The French term ‘cohabitation’ is commonly used to describe situations in semi-presidential systems where the prime minister and the president represent different political parties. The present contribution sets out to test to what extent cohabitation affects the powers of the president both in dual executives with popularly elected presidents and in systems with indirectly elected presidents. The purpose is also to assess to what extent the relationship between cohabitation and presidential powers is affected by whether cohabitation is broadly or narrowly defined. Empirically, the study is extensive in time and space. The research population consists of all democratic republics with a separate president and prime minister during the time period 1850–2022. The results show that presidential powers are reduced in times of cohabitation, but this relationship is detected primarily in semi-presidential systems with popularly elected presidents and when cohabitation is broadly defined.