Immigrant women are less likely to be screened for cervical cancer in Ontario. Religion may play a role for some women. In this population-based retrospective cohort study, we used country of birth as a proxy for religious affiliation and examined screening uptake among foreign-born women from Muslim-majority versus other countries, stratified by region of origin. We linked provincial databases and identified all women eligible for cervical cancer screening between April 1, 2012, and March 31, 2015. Women were classified into regions based on country of birth. Countries were classified as Muslim-majority or not. Being born in a Muslim-majority country was significantly associated with lower likelihood of being up-to-date on Pap testing, after adjustment for region of origin, neighborhood income, and primary care-related factors [adjusted relative risk (ARR), 0.93; 95% (confidence interval) CI, 0.92-0.93]. Sub-Saharan African women from Muslim-majority countries had the highest prevalence of being overdue (59.6%), and the lowest ARR for screening when compared with women from non-Muslim-majority Sub-Saharan African countries (ARR, 0.77; 95% CI, 0.76-0.79). ARRs were lowest for women with no primary care versus those in a capitation-based model (ARR, 0.28; 95% CI, 0.27-0.29 overall). We have shown that being born in a Muslim-majority country is associated with a decreased likelihood of being up-to-date on cervical screening in Ontario and that access to primary care has a sizeable impact on screening uptake. Screening efforts need to take into account the background characteristics of population subgroups and to focus on increasing primary care access for all. .