IntroductionA key element of the global drive to universal health coverage is ensuring access to needed health services for everyone, and to pursue this goal in an equitable way. This requires concerted efforts to reduce disparities in access through understanding and acting on barriers facing communities with the lowest utilisation levels. Financial barriers dominate the empirical literature on health service access. Unless the full range of access barriers are investigated, efforts to promote equitable access to health care are unlikely to succeed. This paper therefore focuses on exploring the nature and extent of non-financial access barriers.MethodsWe draw upon two structured literature reviews on barriers to access and utilization of maternal, newborn and child health services in Ghana, Bangladesh, Vietnam and Rwanda. One review analyses access barriers identified in published literature using qualitative research methods; the other in published literature using quantitative analysis of household survey data. We then synthesised the key qualitative and quantitative findings through a conjoint iterative analysis.ResultsFive dominant themes on non-financial access barriers were identified: ethnicity; religion; physical accessibility; decision-making, gender and autonomy; and knowledge, information and education. The analysis highlighted that non-financial factors pose considerable barriers to access, many of which relate to the acceptability dimension of access and are challenging to address. Another key finding is that quantitative research methods, while yielding important findings, are inadequate for understanding non-financial access barriers in sufficient detail to develop effective responses. Qualitative research is critical in filling this gap. The analysis also indicates that the nature of non-financial access barriers vary considerably, not only between countries but also between different communities within individual countries.ConclusionsTo adequately understand access barriers as a basis for developing effective strategies to address them, mixed-methods approaches are required. From an equity perspective, communities with the lowest utilisation levels should be prioritised and the access barriers specific to that community identified. It is, therefore, critical to develop approaches that can be used at the district level to diagnose and act upon access barriers if we are to pursue an equitable path to universal health coverage.Electronic supplementary materialThe online version of this article (doi:10.1186/s12939-015-0181-z) contains supplementary material, which is available to authorized users.