Stigmatization of HIV infection undermines antiretroviral therapy (ART) adherence. The current study examined strategies that people living with HIV employ to manage their ART in stigmatized environments. We conducted an anonymous survey with 439 patients receiving ART at a community clinic in Cape Town, South Africa. Measures included demographic and health characteristics, ART adherence, stigma experiences, efforts to conceal ART to avoid stigma (stigma–medication management strategies), and beliefs that ART nonadherence itself is stigmatizing. One in four participants had forgone taking their ART in social settings to avoid stigmatization, a behavior associated with younger age, experiencing greater stigma, and poorer ART adherence. Regression models found stigma–medication management strategies significantly predicted ART nonadherence over and above age, gender, alcohol use, and HIV stigma experiences. We also found that a significant majority of participants believed that having unsuppressed HIV and ART nonadherence are irresponsible and should be reprimanded by clinicians. Results show that the behavioral effects of stigma directly impede ART adherence. The behaviors that patients may employ to avoid stigma are amenable to interventions to directly improve ART adherence while managing stigma concerns.