The state reform was elaborated at a moment when large fiscal consolidation measures were required to restore the long-term sustainability of Belgian public finances. The 2011 institutional agreement provided that the federated entities contribute, through the reform, to the fiscal consolidation. That contribution can be justified by the fact that the reform, by reducing the budgetary size of the federal level, decreases the federal level’s room for manoeuvre and its capacity to resolve on its own the sustainability issue. The magnitude of the contribution necessary to prevent the sustainability challenge from deteriorating is assessed and compared to the redistribution of the public deficit as organized by the reform. The assessment is made in a constant policy scenario and for different assumptions about the reform's life span. This study shows that the transfer of fiscal burden to the federated entities is, a priori, sufficient not to aggravate the sustainability problem considering the reduced size of the federal level’s budget. The federated entities have gained scale and powers but will have to contribute substantially to the efforts to restore fiscal sustainability.