The study deals with strategies for legitimising non-participation in adult education and training (AET) in groups of people with the lowest levels of participation: low-educated workers, retired individuals and people on parental leave. It aims to identify and describe strategies for legitimising non-participation. Results are based on extensive qualitative research focused on mapping the situational determinants of non-participation in AET. For this purpose, a total of 53 semi-structured interviews were conducted and analysed. Through generic coding procedure, four key strategies were identified: (1) commitment to lifelong learning; (2) preference of experience over theoretical knowledge; (3) preference of complete dedication and (4) mobilisation of past educational experience. Each group of adults has a distinct way of using the strategies to justify their non-participation. The findings contribute to our knowledge of situational rationality that is used in decision-making regarding participation in AET.