Most studies of heart failure (HF) in Medicare beneficiaries have excluded patients age <65years. We examined baseline characteristics, quality of care, and outcomes among younger and older Medicare beneficiaries hospitalized with HF in the Alabama Heart Failure Project.Of the 8049 Medicare beneficiaries discharged alive with a primary discharge diagnosis of HF in 1998–2001 from 106 Alabama hospitals, 991 (12%) were younger (age <65years). After excluding 171 patients discharge to hospice care, 7867 patients were considered eligible for left ventricular systolic function (LVSF) evaluation and 2211 patients with left ventricular ejection fraction <45% and without contraindications were eligible for angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) therapy.Nearly half of the younger HF patients (45% versus 22% for ≥65years; p<0.001) were African American. LVSF was evaluated in 72%, 72%, 70% and 60% (overall p<0.001) and discharge prescriptions of ACE inhibitors or ARBs were given to 83%, 77%, 75% and 75% of eligible patients (overall p=0.013) among those <65, 65–74, 75–84 and ≥85years respectively. During 9years of follow-up, all-cause mortality occurred in 54%, 61%, 71% and 80% (overall p<0.001) and hospital readmission due to worsening HF occurred in 65%, 60%, 55% and 48% (overall p<0.001) of those <65, 65–74, 75–84 and ≥85years respectively.Medicare beneficiaries <65years with HF, nearly half of whom were African American generally received better quality of care, had lower mortality, but had higher re-hospitalizations due to HF.