Cooperatives play a critical role in their members’ adaptation to climate change. Yet, we know little about the conditions under which they support their members to adapt, especially in the agricultural sector of the Global South. Hence, we assess the impact of membership in cooperatives and of the access to their services (specifically extension, credit, and market services) on members’ adaptation to climate change. We empirically test the impact of membership in cooperatives and access to their services using survey data from 792 small potato farms from rural Kenya that differ in their adoption of climate-smart practices. We employ propensity score matching estimation with conditional analysis to causally relate adoption of climate-smart practices to membership and access to specific services. Findings first confirm that cooperatives have a positive impact on their members’ climate change adaptation. Second, we show that access to market and credit services is particularly critical for climate change adaptation. Third, while access to the cooperative’s extension is per se less impactful, this service strengthens the impact of market and credit services.