There is widespread and growing interest in designing and implementing social health insurance schemes (SHIS) across many low- and middle-income countries as a means to improve financial protection and achieve universal health coverage. SHIS recently gained traction in Nigeria, but evidence regarding optimal design features of SHIS is sparse and there is lack of a simple and standardised checklist that scheme designers, implementers and researchers could use to assess, guide and inform the design of SHIS. This paper seeks to develop a checklist based on concepts as well as theoretical and empirical evidence that can inform and guide scheme designers and implementers on design options to maximise the effectiveness of the scheme.We conducted a review of literature exploring the relevant concepts for the development of a framework and checklist to identify the key factors or variables required to inform the design of SHIS. The checklist details critical considerations/questions to address and options for design. The developed checklist was then used to examine conditions for readiness and appropriateness of SHIS design in two states in Nigeria (Kaduna and Niger).This paper describes the development of a SHIS checklist. The findings also demonstrate that the newly developed checklist, consisting of six design domains, can be used by scheme designers and policy-makers as a simple and effective tool to assess and inform SHIS design features across Nigeria to maximise the chances of the effectiveness of the schemes.In conclusion, given that the development of SHIS in the Nigerian states is still in its early stages, applying the SHIS design checklist can serve as a first step to ensuring a feasible and sustainable insurance scheme. The introduction of SHIS, if properly designed and implemented, can be a significant first step towards improving the accessibility, equity and efficiency of healthcare in Nigeria.