A nationwide, random-sampled and population-weighted telephone survey was conducted in Japan. The sample size of respondents was 1000. Using a region-, gender- and age-weighted sampling table, professional operators called respondents using random-digit dialling. Respondents were asked questions about their use of CAM in the past 12 months, out-of-pocket expenditures on CAM and orthodox Western medicine, reasons for the use of CAM, and so on, as well as general socio-demographics. The percentage of respondents that had used at least one CAM therapy in the past 12 months was greater than those that had used orthodox Western medicine [76.0% 95% confidence interval (CI) 73.4–78.6, vs. 65.6%, 95% CI 62.7–68.5). The use for each CAM therapy was as follows: nutritional and tonic drinks, 43.1%; dietary supplements, 43.1%; health-related appliances, 21.5%; herbs or over-the-counter Kampo, 17.2%; massage or acupressure, 14.8%; ethical Kampo (Kampo prescribed by medical doctors), 10.0%; aromatherapy, 9.3%; chiropractic or osteopathy, 7.1%; acupuncture and moxibustion, 6.7%; homoeopathy, 0.3%; and other therapies, 6.5%. Regarding the reasons for the use of CAM, 60.4% responded that ‘the condition was not serious enough to warrant orthodox Western medicine’, and 49.3% were ‘expecting health promotion or disease prevention’. Average annual out-of-pocket expenditures of all the 1000 respondents for CAM were half as much as those for orthodox Western medicine (19 080 yen, 95% CI 15 824–22 336, vs. 38 360 yen, 95% CI 30 439–46 280).