Purpose Drawing on a unique combination of longitudinal administrative data and a postal survey, the purpose of this paper is to identify the socio-economic factors and individual characteristics that affect senior citizens’ decision to continue working on the Swedish labour market after the standard retirement age. Design/methodology/approach By using standard econometric techniques (multinomial logit model) on a large representative sample of 20,000 senior citizens residing in Sweden, the auhtors analyse the extent to which socio-economic factors and individual characteristics including personality traits affect the decision of senior citizens to delay retirement and to continue working after the standard retirement age. Findings The results of our estimations show clearly that good health, high educational attainment/high-skilled jobs, good psychosocial work environment, employment status (to be self-employed), personality traits (extraversion, openness to experience and conscientiousness) as well as industrial sectors (agriculture, healthcare and transport) are strong predictors of the continuation of work after the standard retirement age (65 years old). Research limitations/implications High job quality and good working conditions, along with continuous improvements in public health, are seemingly essential elements for motivating senior workers to delay retirement as are preventive policy measures favouring the development of decent and sustainable working conditions across the life course. Originality/value To the best of the authors’ knowledge, the paper is the first attempt in Sweden to analyse jointly a large range of factors influencing the decision to remain in the labour force after the standard/normal pension age, including psychosocial working conditions and personality traits.