This research aims to analyze individual and national level factors that influence opportunity-driven senior entrepreneurship (people older than 65 years) in a group of 12 OECD countries. At this age most people in developed economies could choose between retiring, continuing working, or starting a new venture. It is important to understand the motivations behind their decision. We use data from the Global Entrepreneurship Monitor (GEM), to identify the effect of attitudes, perceptions, and aspirations as well as their sociodemographic characteristics. The sample consists of 24,139 observations from individuals older than 65 years. Additionally, we used the Human Development Index (HDI) – from the United Nations database–, to measure the country's level of development. Because of the nested nature of the data, we estimate our models using a multilevel logistic regression. Our results show that income, education, and occupation, in conjunction with the level of human development of a country have a significant influence on the probability of entrepreneurship by opportunity for senior individuals (+ 65). This research has policy and practical implications related to the decision of senior people to explore the creation of a new venture instead of opting for other alternatives such as retiring.