Increasing demand for antiretroviral treatment (ART) together with a reduction in international funding during the last decade may jeopardize access to ART. Using data from a cross-sectional survey conducted in 2014 in 19 HIV services in the Centre and Littoral regions in Cameroon, we investigated the role of healthcare supply-related factors in time to ART initiation in HIV-positive patients eligible for ART at HIV diagnosis. HIV service profiles were built using cluster analysis. Factors associated with time to ART initiation were identified using a multilevel Cox model. The study population included 847 HIV-positive patients (women 72%, median age: 39 years). Median (interquartile range) time to ART initiation was 1.6 (0.5-4.3) months. Four HIV service profiles were identified: (1) small services with a limited staff practising partial task-shifting (n = 4); (2) experienced and well-equipped services practising task-shifting and involving HIV community-based organizations (n = 5); (3) small services with limited resources and activities (n = 6); (4) small services providing a large range of activities using task-shifting and involving HIV community-based organizations (n = 4). The multivariable model showed that HIV-positive patients over 39 years old [hazard ratio: 1.26 (95% confidence interval) (1.09-1.45), P = 0.002], those with disease symptoms [1.21 (1.04-1.41), P = 0.015] and those with hepatitis B co-infection [2.31 (1.15-4.66), P = 0.019] were all more likely to initiate ART early. However, patients in the first profile were less likely to initiate ART early [0.80 (0.65-0.99), P = 0.049] than those in the second profile, as were patients in the third profile [association only significant at the 10% level; 0.86 (0.72-1.02), P = 0.090]. Our findings provide a better understanding of the role played by healthcare supply-related factors in ART initiation. In HIV services with limited capacity, task-shifting and support from community-based organizations may improve treatment access. Additional funding is required to relieve healthcare supply-related barriers and achieve the goal of universal ART access.