BACKGROUND Compression garments are a relatively inexpensive and easy-to-implement treatment, but the longer term benefits of abdominal compression in a real-world setting are not known. In this study we sought to evaluate commercially available abdominal compression garments in a real-world setting in patients with postural orthostatic tachycardia syndrome (POTS). METHODS Participants completed four 10-minute active stand tests, with and without an abdominal compression garment, in the morning (Test #1: AM-OFF; Test #2: AM-ON) and afternoon (Test #3: PM-ON; Test #4: PM-OFF). Participants held medication that could augment heart rate (HR) and blood pressure during this 1-day study. A Holter monitor was used to record HR and participants recorded their symptoms using the Vanderbilt Orthostatic Symptom Score at the end of each standing test (range 0-90, where 0 = no symptoms). Continuous data are presented as median (25th-75th percentile). RESULTS Standing HR (103 [91-114] vs 118 [99-134], P = 0.002) and change in HR with upright posture compared with supine (27 [19-42] vs 41 [26-48], P < 0.001) were reduced, and symptoms improved (29 [16-45] vs 35 [25-60], P = 0.005), during AM-ON compared with AM-OFF. When the garment was removed after several hours of use (PM-ON vs PM-OFF), standing HR (P = 0.04), ΔHR (P = 0.01), and symptoms (P = 0.02) increased. CONCLUSIONS Commercially available abdominal compression garments reduced HR and improved symptoms both acutely and after several hours of use. Abdominal compression garments may provide a good alternative to full waist-high compression garments in patients with POTS. BACKGROUND NCT04881318.