© 2019 Wolters Kluwer Health, Inc. All rights reserved. Background: The relationship of internalized HIV stigma to key care cascade metrics in the United States is not well established using large-scale, geographically diverse data.Setting: Center for AIDS Research Network of Integrated Clinical Systems (CNICS) cohort study. Methods: Beginning in February 2016, we administered a yearly, validated 4-item internalized HIV stigma scale (response scale 1 = strongly disagree to 5 = strongly agree, Cronbach's alpha 0.91) at 7 CNICS sites and obtained cohort data through November 2017. We compared mean stigma levels by sociodemographic characteristics and used multivariable logistic regression, controlling for the same sociodemographic covariates, to evaluate the association between mean stigma and (1) concurrent viremia; (2) missed visits; and (3) poor visit constancy. We used inverse probability weighting (IPW) to account for differences between patients who did and did not undergo stigma assessment. Results: Of 13,183 CNICS patients, 6448 (49%) underwent stigma assessment. Mean stigma was 1.99 (SD 1.07), and 28.6% agreed/strongly agreed with at least 1 stigma question. Patients younger than 50 years, racial/ethnic minorities, cis-women, and heterosexuals had higher mean stigma. Mean stigma score was associated with concurrent viremia [adjusted odds ratio (AOR) 1.13, 95% confidence interval (CI): 1.02 to 1.25, P 0.02], missed visits (AOR 1.10, 95% CI: 1.02 to 1.19, P 0.01), and poor visit constancy, although the effect on visit constancy was attenuated in the IPW model (AOR 1.05, 95% CI: 0.98 to 1.13, P 0.17). Conclusions: Higher internalized HIV stigma had a modest but statistically significant association with concurrent viremia and poor retention in care. Further inquiry with prospective analyses is warranted.