The paper analyzes the factors influencing situation and retirement decisions of different cohorts in Poland in years 1995-2007. We checked if changes in economic activity at the later stage of professional life can be observed via changes in the social security legislation and their consequences for different cohorts. Separate pseudo-panel models were estimated for men and women based on the annual Household Budget Survey datasets. The results show that apart from variables usually identified in the literature that have a significant impact on retirement decisions, institutional changes are also significant in case of Poland. Especially regulations concerning access to pre-retirement allowances and benefits turned out to be significant, as well as changes in possibility to combine work and receiving pension.