The European Commission has been a trendsetter in requirements for open access to scientific peer-reviewed publications and for open research data / research data management. This article analyses the provisions and requirements as far as they regard repositories in the EU’s Horizon 2020 and the Horizon Europe research funding programmes. Repositories are a cornerstone of the open access and open data / data management requirements in both programmes, with a strengthening of these requirements in Horizon Europe. This will influence researchers and research manager requirements for repositories, even beyond the Horizon programmes. The new requirements have the potential to significantly contribute to the transition towards open science if they are stringently implemented.