The aim of this paper is to identify how the mobility between different types of broadly defined occupation (hired work, self-employment in industry, services and agriculture or social security beneficiaries) changes personal income of individuals. We apply the Markov matrices to the panel data on 30,540 individuals for 2007-2008 from the Polish Household Budget Surveys. Our hypothesis is that a change of occupation affects individual capability to earn income, controlling for the occupation a person quits and the occupation a person starts, as well as age, education level and a permanent or temporary character of work. We test our hypothesis using the regression analysis. Our results show that the inter-occupational mobility matters mostly for those quitting hired work for self-employment, for the better educated, as well as for respondents above 60 years of age.