SETTING: A community-based voluntary counseling and testing (VCT) center in Moshi, Tanzania. OBJECTIVE: To compare rates of prior human immunodeficiency virus (HIV) testing among clients with and without previous tuberculosis (TB) treatment, and HIV seropositivity among those with and without current TB symptoms. DESIGN: Cross-sectional study of consecutive clients presenting for initial testing; sociodemographic and clinical data were collected via a structured questionnaire. HIV status was compared among clients with or without three or more TB-related symptoms: weight loss, fever, cough, hemoptysis or night sweats. RESULTS: Overall, 225 (3%) of 6583 VCT clients who responded to questions on previous TB treatment reported a history of TB, but only 34 (15%) reported previous HIV testing. This rate of HIV testing was not different from the rate among those clients without a history of TB (OR 0.77, P = 0.175). One hundred thirty-five (61%) clients with a history of TB were HIV-infected at VCT, compared with 17% of all clients. Of the total 6592 first-time testers who responded, 372 (6%) had at least three symptoms suggestive of TB at VCT. These symptoms were strongly associated with HIV seropositivity (OR 16.30, P < 0.001). CONCLUSION: Missed opportunities for HIV diagnosis at the time of TB treatment appear frequent in this population, underscoring the need for integration of TB and HIV diagnostic services.