Objectives: We aimed to ascertain how frequently Australian general practitioners (GPs) test patients for chlamydia and to determine GP, patient and encounter characteristics where tests occurred. Methods: We identified all GP, patient and encounter characteristics associated with higher testing rates, April 2000 to March 2007, using the Bettering the Evaluation and Care of Health data. Multiple logistic regression was used to measure the effect of each GP, patient and encounter characteristic. Results: Data were available for 689 000 encounters from 6890 GPs, of which 2236 were test encounters. Testing rates increased significantly between 2000 and 2007 (P < 0.0001). The rate of testing was higher for female patients (4.2 per 1000, 95% confidence interval (CI): 3.8–4.5) than males (2.0; 95% CI: 1.8–2.2). Predictors of higher chlamydia testing were: female GP (adjusted odds ratio (AOR): 1.84; 95% CI: 1.60–2.1); GP age (<35 v. 55+, 2.17; 95% CI: 1.65–2.85); practice in a major city (1.34; 95% CI: 1.18–1.52); large practice (5+ GP practice v. solo, 1.69; 95% CI: 1.27–2.25); graduated in Australia (1.22; 95% CI: 1.04–1.44); patient sex and younger age, being new to the practice (1.65; 95% CI: 0.47–1.86), Indigenous (3.46; 95% CI: 2.64–4.54), late in the study (twice as likely in 2006–07 than in 2000–01) and ‘opportunity to test’ (AOR: 32.25; 95% CI: 27.25–38.16). Conclusions: Chlamydia testing rates have increased in general practice in Australia, with higher rates in females. Initiatives to overcome barriers to testing (especially for male patients and older male GPs) need to be established and evaluated.