Abstract We hypothesized that the contingent valuation method (CVM) can enhance the procedural justice of policy formation as perceived by people generally, which in turn increases public acceptance of policy. In Study 1, a survey ( n =484) asked whether respondents would accept a one-off tax, the purpose of which would be to protect the natural environment of Yakushima Island, Japan. In one condition, the respondents were told that the amount of the one-off tax was determined using the CVM. In a second condition, no such instruction was given. In Study 2, 55 subjects were asked to indicate their acceptance, or otherwise, of a one-off tax for the protection of the natural environment of Yakushima Island when the tax was determined using the CVM, and when the tax was determined using cost–benefit analysis. The data from the survey and the experiment confirmed the hypothesis that the CVM enhanced the perceived procedural justice and acceptance of the tax.