see option prices at all, so it is absolutely central to everything in options trading.
Key Components of an Options Chain
An options chain typically shows the following for each strike. The strike price is the exercise price. Bid and Ask are the current buy and sell prices. Volume is how many contracts traded during the day. Open interest is how many contracts remain open and unclosed. Implied volatility (IV) is the expected volatility implied by the option’s price. Change is how the price has moved during the day. The greeks (delta, gamma, vega, theta) show the option’s sensitivity to changes in various factors. Some data providers also show the probability that the option expires ITM. Most platforms let you click an option in the chain to send an order directly.
How to Read the Price Distribution
Looking at an options chain, you can see clearly how prices change with the strike. Call prices decrease as the strike rises; a $100-strike call costs more than a $110-strike call. Put prices increase as the strike rises; a $120-strike put costs more than a $100-strike put. At the ATM strike (where the current price sits), call and put prices should be roughly equal for a European option, though they can differ slightly for American options. As you move away from the ATM strike toward the extremes, prices fall dramatically. Deep OTM options can cost only cents, while deep ITM options can be worth nearly the underlying price less the strike. Watching the curvature of this price structure tells you about implied volatility and skew.
Interpreting Open Interest and Volume in the Chain
Open interest and volume vary significantly across the chain. Typically, open interest is highest at ATM strikes and falls toward the extremes. High open interest at a particular strike indicates a lot of accumulated activity at that level and probably good liquidity, with tight spreads. High volume at a specific strike during the day indicates that many traders are trading that contract today. You can spot interesting patterns in a chain: if you suddenly see very high open interest at a specific strike, it can mean an institution has just taken a large position. Volume heavily concentrated in a few specific strikes can point the same way. Volume and open interest patterns often coincide with important technical support and resistance levels.
Using the Chain to Make Trading Decisions
When choosing which option to trade, the chain provides critical information. First, you can see the bid-ask spread; prefer options where the spread is tight (a sign of liquidity). Second, you can see open interest and volume; prefer options with meaningful open interest. Third, you can see IV; compare it against this option’s historical average to judge whether it is expensive or cheap. Fourth, you can compare the greeks to see what is sensitive to what, which helps you pick the option that best matches your view. Fifth, you can see the probability of expiring ITM (where provided), which helps you understand the odds of success. Sixth, you can see patterns in the data — jumps in volume or open interest — that point to where institutional money has positioned. Many traders simply start at the ATM strike and adjust from there.