Nudging is considered a promising approach for behavioural change. At the same time, nudging has raised ethical concerns, specifically in relation to the impact of nudges on autonomous choice. A complexity is that in this debate authors may appeal to different understandings or dimensions of autonomy. Clarifying the different conceptualisations of autonomy in ethical debates around nudging would help to advance our understanding of the ethics of nudging. A literature review of these considerations was conducted in order to identify and differentiate between the conceptualisations of autonomy. In 33 articles on the ethics of nudging, we identified 280 autonomy considerations, which we labelled with 790 unique autonomy codes and grouped under 61 unique super-codes. Finally, we formulated three general conceptualisations of autonomy. Freedom of choice refers to the availability of options and the environment in which individuals have to make choices. Agency involves an individual's capacity to deliberate and determine what to choose. Self-constitution relates to someone's identity and self-chosen goals. In the debate about the ethics of nudging, authors refer to different senses of autonomy. Clarifying these conceptualisations contributes to a better understanding of how nudges can undermine or, on the other hand, strengthen autonomy.