Ministerial cabinets hold a central place in the Belgian politico-administrative system, carrying out the bulk of policy formulation. However, they do not operate in isolation and rely on other actors of the policy advisory system for information supply and advice. They request and receive advisory inputs from these actors and use them to formulate policy proposals. This article investigates how ministerial advisers utilize policy advice when they formulate policies. Based on a survey targeting ministerial cabinet members, it shows that policy advice utilization varies according to the source and its location in the policy advisory system. The sample consists of ministerial advisers from eleven ministerial cabinets, from the two Belgian federated entities’ governments of Wallonia and the Wallonia-Brussels Federation. Ministerial advisers still predominantly use advice from civil servants, which points to the continued importance of advice provision from internal, in-house sources. However, advice from external actors, such as trade unions, civil society, or consulting firms have been observed to have a rather high incidence on policy formulation activities too. Advisory bodies appear to be very much active in supplying advice, but this same advice does not yield comparatively higher utilization scores.