Why Does a Long Put Option Have a Negative Delta?

A long put option gives the holder the right to sell the underlying asset at the strike price. Since the value of this right increases as the underlying asset's price falls, and decreases as the underlying price rises, the put option's price moves inversely to the underlying price.

This inverse relationship is mathematically represented by a negative Delta, ranging from -1 (deep ITM) to 0 (deep OTM).

Why Does the Required Hedge Size Change as the Underlying Asset’s Price Moves?
How Does Time Value Decay Accelerate as an Option Moves from ATM to Deep ITM?
What Is ‘Time Decay’ or ‘Theta’ in Options?
How Does an Option’s Extrinsic Value Change as It Moves from OTM to ITM?
How Does an Option’s Delta Change as Its Expiration Date Approaches?
What Is the Delta of a Short Call Option Position?
How Does a Decrease in the Underlying Price Affect the Delta of an OTM Call?
How Does the Delta of an Option Change as It Moves Deeper into the Money?

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