Introduction: The role of primary care in the United States is vitally important to improving health outcomes, minimizing waste, and controlling cost. The Military Health System is tasked with both caring for its beneficiaries and ensuring the medical readiness of active duty service members, who often have needs unique to those in the civilian population. Balancing the number of individuals assigned to a primary care clinician with the clinician's capacity to meet their medical needs and anticipated appointment demand is a fundamental cornerstone of effective primary care clinic management in any setting. Materials and methods: Using the Military Health System Data Repository, this cross-sectional study utilized descriptive statistics and Poisson regression to describe crude and adjusted primary care appointment utilization trends among Military Health System beneficiaries during fiscal year 2016. Results: The primary care appointment utilization rate of the study population was 3.3 visits per person-year. The youngest and oldest age groups, women, active duty, and those enrolled to Army clinics had the highest utilization rates within each of the respective covariates. Active duty women had the highest utilization of any group in the data set, with a crude rate of 4.7 visits per person-year. Conclusions: Primary care utilization trends are different among different demographic subgroups within the Military Health System (MHS). Unmet demand, patient acuity, clinician continuity, robustness of team support, and other important factors that influence appointment utilization were not incorporated in this study. Superficially, these data suggest that the MHS enrollment target of 1,100-1,300 patients per full-time primary care clinician is roughly appropriate, though this should be interpreted with caution given the limitations.