Decision-making errors such as present bias (PB) can have important consequences for health behaviors, but have been largely studied in the financial domain. We conducted a mixed-method study on PB in the context of ART adherence among clinic-enrolled adults in Uganda (n = 39). Specifically, we quantified PB by asking about preferences between medication available sooner to minimize headaches versus available later to cure headaches. We describe demographic similarities among PB participants and qualitatively explored how participants reflected on their PB (or absence thereof) in the context of health. Participants reporting PB were predominantly male, single/unmarried, older, had higher levels of education and income and more advanced HIV progression. Three common reasons for more present-biased choices provided were: (1) wanting to avoid pain, (2) wanting to return to work, and (3) fear of one’s health worsening if s/he did not address their illness immediately. While PB in the financial domain often suggests that poorer individuals are more likely to prefer immediate rewards over their wealthier counterparts, our results suggest poor health is potentially a driving factor of PB. Further research is needed to build on these finding and inform how programs can frame key messages regarding ART adherence to patients displaying PB. Trial registration: ClinicalTrials.gov identifier: NCT03494777.