The main objective of this paper is to analyze the effect of education, age, access to ICTs and physical and financial assets, as well as other personal and socioeconomic characteristics, on the probability of being self-employed, formal and informal. For the achievement of this purpose, information will be used at the urban level for the 21 main cities in Colombia, the Great Integrated Household Survey –GEIH–, the National Administrative Department of Statistics –DANE–, for the year 2010, and the Colombian Longitudinal Survey of the Universidad de los Andes –ELCA–, for the year 2013, applying the models that have a qualitative binomial and multinomial dependent variable, correcting the selection bias. As main results, it was found that physical assets and access to credit have a positive marginal effect on the probability of being self-employed. On the other hand, the marginal effect of education was negative, at a lower educational level, the greater the probability of self-employment, especially the informal one. The version here presented corresponds to the updated study.