Party mandate theory claims that parties form government coalitions so that they can fulfil their election promises. This article looks at the party mandate model as applied to the arena of post-communist Europe and at the obstacles that can prevent a party from fulfilling its mandate (the presence of a new type of party, hyperaccountability, short-lived governments). The article describes the findings from a study examining the degree to which socio-economic legislative promises were fulfilled by the second government of Mirek Topolánek, the first government of Petr Nečas, and the (recent) government of Bohuslav Sobotka after a year and a half for all governments, and in the end of the term for Topolánek’s and Nečas’ governments. Coalition parties were found to have fulfilled 19–40% of their election promises after a year and a half in office, and this percentage had only increased slightly by the time the two governments that were studied for the full duration of their time in office had reached the end of their term. Binary logistic regression models revealed that the odds of election promises being fulfilled are greater if a promise is formulated as a commitment to maintain the status quo and if a promise is consensual and included in a coalition agreement. By contrast, there was no effect observed to result from party control of government ministries or from the advantage of being the prime ministerial party.