BACKGROUND: For frail patients with limited life expectancy, time in hospital following transcatheter aortic valve replacement is an important measure of quality of life; however, data remain scarce. Thus, we aimed to investigate frailty and its relation to time in hospital during the first year after transcatheter aortic valve replacement. METHODS AND RESULTS: From 2008 to 2020, all Danish patients who underwent transcatheter aortic valve replacement and were alive at discharge were included. Using the validated Hospital Frailty Risk Score, patients were categorized in the low, in-termediate, and high frailty groups. Time in hospital and mortality up to 1 year are reported according to frailty groups. In total, 3437 (57.6%), 2277 (38.1%), and 257 (4.3%) were categorized in the low, intermediate, and high frailty groups, respectively. Median age was ≈81 years. Female sex and comorbidity burden were incrementally higher across frailty groups (low frailty: heart failure, 24.1%; stroke, 7.2%; and chronic kidney disease, 4.5%; versus high frailty: heart failure, 42.8%; stroke, 34.2%; and chronic kidney disease, 29.2%). In the low frailty group, 50.5% survived 1 year without a hospital admission, 10.8% were hospitalized >15 days, and 5.8% of patients died. By contrast, 26.1% of patients in the high frailty group survived 1 year without a hospital admission, 26.4% were hospitalized >15 days, and 15.6% died within 1 year. Differences persisted in models adjusted for sex, age, frailty, and comor-bidity burden (excluding overlapping comorbidities). CONCLUSIONS: Among patients undergoing transcatheter aortic valve replacement, frailty is strongly associated with time in hospital and mortality. Prevention strategies for frail patients to reduce hospitalization burden could be beneficial.