IMPORTANCE: Telemedicine visits can offer patients convenient access to a clinician, but it is unclear whether treatment differs from that with in-person visits or how often patients require in-person follow-up. OBJECTIVE: To examine whether physician prescribing and orders differ between telemedicine and office visits, whether physicians conducting telemedicine visits are more likely to require in-person follow-up, and whether telemedicine visits are associated with more health events. DESIGN, SETTING, AND PARTICIPANTS: This cohort study included all patients who scheduled primary care appointments through the patient portal of a large integrated health care delivery system newly implementing patient-scheduled video telemedicine visits from January 2016 to May 2018. MAIN OUTCOMES AND MEASURES: Adjusted rates of any medication prescribed or laboratory tests or imaging ordered and rates of follow-up health care utilization (in-person visits, emergency department visits, and hospitalizations) within 7 days after the index visit, stratified by index primary care visit type, were generated using multivariable adjustment for patient, access, and clinical characteristics. RESULTS: This study included 1 131 722 patients (611 821 [54%] female; mean [SD] age, 43 [22] years) with 2 178 440 total appointments (307 888 [14%] telemedicine), of which 13.5% were for patients younger than 18 years, 22.2% were for patients 65 years or older, and 54.9% were for female patients. After adjustment, 38.6% (95% CI, 38.0%-39.3%) of video visits, 34.7% (95% CI, 34.5%-34.9%) of telephone visits, and 51.9% (95% CI, 51.8%-52.0%) of office visits had any medication prescribed; laboratory tests or imaging were ordered for 29.2% (95% CI, 28.5%-29.8%) of video visits, 27.3% (95% CI, 27.1%-27.5%) of telephone visits, and 59.3% (95% CI, 59.3%-59.4%) of clinic visits. After adjustment, follow-up visits within 7 days occurred after 25.4% (95% CI, 24.7%-26.0%) of video visits, 26.0% (95% CI, 25.9%-26.2%) of telephone visits, and 24.5% (95% CI, 24.5%-24.6%) of office visits. Adjusted emergency department visits and rates of hospitalizations were not statistically significantly different by primary care index visit type. CONCLUSIONS AND RELEVANCE: In this cohort study of patient self-scheduled primary care telemedicine visits within ongoing patient-physician relationships, prescribing and orders were significantly lower for telemedicine visits than for clinic visits, with slightly higher follow-up office visits for telemedicine but no difference in health events (emergency department visits or hospitalizations). Video or telephone visits may be a convenient and efficient way to access primary care and address patient needs.