Telephone medicine is often preferred by patients to meet primary care needs and may be associated with high patient satisfaction. This article presents findings about incoming patient calls to primary care for medically based reasons during office hours and reports factors independently associated with telephone encounter satisfaction, considering patient characteristics, call reasons, and staff responsiveness, for a national cohort of primary care users. Interviews were conducted with patients from 18 nationwide primary care clinics during the fall of 2009. Calling for an urgent medical issue was associated with dissatisfaction. Odds of call satisfaction were greater when patients thought staff was friendly (10×), call answer was timely (5×), and needed medical information was provided (7×). These findings can be used for interventions to optimize telephone access and patient satisfaction which is beneficial because satisfactory telephone encounters reduce primary care use and satisfied patients are more likely to be engaged in their health care.