Objectives: Rising costs in oncology care often impact patients and families directly, making communication about costs and financial impacts of treatment crucial. Cost expenditures could offer opportunities for estimation and prediction, affording personalized conversations about financial impact. We sought to explore providers', patients', and caregivers' preferences towards implementing communication about cost, including when, how, and by whom such information might be provided.; Methods: We conducted semi-structured phone interviews with a diverse population including 12 oncology providers, 12 patients, and 8 patient caregivers (N = 32). The constant comparative method was used to identify mutually agreed upon themes.; Results: Participant groups differed in their concerns surrounding cost communication, namely whether they want to receive this information and how such information might impact provider and patient treatment decisions. All participants agreed that oncology providers should not be leading cost conversations. Patients and caregivers identified social workers or financial advisors as most equipped to communicate about cost. Participants emphasized timely cost conversations, ideally around the time of diagnosis. Participants favored various metrics of financial impact beyond overall costs of care including disability, days lost from work, and out-of-pocket expenses.; Conclusion: Cost transparency should be incorporated into usual care; however, there are several challenges to making cost conversations a part of everyday practice. Patients and family members need resources related to cost to aid in decision-making and those delivering cost information should have competency in oncology, financial advisement, and patient-centered care.