Patients experiencing premature cardiovascular events (males: <55 years; females: <65 years) represent a high-risk subgroup within the atherosclerotic cardiovascular disease (ASCVD) population. Elevated lipoprotein(a) (Lp[a]) is an independent, genetic, causal risk factor for ASCVD. Lp(a) distribution among patients with premature ASCVD is poorly characterized. We identified 17,594 patients with premature ASCVD who had Lp(a) values from US Medicare, Medicaid, and commercial plans between January 2016–September 2022. Mean age (SD) was 50.9 (10.1) years, most patients were female (68.9%), and half (52.2%) were not prescribed lipid-lowering therapy. Lp(a) levels ≥125, ≥175, and ≥225 nmol/L occurred in 26.8%, 18.8%, and 11.5%, respectively. Black patients had higher median (Q1–Q3) Lp(a) levels (111.0 [51.1–206.0] nmol/L), than Asian (35.0 [14.4–100.0] nmol/L), Hispanic (31.0 [10.9–95.0] nmol/L), or White patients (31.0 [10.7–110] nmol/L). In one of the largest studies in the US investigating Lp(a) distribution in premature ASCVD, we found over a quarter of patients had elevated Lp(a) (≥125 nmol/L).