Participants and their families routinely ask what a trial will cost them, and the answer is rarely simple. This session offers practical, plain-language approaches for explaining which items are billed to insurance, which are covered by the sponsor, and what out-of-pocket costs a participant might still face. We will cover how to align what the consent form says with what the billing office actually does, how to handle deductible and coinsurance questions, and how to respond when a participant receives an unexpected bill. The session also addresses stipends, travel reimbursement, and their tax implications. Attendees will gain scripts and talking points they can adapt for their own sites.