The article examines the definitions of time in Sāṃkhya from the first commentaries on the Sāṃkhyakārikās up to Vijñānabhikṣu’s works. These texts all deny the existence of time as an entity existing over and above the three constitutive elements of reality acknowledged in the tradition (i.e. the Person, Nature, and its manifest evolutes); but they have strikingly different ways of justifying this denial. The Yuktidīpikā offers by far the most elaborate definition; it argues that time cannot be an eternal, omnipresent and static substance as the Vaiśeṣikas contend, and is but a relative concept that results from our comparing various actions – an idea probably inspired by grammatical and astronomical sources. The article outlines the reception of the argument by its Vaiśeṣika adversaries and its fate within Sāṃkhya. It seeks to explain how the commentaries on the late Sāṃkhyasūtras, while still defending the principle that time is no distinct entity, ended up presenting time as being exactly what the Yuktidīpikā’s author had staunchly refused to admit: an eternal, static and omnipresent substance. It shows how this new understanding of time in Sāṃkhya was projected by late exegetes onto a twelfth-century Vaiśeṣika manual by Śivāditya, which has led modern historians to misunderstand Śivāditya’s definition of time. It also highlights differences between the Sāṃkhya and Pātañjalayoga views on time – notably the assertion in the Yogabhāṣya that contrary to succession, the moment (kṣaṇa) is real – and the ways in which commentators reacted to these apparent discrepancies, by ignoring them (as Vācaspatimiśra), by attempting to conciliate the Yogabhāṣya with the Yuktidīpikā’s argument (as the Yogavivaraṇa’s author) or by underscoring the incompatibility of the Sāṃkhya and Yoga views on time (as Vijñānabhikṣu). Accessible at https://paris3.academia.edu/IsabelleRati%C3%A9