OBJECTIVE: In high HIV-burden countries like Uganda, financing and resource allocation for HIV services have rapidly evolved. This study aimed to employ time-driven activity-based costing (TDABC) to examine the allocation of resources and associated costs for HIV care throughout the country. DESIGN: A cross-sectional study. SETTING: This study was conducted at 31 health facilities throughout Uganda: 16 level III health centres, 10 level IV health centres and 5 district hospitals. PARTICIPANTS: 1119 persons receiving HIV services in 2020. METHODS: We conducted TDABC to quantify costs, resource consumption and duration of service provision associated with antiretroviral therapy, prevention of mother-to-child transmission, HIV counselling and testing (HCT), voluntary medical male circumcision (VMMC) and pre-exposure prophylaxis. We also quantified disparities in resource consumption according to client-level and facility-level characteristics to examine equity. Fixed-effects multivariable regression analyses were employed to inspect factors associated with service costs and provider-client interaction time. RESULTS: The mean cost of services ranged from US$8.18 per visit for HCT to US$32.28 for VMMC. In terms of disparities, those in the Western region received more provider time during visits compared with other regions (35 more minutes, p<0.001); and those receiving care at private facilities received more provider time compared with public facilities (13 more minutes, p=0.02); and those at level IV health centres received more time compared with those at level III (12 more minutes, p=0.01). Absent consumables, services for older adults (US$2.28 higher, p=0.02), those with comorbidities (US$1.44 higher, p<0.001) and those living in the Western region (US$2.88 higher, p<0.001) were more expensive compared with younger adults, those without comorbidities and those in other regions, respectively. Inclusive of consumables, services were higher-cost for individuals in wealthier households (US$0.83 higher, p=0.03) and those visiting level IV health centres (US$3.41 higher, p=0.006) compared with level III. CONCLUSIONS: Costs and resources for HIV care vary widely throughout Uganda. This variation requires careful consideration: some sources of variation may be indicative of vertical and horizontal equity within the health system, while others may be suggestive of inequities.