This article uses single mothers’ pursuit of child support (child maintenance) to examine how the state governs gender through post-separation financial responsibilities. We draw on interview data to detail how the Australian welfare state compels single mothers’ child support provisioning through claims work and the associated strategies of managing information, emotions and government workers. Despite their sustained efforts, provisioning afforded single mothers’ limited financial benefits. We argue that this outcome reflected a gendered policy and implementation regime that normalised masculine financial discretion and simultaneously compelled single mothers’ provisioning and failed to accord it legitimacy. Provisioning did, however, benefit the welfare state, which appropriated single mothers’ time and knowledge to claim and perform key functions. We conclude that the necessity and challenges of child support provisioning were not indicative of a failing child support programme but rather reflected its role in the reproduction of gendered power, responsibilities and rewards in post-separation parenting.