INTRODUCTION: Extended postpartum Medicaid has been implemented in some states to increase health care access, optimize maternal health, and reduce mortality. We sought to evaluate the effect of postpartum Medicaid extension on health care utilization in the year after delivery. METHODS: We conducted a retrospective cohort study of postpartum patients at an academic center in Florida whose deliveries were funded by Medicaid. The study was approved by the IRB. Health care charges were compared between Cohort I (pre-Medicaid extension 2020–2021) and Cohort II (post-extension 2022–2023). Primary outcomes were between-cohort differences in health care utilization in the year after delivery. Services were categorized by specialty and acuity. Data were analyzed using χ2 and Student's t-test. P<.5 was considered significant. RESULTS: There were 3,746 patients in Cohort I and 1,537 in Cohort II. Baseline characteristics were similar. Cohort I had 899 and Cohort II had 528 patients without health care charges (23 versus 34%; P<.001). Charges in Cohort I were more likely to occur on days 7–90 (75 versus 60.6%; P<.001), and Cohort II had more charges days 183–365 (9.9 versus 24.3%; P<.001). After postpartum Medicaid extension, health care encounters were more likely to be ambulatory (87 versus 93%; P<.001) and less likely to be inpatient (11.6 versus 4.2%; P<.001) or emergency services (0.7 versus 0.4%; P<.001). CONCLUSION: In the year after postpartum Medicaid extension, health care charges indicate increased overall utilization, with increased ambulatory care but decreased hospitalizations and emergency visits.