Willingness to pay for forest therapy services and its determinants among adults in Republic of Korea: a nationwide double-bounded contingent valuation study

Background The diverse public-benefit functions provided by forests are non-market goods for which market prices are not established. Among these, forest therapy services, which provide physical, psychological, and social health benefits through forest environments, have attracted growing attention for alleviating stress and reducing depression and anxiety. However, quantitative studies analyzing the level of willingness to pay (WTP) for this service and its determinants remain scarce. This study applied the double-bounded dichotomous choice (DBDC) contingent valuation method (CVM), a non-market valuation approach, to estimate the WTP of the general public for forest therapy services and to analyze its determinants. Methods A hypothetical scenario was presented to 1,050 adults nationwide in September 2025. The survey collected information on WTP in the form of a per-visit service fee, along with sociodemographic characteristics, awareness and experience of forest therapy, perceived effectiveness, health and attitudinal variables, and reasons for payment refusal. The full sample of 1,050 respondents was used as the main analysis sample for DBDC CVM estimation using a logit model. Additionally, to examine the robustness of the results to protest response treatment, a robustness check was conducted on a subsample of 845 respondents, excluding 205 protest respondents identified based on their stated reasons for payment refusal. Results The estimated mean WTP for forest therapy services was KRW 15,700 (approximately USD 11.1) per visit. Household income, experience with forest therapy programs, intention to participate in future programs, presence of a condition under treatment, and forest ecological sensitivity were significantly and positively associated with WTP. Protest respondents had rejected both presented bids, and excluding them increased mean WTP to KRW 19,851 (approximately USD 14.0). In this robustness check, age group emerged as an additional significant positive determinant. Conclusion Our findings indicate that WTP for forest therapy services was more closely associated with ability to pay, actual experience, intention to participate, health status, and ecological sensitivity than with awareness or perceived effectiveness. These results provide foundational data for designing policies and programs aimed at delivering forest therapy services tailored to the characteristics of potential users.