On 15 August 2022, Scotland made history as the first country to enact the universal provision of free menstrual products, in accordance with the Period Products (Scotland) Act 2021. This policy development challenges conventional assumptions found in comparative and gender welfare theories, which typically associate socially and gender-progressive legislation with universal welfare regimes rather than those, like the devolved UK, which adhere to more liberal and gender-blind welfare traditions. To understand how and why Scotland came to adopt such a progressive policy, this paper combines insights from policy design theory and Feminist Institutionalism to analyse the policy’s design process. In particular, it unpicks the gendered logics and norms which influenced the perceived desirability and feasibility of universal free provision in a context of strong political pressure to instead adopt measures specifically targeted to individuals in education or experiencing poverty. Drawing on a range of documentary and interview data, the paper shows how ideas concerning poverty, equity, social justice, and gender were actively (re)configured by a range of political and civil society actors to advocate for a universal rather than a targeted policy. In doing so, the paper highlights how historically entrenched feminist ideals and institutionalised norms of partnership working among feminists inside and outside the state allowed these actors to successfully advance progressive feminist ideals despite strong initial political resistance to a universal policy’s costs and feasibility.