OBJECTIVES National estimates of cardiovascular risk factor prevalence, awareness, treatment, and control among adults without health insurance are lacking. This study contributes to our knowledge by examining current national estimates for hypertension, dyslipidemia, and diabetes among uninsured, non-Medicaid insured, and Medicaid-insured adults aged 18 through 64 years. METHODS Cross-sectional observational study design. Analysis of adults 18 through 64 years of age surveyed in the National Health and Nutrition Examination Survey (NHANES) 2003-2006 (N=8,500). RESULTS Of an estimated 178.6 million working-age adults, 21.8% (95% confidence interval [CI] = 19.6%- 24.1%) lack health insurance. Hypertension prevalence is significantly lower in the uninsured compared with the non-Medicaid insured (18.9% and 21.8%, age and gender adjusted) as are rates of awareness (62.8% vs 77.0%) and treatment (43.9% vs 65.5%). Medicaid-insured adults have a significantly higher prevalence of hypertension (29.1%) than the non-Medicaid insured. There is no significant difference between the uninsured and non-Medicaid insured with respect to adjusted prevalence of dyslipidemia (27.4% and 25.3%) or type-2 diabetes (6.4% and 6.0%). Awareness and treatment rates for dyslipidemia are significantly lower in the uninsured compared with the non-Medicaid insured (38.8% vs 64.7% for awareness; 18.0% vs 41.4% for treatment). Treatment rates for diabetes are also significantly lower for the uninsured (39.9% vs 62.5%). Multivariable logistic regression controlling for age, gender, race, education, access to care, and marital status indicate that the uninsured are significantly less likely than the non-Medicaid insured to be aware of and treated for their dyslipidemia and less likely to be treated for their diabetes. CONCLUSIONS Dyslipidemia and diabetes are less likely to be detected or treated among the uninsured compared with the non-Medicaid insured, calling for effective approaches to reduce these disparities.