This article considers the discussion and rejection of social insurance model of funding for the British National Health Service. Specifically it asks why the hospital contributory scheme movement had so little impact on policy debates in the 1940s. We argue that at the start of the policy-making process serious consideration was given to the incorporation of this mode of funding, not least because the contributory schemes, with some ten million members, played a major role in financing existing voluntary hospital provision. Early sections describe the growth and nature of the schemes, noting that, despite their large working-class constituency and the presence of labour movement representatives amongst their leadership, they remained peripheral to discussion of reform in the interwar period. We then trace the emergence of the proposal for an insurance-based 'hotel-charge' in civil servants' discussions about hospital funding the Beveridge Report. Officials, however, remained sceptical about the contributory schemes' capacity to deliver a comprehensive and efficient funding mechanism, given their lack of uniformity, the gaps in their coverage, and the limited progress of reciprocal arrangements between them. Finally, we note the ineffectiveness of the British Hospital Contributory Schemes Association as a player in the policy community. Its leadership had no clear strategy for influencing events and was reluctant to deploy pressure group tactics such as lobbying through the press or parliament. Crucially, the movement was divided internally between those members who supported the voluntary system and others who welcomed a publicly funded health service.