This study was conducted to describe voluntary HIV testing in the general population in Switzerland and to estimate yearly HIV test incidence. In 1994, a representative telephone survey of individuals aged 17 to 45 years obtained self-reported information on HIV testing. In addition to describing cumulative HIV test incidence, yearly HIV test incidence over time was estimated by a Bayesian hurdle model allowing for the plausible scenario of test consumption differing between first test and subsequent retests. Overall, 33% of the Swiss population (age 17 to 45 years) has been tested at some time for HIV on a voluntary basis (30% men, 36% women). For the time period 1990-1994, the result showed for 35-year-old individuals with supposedly low risk behavior, that 1) annual test incidence (first test or retest) showed a greater increase for men (4.2 to 5.9%) than for women (5.0 to 6.0%); 2) annual first test incidence increased moderately and differed for men and women (2.9 to 3.4% for men, 4.6 to 5.2% for women), and 3) annual retest incidence was twice as high for men (17.6%) as for women (8.6%). In conclusion, a substantial part of the Swiss population has been tested at some stage for HIV on a voluntary basis, and differences exist for testing and retesting between men and women.