Academic startups have a considerable economic impact, which is why public support programmes for them are considered an important component of innovation and technology policy. In this context, university support programmes can be an important part of the policy toolkit by aiming to improve universities’ startup environment and thus promote startup activity at those institutions. Assessing the effectiveness of these programmes is a key evaluation task inasmuch as it provides an evidence base for decision-makers and broadens the discourse on promoting startup culture at universities. This study reports on the background, methodology, and results of the evaluation of the effectiveness of a large university support programme in the academic startup sector in Germany, ‘EXIST—Leverage of potentials’. This programme supports universities which have little experience in building a startup culture and startup-supportive structures. Reliable data are available for two indicators that can be employed to assess intervention effects by means of a difference-in-differences design, namely for the number of applications universities submitted and the number of grants they received in what is Germany’s largest funding programme for prospective startups. The findings indicate that funding by ‘EXIST—Leverage of potentials’ positively affects universities’ activities in the area of startup support.