Background: Childhood immunization is one of the most effective public health interventions for preventing vaccine-preventable diseases and reducing childhood morbidity and mortality. Despite the availability of national immunization programs, incomplete vaccination coverage remains a challenge in many low- and middle-income countries due to socioeconomic, educational, and healthcare-related barriers.Objective: To determine the vaccination coverage among children and identify factors influencing complete immunization in a tertiary healthcare setting.Methods: A retrospective observational study was conducted among 350 children aged 12–59 months attending pediatric outpatient and immunization clinics. Data regarding demographic characteristics, vaccination status, parental education, socioeconomic status, place of residence, birth order, and healthcare access were collected from immunization records and hospital databases. Vaccination status was classified as fully immunized, partially immunized, or unimmunized according to the National Immunization Schedule.Results: Of the 350 children included, 278 (79.4%) were fully immunized, 58 (16.6%) were partially immunized, and 14 (4.0%) were unimmunized. Higher maternal education, institutional delivery, regular antenatal care, urban residence, and higher socioeconomic status were significantly associated with complete immunization. The most common reasons for incomplete vaccination were lack of awareness (38.2%), missed appointments (25.0%), fear of adverse effects (18.4%), and limited healthcare access (18.4%).Conclusion: Although childhood vaccination coverage was relatively high, gaps in complete immunization persist. Maternal education, healthcare accessibility, and awareness play significant roles in improving vaccination uptake. Strengthening community education, reminder systems, and outreach services can further enhance childhood immunization coverage.