Objective To determine young women’s experience of having a chlamydia (Chlamydia trachomatis) test as part of a chlamydia incidence study, and to determine how women who tested positive during the study experienced having a test compared with the experience of women who always tested negative. Methods: Women in an Australian chlamydia incidence study were tested at 3- to 6-monthly intervals during a 12-month period. At the final stage of the study, the women completed a questionnaire about how they felt about testing positive or how they anticipated they might feel about testing positive if they only tested negative. Questions about future sexual behaviour and testing were included. Results: The questionnaire was completed by 872 out of 1116 (78%) women, including 67 women who tested positive. Many women (75%) felt anxious when having a chlamydia test but women who tested positive were less concerned about their future health (61% v. 81%, P < 0.01), were less concerned about their partner’s reactions (62% v. 79%, P < 0.01) and were more likely to discuss their diagnosis with other people (57% v. 36%, P < 0.01). Conclusions: The participants in the study were pleased to have been tested and supported a screening program. Women who tested positive were less concerned about having a positive result than women who tested negative anticipated they might be. Implications: Clinicians need to be aware that having a chlamydia test can cause anxiety in young women and for a screening program to be successful, this must be addressed.