Women’s political participation remains persistently low in Nigeria despite constitutional guarantees of equality and multiple policy commitments to gender inclusion. This study examines the influence of socio-cultural and religious norms on women’s political participation, drawing evidence from the Nigerian National Assembly. Adopting a mixed-methods research design, the study combines quantitative data from 35 structured questionnaires administered to National Assembly staff with qualitative insights from 3 in-depth interviews and two focus group discussions. Quantitative data were analysed using descriptive statistics and Spearman correlation, while qualitative data were subjected to thematic analysis. The findings reveal that cultural and religious norms constitute significant informal barriers to women’s political participation. Female respondents perceived these barriers more strongly than their male counterparts, reflecting gendered lived experiences within political institutions. Although higher educational attainment was associated with reduced perception of normative constraints, socio-cultural and religious expectations continued to dampen women’s political ambition and perceived participation. Qualitative evidence further demonstrates that patriarchal values, traditional gender roles, and religious interpretations reinforce perceptions of politics as a male domain, subjecting women to heightened moral scrutiny and social resistance. The study concludes that formal political reforms alone are insufficient to improve women’s representation unless accompanied by deliberate efforts to transform underlying socio-cultural and religious norms. Targeted normative change interventions are therefore essential for advancing gender-inclusive political participation.