Objectives: To assess Medicare beneficiaries' willingness-to-pay (WTP) for medication therapy management (MTM) services and determine sociodemographic and clinical characteristics influencing this payment amount., Design: A cross-sectional, descriptive study design was adopted to elicit Medicare beneficiaries' WTP for MTM., Setting: Nine outreach events in cities across Central/Northern California during Medicare's 2011 open-enrollment period., Participants: A total of 277 Medicare beneficiaries participated in the study., Interventions: Comprehensive MTM was offered to each beneficiary. Pharmacy students conducted the MTM session under the supervision of licensed pharmacists. At the end of each MTM session, beneficiaries were asked to indicate their WTP for the service. Medication, self-reported chronic conditions, and beneficiary demographic data were collected and recorded via a survey during the session., Results: The mean WTP for MTM was $33.15 for the 277 beneficiaries receiving the service and answering the WTP question. WTP by low-income subsidy recipients (mean ± standard deviation; $12.80 ± $24.10) was significantly lower than for nonsubsidy recipients ($41.13 ± $88.79). WTP was significantly (positively) correlated with number of medications regularly taken and annual out-of-pocket drug costs., Conclusion: The mean WTP for MTM was $33.15. WTP for MTM significantly varied by race, subsidy status, and number of prescription medications taken. WTP was significantly higher for nonsubsidy recipients than subsidy recipients, and significantly positively correlated with the number of medications regularly taken and the beneficiary rating of the delivered services.