Call Option
A call option grants the buyer the right to acquire the underlying asset at the strike price on or before expiry, while the seller is obligated to deliver if the buyer exercises. Call options on Nifty 50 and individual F&O stocks are actively traded on NSE.
The buyer of a call option profits when the underlying asset rises above the strike price by more than the premium paid. For example, if a participant purchased a Nifty 18,000 call option for ₹100 and Nifty settled at 18,200 on expiry, the intrinsic value at expiry was ₹200, yielding a profit of ₹100 per unit after recovering the premium.
Call option writers (sellers) collect the premium upfront and retain it as profit if the underlying closes below the strike at expiry. The risk for an uncovered call writer is theoretically unlimited because there is no upper bound on how high the underlying can move. Covered call writing — where the seller already holds the underlying stock or index equivalent — limits this directional risk and is one of the most commonly discussed income-generating strategies in options.
On NSE, call options across various strikes and expiries are available simultaneously. The most liquid strikes tend to cluster near the at-the-money level, where trading interest from both hedgers and speculators is highest. Deep in-the-money calls behave similarly to the underlying itself, with a delta close to 1, while deep out-of-the-money calls are predominantly driven by time value and implied volatility.
A widely held misconception is that rising markets automatically make call options profitable. In practice, if implied volatility contracts sharply even as the underlying rises — a scenario observed historically during gradual up-trending markets — call option buyers have found their positions losing value despite a favourable directional move. This effect, where falling IV erodes the time value component faster than intrinsic value accumulates, is sometimes called a volatility crush.
Call options play a structural role in strategies such as covered calls, bull call spreads, and call ratio back spreads. Each of these structures has a distinct risk-reward profile and responds differently to changes in underlying price, time, and volatility. No single strategy is universally superior; suitability depends on the participant's risk tolerance, market view, and available capital.