Understanding how policy design and implementation differ under populist and non-populist governments is complicated by the fact that populism never exists in a pure form and is always attached to a more developed ideology. Leveraging the near-simultaneous election of left-wing populist Andrés Manuel López Obrador in Mexico and right-wing populist Jair Bolsonaro in Brazil, this article analyses populism’s effect on cash transfer programmes. Despite the diametrically opposed ideologies of their presidents, rather than diverging, Mexican and Brazilian cash transfer policies converged under populism. Both leaders rebranded the programmes they inherited and moved policy in an improvised, politicised and clientelistic direction.