Why Do Options with the Same Strike Price but Different Expiration Dates Have Different Premiums?

Options with the same strike price but different expiration dates have different premiums primarily due to the difference in their extrinsic (time) value. The option with the longer time to expiration will have a higher extrinsic value because there is more time for the underlying asset's price to move favorably, increasing the probability of a profitable outcome.

All else being equal, the longer-dated option will always be more expensive than the shorter-dated option.

What Is the Difference between Intrinsic Value and Extrinsic Value of an Option?
Why Are Longer-Dated Options Typically More Expensive than Short-Dated Options for the Same Strike?
What Is Another Common Name for the Extrinsic Value of an Option?
What Is the Concept of “Extrinsic Value” and How Does It Relate to ITM Options?
How Does the Time Remaining until Expiration Affect the Option’s Time Value?
How Does the “Moneyness” of an Option Affect Its Premium Value?
How Does the Premium Relate to the Intrinsic and Extrinsic Value of an Option?
How Does the Strike Price Affect the Option Premium?

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