Objectives: Universal Test and Treat (UTT) strategies are being adopted across sub-Saharan Africa based on clinical benefits to morbidity and mortality and to attain targets of the Joint United Nations Programme on HIV/AIDS (UNAIDS). Universal Test and Treat is expected to change the client population at clinics, due to more asymptomatic HIV clients initiating antiretroviral therapy (ART). We assessed the impact of UTT on client appointment adherence at 14 government-managed health facilities in Eswatini's public sector health system. Methods: We assessed the impact of UTT on client adherence to appointment schedules from 2014 to 2017 in a stepped-wedge trial. Repeated measures analysis was used to assess adherence to each scheduled appointment (primary definition: presenting for care within 7 days after the scheduled appointment), adjusting for time, age, sex, stage, marital status, ART status and facility. Results: Among 3354 clients (62.1% female; 57.4% < 35 years), a median (interquartile range) of 10 (6-15) appointments were scheduled during follow-up. In a multivariable-adjusted model, appointment adherence was significantly greater in clients who were female [odds ratio (OR) = 1.38, 95% confidence interval (CI): 1.25-1.52], older (e.g. 40 to < 50 years vs. < 20 years; OR = 1.45, 95% CI: 1.00-2.09), married (OR = 1.31, 95% CI: 1.19-1.44), had lower WHO stage at study enrolment (1-2 vs. 3-4: OR = 1.26, 95% CI: 1.13-1.41), and were currently on ART (OR = 3.55, 95% CI: 2.62-4.82). However, UTT strategy was not significantly associated with client adherence to scheduled appointments (OR = 1.02, 95% CI: 0.72-1.45). Conclusions: Despite transitioning to UTT, there was no change in visit adherence, a reassuring finding given the large volume of clients currently being initiated at earlier stages of HIV.