A systematic review of patient retention in antiretroviral therapy (ART) programs in sub-Saharan Africa found that, on average, 77.5% of patients were retained after 9.9 months of follow-up. At 6, 12, and 24 months, retention rates were estimated at 79.1%, 75.0%, and 61.6%, respectively. However, these rates may be overestimated due to shorter reporting periods and the use of extrapolated data. The highest retention rate was 85% in one program, while the lowest was 46%. Attrition was primarily due to loss to follow-up (56%) and death (40%). Programs with shorter follow-up periods had higher attrition rates, suggesting that longer follow-up periods may provide more accurate retention estimates. Sensitivity analyses indicated that actual retention rates after two years could range from 24% to 77%, with a plausible midpoint of 50%. The study highlights the importance of improving patient tracing, understanding loss to follow-up, and early ART initiation to enhance retention. Retention varied widely across programs, with some achieving higher retention rates. The findings suggest that African ART programs retain about 60% of patients after two years, with significant heterogeneity in retention rates. Loss to follow-up is the major cause of attrition, followed by death. The study underscores the need for better patient tracking and strategies to improve retention in ART programs.A systematic review of patient retention in antiretroviral therapy (ART) programs in sub-Saharan Africa found that, on average, 77.5% of patients were retained after 9.9 months of follow-up. At 6, 12, and 24 months, retention rates were estimated at 79.1%, 75.0%, and 61.6%, respectively. However, these rates may be overestimated due to shorter reporting periods and the use of extrapolated data. The highest retention rate was 85% in one program, while the lowest was 46%. Attrition was primarily due to loss to follow-up (56%) and death (40%). Programs with shorter follow-up periods had higher attrition rates, suggesting that longer follow-up periods may provide more accurate retention estimates. Sensitivity analyses indicated that actual retention rates after two years could range from 24% to 77%, with a plausible midpoint of 50%. The study highlights the importance of improving patient tracing, understanding loss to follow-up, and early ART initiation to enhance retention. Retention varied widely across programs, with some achieving higher retention rates. The findings suggest that African ART programs retain about 60% of patients after two years, with significant heterogeneity in retention rates. Loss to follow-up is the major cause of attrition, followed by death. The study underscores the need for better patient tracking and strategies to improve retention in ART programs.