Does the status of certain temporal experiences as illusory depend on one's conception of time? Our concept of time in part determines our concept of what we hold to be real and unreal; what we hold to be real and unreal partially determines what we hold to be illusory; thus, our concept of time in part determines what we hold to be illusory.This paper argues that this dependency of illusions on the concept of time is applicable to illusions of time. Two possible temporal illusions given the evidence are examined, simultaneity and the experience of the past; it is argued that the evidence points at temporal illusions depending on which conception of time is true.