Background <p>The longstanding financing challenges in Nigeria’s health sector which have resulted in undesired health outcomes, have necessitated the investigation of factors responsible for the apparent gap in fiscal prioritization. An earlier study shows that there is low citizen influence on healthcare financing in Nigeria, thus impacting gaps persist regarding the scale and drivers of citizen participation.</p> Method <p>This study utilized a modified two-sided stakeholder model to assess citizen engagement in primary healthcare financing. A survey was conducted among 400 citizens and civil society organizations (CSOs) to gauge experiences, perceptions, priorities, and participation levels in advocating for enhanced primary healthcare financing.</p> Result <p>Descriptive analysis uncovered significant challenges faced by Nigerians in accessing basic healthcare, with a strong collective desire for universal health coverage. Healthcare emerged as a pivotal consideration in evaluating political leaders, although it is not universally viewed as the government's primary concern. Chi-square tests revealed correlations between age groups and participation levels, as well as preferred information sources. Notably, findings suggest limited awareness and involvement in health policymaking, particularly among youth, possibly linked to insufficient coordination between CSOs and the public.</p> Conclusions <p>The study underscores critical gaps in citizen engagement within primary healthcare financing in Nigeria. Despite widespread desire for improved healthcare access and coverage, actual participation and awareness levels remain suboptimal. Addressing this requires enhanced coordination and communication strategies between CSOs and the public to amplify citizen influence on health policymaking and implementation.</p>