Background: The introduction of HAART has produced dramatic clinical improvements and quality of life in patients living with HIV/AIDS. Financial access to healthcare services is critical for survival. Currently little is known about direct costs to patients before and during regular access to care services. In the absence health insurance direct costs can be a significant barrier to financial access to care services. Objectives: To assess improvements in CD4 cell count and viral load and also determine direct costs associated with various HAART regimens as well as affordability of direct costs. Methods: This cross sectional study has both retrospective and prospective components. A total of 867 out of 5000 case notes that met inclusion criteria were selected by systematic random sampling. Direct costs were obtained from relevant departments and structured questionnaire. Data were entered into SPSS 20 and analyzed using one way anova with post hoc, student t test and Chi square as appropriate. P values ≤ 0.05 were considered significant. Results and Discussion: The most prescribed regimens were those containing Zidovudine+Lamivudine+Nevirapin e (Regimen I) and Tenofovir+Lamivudine/Emtricitabine+Efavirenz (Regimen IV) accounting for 38.4% and 49.1% respectively. Improvement in CD4 and viral load is significant across all regiments. The mean direct costs ranged between US$182.9-504.5 per encounter, which makes it highly unaffordable to majority of patients. Conclusion: Clinical improvement across all the HAART regimens is significant. Direct costs are highly unaffordable and this may impact negatively on access to care services.