This article provides a preliminary assessment of the impact of the Brexit process—from the June 2016 referendum to June 2018—on the British political system. Drawing on the classic work of Arend Lijphart and the ensuing scholarship applying the Westminster model to Britain, it seeks to understand whether and to what extent Brexit has impacted on the majoritarian features of the system. Adapting Lijphart's criteria, it focuses on the electoral‐party dimension, the executive–legislative relations and the territorial power‐sharing arrangements. It argues that Brexit has brought to light several intertwined tensions that had been brewing inside British politics over the course of a number of years, and which are likely to continue unfolding for several years to come. Even if emerging trends tend to be fragile, complex, even contradictory, and the current uncertainty makes any long(er)‐term assessment futile, recent developments appear to signal a possible strengthening of the executive over the legislature and of the central over the devolved administrations, thus consolidating the majoritarian traits of the British political system.