OBJECTIVE This study uses novel methods to examine the frequency of diagnosis and treatment of prediabetes in real-world clinical settings using electronic health record (EHR) data. RESEARCH DESIGN AND METHODS We identified a cohort of 358,120 adults with incident prediabetes (fasting plasma glucose [FPG] 100-125 mg/dL or glycated hemoglobin 5.7-6.4% [39-46 mmol/mol]) between 2006 and 2010 and examined rates of diagnosis and treatment in the 6 months after identification. RESULTS In the 6 months after identification of prediabetes, 18% of patients had their blood glucose levels retested; 13% received a physician diagnosis of prediabetes/hyperglycemia; 31.0% had prediabetes, diabetes, or lifestyle documented in the clinical notes; and <0.1% initiated metformin. Among patients with FPG 120-125 mg/dL, 31% were retested; metformin initiation remained <1%. CONCLUSIONS Documented rates of follow-up and treatment for prediabetes are low. EHR data may be a valuable tool to improve identification and treatment of prediabetes in the U.S.