Option Chain
An option chain is one of the most valuable tools available to an options trader. Every trading decision in the options market begins with understanding the information displayed in the option chain. Rather than being just a list of option contracts, it provides a complete snapshot of the market by displaying available strike prices, option premiums, open interest, trading volume, bid and ask prices, implied volatility, and several other important data points. Learning how to read an option chain is a fundamental skill because it helps traders identify trading opportunities, evaluate market sentiment, and select appropriate option strategies.
Whenever a trader decides to trade options, the first step is usually to open the option chain of the chosen underlying asset. Whether the underlying asset is an individual stock, an index such as Nifty or Bank Nifty, or another derivative instrument, the option chain presents all available call and put option contracts for different strike prices and expiration dates. Instead of searching for individual contracts separately, traders can compare multiple strikes simultaneously and make better-informed decisions.
At first glance, an option chain may appear overwhelming because it contains numerous columns filled with numbers that change continuously during market hours. However, once each column is understood individually, the information becomes much easier to interpret. Every figure displayed in the option chain provides valuable insight into market activity and helps traders evaluate the attractiveness of different option contracts.
An option chain is generally divided into three sections.
The **left side** displays information related to **Call Options**.
The **centre** contains the available **Strike Prices**.
The **right side** displays information related to **Put Options**.
This layout allows traders to compare call and put options at the same strike price quickly and efficiently.
One of the most important elements displayed in an option chain is the **strike price**.
The strike price represents the predetermined price at which the option holder has the right to buy or sell the underlying asset. Every available strike price has its own call option and put option, allowing traders to choose contracts that match their market expectations.
For example, if the Nifty Index is currently trading at **24,800**, the option chain may display strike prices such as **24,700**, **24,750**, **24,800**, **24,850**, and **24,900**.
Each strike price will have its own call option and put option with separate premiums and market activity.
The strike price closest to the current market price is generally referred to as the **At the Money (ATM)** strike.
Strike prices below the market price become **In the Money (ITM)** for call options and **Out of the Money (OTM)** for put options.
Similarly, strike prices above the market price become **Out of the Money** for call options and **In the Money** for put options.
Understanding this relationship helps traders select contracts that best align with their strategy and risk tolerance.
Another important column in the option chain is the **Last Traded Price (LTP)**.
The LTP represents the most recent premium at which the option contract was traded in the market.
Since option premiums change continuously throughout the trading session, the LTP provides traders with the latest available market value of the option.
By comparing LTPs across different strike prices, traders can identify which contracts are relatively expensive or inexpensive and evaluate potential trading opportunities.
The option chain also displays the **Bid Price** and **Ask Price**.
The **bid price** represents the highest price that buyers are currently willing to pay for an option contract.
The **ask price**, sometimes referred to as the offer price, represents the lowest price at which sellers are willing to sell the option.
The difference between these two prices is known as the **bid-ask spread**.
A narrow bid-ask spread generally indicates high liquidity because buyers and sellers are actively participating in the market.
A wide spread often suggests lower liquidity, making it more difficult to enter or exit positions efficiently.
Professional traders usually prefer highly liquid contracts because they reduce transaction costs and improve trade execution.
Another essential piece of information displayed in the option chain is **Volume**.
Volume indicates the total number of option contracts traded during the current trading session.
Higher trading volume reflects greater market participation and usually indicates that the option contract is actively traded.
Options with strong volume often provide better liquidity, smaller bid-ask spreads, and smoother order execution.
However, volume reflects only today's trading activity and should not be confused with another important metric—**Open Interest**.
**Open Interest (OI)** represents the total number of outstanding option contracts that remain open and have not yet been closed, exercised, or expired.
Unlike volume, which resets every trading day, open interest accumulates over time and provides valuable insight into market participation.
A rising Open Interest generally indicates that new positions are being created, while declining Open Interest suggests that traders are closing existing positions.
Many traders use changes in Open Interest together with price movement to estimate market sentiment.
For example, increasing prices accompanied by rising Open Interest often indicate fresh buying activity and strengthening bullish sentiment.
Conversely, falling prices with increasing Open Interest may suggest strengthening bearish sentiment.
Although Open Interest alone does not predict future market direction, it provides useful information when analysed alongside price action and trading volume.
Another important field displayed in modern option chains is **Implied Volatility (IV)**.
Implied Volatility reflects the market's expectation of future price fluctuations and plays a major role in determining option premiums.
Higher implied volatility generally leads to higher option premiums because larger expected price movements increase the probability that options may become profitable before expiration.
Lower implied volatility usually results in lower premiums because expected market movement is relatively limited.
Many professional traders analyse implied volatility before selecting option strategies.
For example, premium buyers often prefer relatively low implied volatility because option prices are comparatively cheaper.
Premium sellers frequently prefer higher implied volatility because they receive larger premiums while expecting volatility to decline later.
The option chain also displays the **Change in Open Interest**, often abbreviated as **Change in OI**.
This field shows how much Open Interest has increased or decreased compared with the previous trading session.
A significant increase in Open Interest often indicates fresh participation by market participants, whereas a sharp decline may suggest profit booking or position unwinding.
Analysing Change in OI together with price movement helps traders better understand whether current market trends are supported by new positions or driven primarily by short-term trading activity.
Another useful feature available in many option chains is the identification of the **maximum Open Interest strike**.
Strikes with exceptionally high Call Open Interest are often viewed as potential resistance levels because many traders have sold call options there.
Similarly, strikes with very high Put Open Interest are frequently considered potential support levels because substantial put writing has taken place.
Although these levels do not guarantee future price behaviour, many traders use them as reference points while planning trades and identifying important market zones.
Reading an option chain effectively requires combining multiple pieces of information rather than relying on any single column.
For example, a trader analysing a particular strike price may simultaneously consider its premium, trading volume, Open Interest, implied volatility, bid-ask spread, and distance from the current market price before deciding whether to initiate a position.
This comprehensive approach leads to more informed decision-making than focusing solely on option premiums.
As traders gain experience, the option chain gradually becomes one of their most valuable analytical tools. Instead of viewing it as a table filled with numbers, they begin recognizing patterns that reveal market sentiment, liquidity, volatility expectations, and potential support or resistance levels.
Mastering the option chain is therefore an essential step in becoming a successful options trader. It provides the information needed to select appropriate strike prices, evaluate trading opportunities, understand market participation, and apply option strategies with greater confidence. Every advanced options strategy introduced later in this module relies on the ability to interpret the option chain accurately, making this chapter one of the most practical and important foundations for effective options trading.