Timely detection of congenital anomalies using ultrasound improves neonatal care. As specialist sonographers are often geographically dispersed, they are sometimes requested to provide a second opinion via tele-expertise. The present study aimed to evaluate the economic impact of asynchronous tele-expertise in obstetric ultrasound care in private medical practice through a comparison with face-to-face consultations. We conducted a cost minimization analysis using decision tree modeling in order to determine whether asynchronous tele-expertise or face-to-face consultation had the lowest cost, under the assumption of equivalent effectiveness in terms of prenatal diagnosis. Costs were measured from the societal perspective. The data for the base case of our modeling came from a retrospective analysis of the clinical practice of an expert who had been conducting asynchronous tele-expertise for 4 years in France. The study included 260 patients for whom 322 requests for expert opinions were made by physicians/midwives from January 2016 to January 2020. The expected average total cost for tele-expertise for a patient was €74.45 (95% CI: €66.36–€82.54) compared to €195.02 (95% CI: €183.90–€206.14) for the conventional face-to-face strategy. Accordingly, using tele-expertise led to a statistically significant reduction of €120.57 in the average total cost per patient. A sensitivity analysis confirmed the robustness of the model produced. The results of the present study underline the efficiency of tele-expertise and highlight related economic benefits. Accordingly, they could inform public health policy on the dissemination of tele-expertise in the field of obstetric ultrasound care.