BACKGROUND: Cost-related nonadherence compromises successful and effective management of chronic disease. The Medicare Modernization Act of 2003 (MMA) and Patient Protection and Affordable Care Act of 2010 (ACA) aimed to increase the affordability of outpatient prescription drugs for older adults (older than age 64 years). The Medicare Part D prescription drug insurance coverage gap ("donut hole") created by the MMA was fully closed in 2020 by the ACA. OBJECTIVES: To (1) describe prescription drug coverage and financial hardship from purchasing prescription drugs among older American adults for 2021, (2) compare these results with findings from data collected before the MMA and during the progressive elimination of the Medicare Part D coverage gap, and (3) compute the likelihood for financial hardship from purchasing prescription drugs using variables for year, prescription drug insurance coverage, health-related information, and demographics. METHODS: Data were obtained from 4 nationally distributed, crosssectional surveys of older adults to track coverage for and financial hardship from purchasing prescription drugs. Surveys in 1998 and 2001 were mailed to national random samples of US seniors. Of 2,434 deliverable surveys, 700 (29%) provided useable data. Data were collected in 2015 and 2021 via online surveys sent to samples of US adults. Of 27,694 usable responses, 4,445 were from older adults. Descriptive statistics and logistic regression analyses described relationships among financial hardship and demographics, diagnoses, and daily prescription drug use. RESULTS: Five percent of older adults lacked prescription drug coverage in 2021, continuing a downward trend from 32% in 1998, 29% in 2001, and 9% in 2015. Contrastingly, 20% of older adults reported financial hardship from prescription drug purchases in 2021, bending an upward trend from 19% in 1998, 31% in 2001, and 36% in 2015. Financial hardship from purchasing prescription drugs was more likely to be reported by older adults lacking prescription drug insurance, taking multiple medications daily, and having a low annual household income across all survey years. The latter 2 of these 3 factors were still predictive of financial hardship from purchasing prescription drugs among older adults with prescription drug insurance. CONCLUSIONS: Financial hardship from purchasing prescription drugs is still experienced by many older adults after the full implementation of the MMA and ACA. Lacking prescription drug coverage, taking more than 5 prescription drugs daily, and a low annual household income may increase the likelihood of experiencing this financial hardship. Pharmacists can be a resource for older adults making choices about their prescription drug coverages and purchases. DISCLOSURES: Funding was provided by the American Association of Colleges of Pharmacy New Investigator Program, the University of Minnesota Grant-in-Aid of Research Program, the Peters Endowment for Pharmacy Practice Innovation, the Chapman University Research Program, and the University Minnesota Research Program.