BACKGROUND: The linkage and barriers of linkage to facility-based HIV care from a mobile HIV testing unit have not previously been described. METHODS: A stratified random sample (N = 192) was drawn of all eligible, newly diagnosed, HIV-infected individuals with a laboratory CD4 count result on a mobile unit between August 2008 and December 2009. All individuals with CD4 counts ≤350 cells per microliter and 30% of individuals with CD4 counts >350 cells per microliter were sampled. Linkage to care was assessed during April to June 2010 in those who received their CD4 count result. A participant who accessed HIV care at least once after testing was regarded as having linked to care. Binomial regression models were used to identify clinical and socio-demographic factors associated with receiving a CD4 count result and linking to care. RESULTS: Forty-three (27%) individuals did not receive their CD4 count result. A lower CD4 count, being female, and the availability of a phone number increased the likelihood of receiving this result. Follow-up was attempted in the remaining 145 individuals. Ten refused to participate, and contact was unsuccessful in 42.4%. Linkage was 100% in patients with CD4 counts ≤200 cells per microliter, 66.7% in individuals with CD4 counts 201-350 cells per microliter, and 36.4% in those with CD4 counts >350 cells per microliter. A lower CD4 count, disclosure, symptoms of tuberculosis, and unemployment increased the likelihood of linking to care. CONCLUSION: Linkage to care was best among those eligible for antiretroviral therapy. Interventions designed at improving linkage among employed individuals are urgently warranted.