Financial reimbursement programs (FRPs) offset out-of-pocket (OOP) expenses from therapeutic clinical trial (TCT) participation. The study explores patients' experience in TCTs after enrollment in a FRP at two academic medical centers, including barriers and opportunities to improve trial participation. From May 2019 to January 2020, adults diagnosed with cancer and eligible for TCTs and FRP were recruited from the Improving Patient Access to Cancer Clinical Trials randomized trial at the University of California San Francisco and University of Southern California. Patients with income ≤ 700% of national poverty guidelines were eligible. Semistructured interviews were conducted in patients' preferred language. Qualitative analysis was performed by site and preferred language by two independent coders. Of 65 trial patients, 53 participated (38%, University of California San Francisco; 62%, USC). The median age was 59 (IQR, 46-65) years, and 58% were female. Nearly half (49%) identified as Latinx/Hispanic compared with 32% non-Hispanic White, 10% Asian, 4% Black, 1% Native American, and 4% Others. A third were non-English speakers, 42% had college education or more, and 55% were retired/unemployed. Most common malignancies were gastrointestinal (42%), breast (19%), and genitourinary (13%), and 66% had metastatic disease. Patients experienced long travel time (1-4.5 hours) among 57% and financial toxicity from OOP costs (68%). High acceptability of the FRP was reported (81%). Although 30% of patients reported willingness to discuss finances of cancer treatment/trial with physicians, majority (87%) preferred discussion with social workers or TCT staff. Proposed modifications to TCTs included decentralization, recruitment strategies, voucher structure, and established rates for OOP expenses. Patients' experience with TCTs reveal financial and logistical stressors that may be lessened by the Improving Patient Access to Cancer Clinical Trial reimbursement program. FRPs may address inequities in clinical trial access among low-income and diverse populations.