Why Options With the Same Strike Have Different Prices Across Expirations

A 100-strike call expiring in 14 days and a 100-strike call expiring in 60 days are different option series.

They share a strike, but not the same remaining time, expiration event set, Greek profile, or implied-volatility horizon.

How to choose an option expiration explains how those differences affect contract selection.

Before expiration, option premium can contain intrinsic value and time value.

All else equal, more remaining time gives the underlying more opportunity to move, so a longer-dated option often carries more time value.

OIC notes that longer remaining life generally supports more time value, while time value falls toward zero by expiration.

Intrinsic value and time value explains how to separate those components.

Short-dated at-the-money options usually have faster time decay and higher gamma concentration.

Longer-dated options usually carry more vega, so changes in implied volatility can have a larger dollar effect.

That means two options with the same strike can respond differently to the same one-day stock move or volatility change.

Different expirations do not have to use the same implied volatility.

An earnings report, macro event, stress episode, or supply-demand imbalance can raise IV in one expiration more than another.

Implied volatility term structure explains why a shorter option can sometimes look unusually expensive relative to a later one.

Rates and expected dividends can also affect option values differently across horizons.

Assume the stock is 100 and both calls use a 100 strike.

Suppose the 14-day call is 2.20 and the 60-day call is 5.40. With a 100-share multiplier, the cash premiums are 220 and 540 before fees.

The longer contract costs 320 more in this example: 540 - 220 = 320.

If hypothetical theta is -0.12 for the 14-day call and -0.06 for the 60-day call, one unchanged day would imply about 2.08 and 5.34 before other inputs move.

Those theta estimates are local model sensitivities, not guaranteed next-day prices.

- Use the same underlying, strike, option type, and quote timestamp - Record days to expiration for each contract - Compare bid, ask, IV, theta, gamma, and vega - Mark earnings, dividends, and other events inside each expiration - Check rates and settlement or exercise differences when relevant - Compare liquidity before treating a displayed premium as executable [!TRYMARK] Expiration-price checkpoint At the September 18 close, record both expirations, same strike, bid, ask, IV, theta, gamma, vega, event dates, and multiplier before explaining the premium difference.

A higher premium is not automatically better or worse. It reflects a different package of time and risk exposures.