Background: Patient requests for tests, treatments, or referrals occur frequently during primary care visits and pose challenges for clinicians to address, but little is known about patient characteristics that may predict requests. Objective: To identify patient characteristics associated with a higher rate of patient requests during primary care visits. Design, Setting, and Sample: Cross-sectional analyses of data from 1141 adult patients attending 1319 visits with 56 primary care physicians (including 45 resident and 11 faculty physicians) in an academic family medicine practice. Measurements: Postvisit patient surveys including measures of patient requests for tests, prescriptions, and referrals; sociodemographics; mental and physical health status; symptom bother or worry (3-item scale; range, 3 to 15; Cronbach's alpha = 0.83); global life satisfaction; medical skepticism; and Five Factor Model personality traits. Results: Patients made 1 or more requests in 867 visits (65.7%). In multivariate analyses of the within-visit request count, the following patient variables were statistically significantly associated with a higher rate of requests: age in years (incidence rate ratio [IRR], 1.01 [95% CI, 1.00 to 1.01]), increased symptom bother or worry (IRR, 1.06 [95% CI, 1.03 to 1.08]), a more extroverted personality (IRR, 1.12 [95% CI, 1.03 to 1.08]), greater life satisfaction (IRR, 1.01 [95% CI, 1.00 to 1.02]), and any prior encounter with the visit physician (IRR, 1.17 [95% CI, 1.04 to 1.32]). Conclusions: Primary care physicians should expect a greater frequency of requests from older patients, patients with greater symptoms bother or worry, more extroverted patients, patients with greater global life satisfaction, and patients with whom they have had prior visits.