The notion that parties organise as stratarchies in which power is divided between different levels of organisation a popular one (Carty 2004; Bolleyer 2011). It is even one of the key elements of Katz and Mair’s (1995) cartel party model. Using data from the Political Parties database, which includes data about the organisation of political parties in 19 countries, this paper will analyse the multilevel organisation of statewide political parties along two dimensions (autonomy/self-rule of regional parties, and shared rule/influence of lower party levels in the central party). It will then assess whether parties are organised stratarchically as a response to institutional incentives (to match the structure of the state) or because they are fully-fledged carte parties.