This study evaluated the effects of community engagement through social accountability on service users’ values, attitudes and interactions. We conducted a pre–post study of the community and provider driven social accountability intervention (CaPSAI) over a 12-month period among 1,500 service users in 8 health facilites in Ghana and in Tanzania (n = 3,000).In both countries, there were significant improvements in women’s participation in household decision-making and in how service users’ perceive their treatment by health workers. In both settings, however, there was a decline in women’s knowledge of rights, perception of service quality, awareness of accountability mechanisms and collective efficacy in the community. Though CaPSAI intervention set out to change the values, attitudes, and interactions between community members and those providing contraceptive services, there were changes in different directions that require closer examination.