Background: Oral diseases remain a major public health concern in Ife North, Osun State, Nigeria, and utilization of oral health services remains low, particularly within primary health care (PHC) settings. Despite integrating basic oral health care into PHC services, many Nigerians do not access available dental care. Objectives: This study assessed the level of oral health service utilization, socio-demographic determinants, knowledge, attitudes, and perceptions, and barriers to accessibility and affordability of oral health services among patients attending PHC facilities in Ife North, Osun State, Nigeria. Methods: We conducted a descriptive cross-sectional study among 168 patients attending selected PHC facilities in Ife North, Osun State, between [Month-Month, Year]. We selected participants using systematic random sampling. We collected data using a validated, pretested structured questionnaire and analyzed them with SPSS version 25.0. Descriptive statistics, chi-square tests, and logistic regression analyses were performed at a 5% significance level. Results: The mean age of respondents was 34.6 ± 10.2 years. Females accounted for 61.3% of participants, while 55.4% had secondary education. Only 38.7% had ever visited a dental clinic, and 21.4% (of those who had visited) reported regular utilization of oral health services. Major barriers included high treatment costs (73.2%), poor accessibility (64.9%), fear of dental procedures (58.9%), and low awareness of available oral health services (55.4%). In multivariable logistic regression, income >₦100,000/month (AOR = 4.82, 95% CI: 2.01-11.55, p < 0.001), tertiary education (AOR = 3.17, 95% CI: 1.42-7.09, p = 0.005), awareness of PHC oral health services (AOR = 2.94, 95% CI: 1.38-6.28, p = 0.005), and professional/civil-servant occupation (AOR = 2.45, 95% CI: 1.17-5.14, p = 0.018) were significant positive predictors, while fear of dental treatment (AOR = 0.41, 95% CI: 0.19-0.88, p = 0.022) and high treatment cost (AOR = 0.38, 95% CI: 0.17-0.84, p = 0.017) were significant negative predictors of utilisation. Conclusion: Oral health service utilization among PHC attendees in Ife North remains low, and the identified socio-demographic, financial, and attitudinal factors were associated with utilization rather than causally determining it. Strengthening health education, reducing financial barriers, improving accessibility, and increasing community awareness may enhance service uptake and oral health outcomes in similar PHC settings.