Stigma impairs access to health care by gay, bisexual, and other men who have sex with men. Gay, bisexual, and other men who have sex with men who are open about their sexuality, or out, are more resilient to stigma than those who are not out. Outness may influence healthcare utilization and prescription of HIV pre-exposure prophylaxis to HIV-negative gay, bisexual, and other men who have sex with men. Analyzing the 2018 American Men's Internet Survey during 2019, the adjusted prevalence ratios of healthcare stigmas and outness to healthcare providers were calculated. The effect of outness on annual healthcare visits and stigma was measured. Pre-exposure prophylaxis seeking and denial by providers was quantified and stratified by outness. Of 5,794 respondents, 3,402 (58.7%) were out to their provider. Out gay, bisexual, and other men who have sex with men were less likely to experience anticipated stigma (adjusted prevalence ratio=0.75, 95% CI=0.72, 0.80) but more likely to experience enacted stigma or discrimination (adjusted prevalence ratio=1.23, 95% CI=1.18, 1.28). In a subsample of out gay, bisexual, and other men who have sex with men, recently experienced discrimination was associated with higher healthcare utilization (adjusted prevalence ratio=1.51, 95% CI=1.14, 1.51). Conversely, recent experienced discrimination was associated with lower healthcare utilization in not out gay, bisexual, and other men who have sex with men (adjusted prevalence ratio=0.67, 95% CI=0.54, 0.82). Of 3,104 out gay, bisexual, and other men who have sex with men, 1,417 (45.7%) discussed pre-exposure prophylaxis with their providers, compared with 120 of 1,711 (7.0%) gay, bisexual, and other men who have sex with men who were not out (p<0.001). Pre-exposure prophylaxis denials were less common among out (116/793, 14.6%) than not out (14/55, 25.5%) gay, bisexual, and other men who have sex with men (p=0.044). Healthcare provider-related stigmas impair healthcare engagement among not out gay, bisexual, and other men who have sex with men who were also more commonly denied pre-exposure prophylaxis. Ending the HIV epidemic necessitates creating safe environments for disclosure of sexual preferences and practices to facilitate access to HIV prevention.