Rates of chlamydia testing and detection were analysed for an urban region of New Zealand from 1999 to 2005. Females were tested five times more often than males, but had lower rates of chlamydia diagnoses (OR 0.4; 95% CI 0.39 to 0.42). Rates of chlamydia detection were significantly higher in Pacific people (OR 2.33; 95% CI 2.16 to 2.5) and Māori (OR 2.01; 95% CI 1.87 to 2.17) than in Europeans. Individuals living in areas of greater socioeconomic deprivation also had higher rates of chlamydia (OR 1.66; 95% CI 1.55 to 1.77). Chlamydia diagnoses were significantly higher in individuals under 25 years, with the highest positive diagnoses in the 15–19 year age group (OR 9.06; 95% CI 8.23 to 9.98). The authors concluded that appropriate chlamydia control programs are urgently needed in New Zealand, with testing targeted to higher-risk groups who appear to be currently underserved.