It is not known whether recent declines in ischemic heart disease and its risk factors have been accompanied by declines in heart failure (HF) hospitalization and mortality. To examine changes in HF hospitalization rate and 1-year mortality rate in the United States, nationally and by state or territory. From acute care hospitals in the United States and Puerto Rico, 55,097,390 fee-for-service Medicare beneficiaries hospitalized between 1998 and 2008 with a principal discharge diagnosis code for HF. Changes in patient demographics and comorbidities, HF hospitalization rates, and 1-year mortality rates. The HF hospitalization rate adjusted for age, sex, and race declined from 2845 per 100,000 person-years in 1998 to 2007 per 100,000 person-years in 2008 (P < .001), a relative decline of 29.5%. Age-adjusted HF hospitalization rates declined over the study period for all race-sex categories. Black men had the lowest rate of decline (4142 to 3201 per 100,000 person-years) among all race-sex categories, which persisted after adjusting for age (incidence rate ratio, 0.81; 95% CI, 0.79-0.84). Heart failure hospitalization rates declined significantly faster than the national mean in 16 states and significantly slower in 3 states. Risk-adjusted 1-year mortality decreased from 31.7% in 1999 to 29.6% in 2008 (P < .001), a relative decline of 6.6%. One-year mortality rates declined significantly in 4 states but increased in 5 states. The overall HF hospitalization rate declined substantially from 1998 to 2008 but at a lower rate for black men. The overall 1-year mortality rate declined slightly over the past decade but remains high. Changes in HF hospitalization and 1-year mortality rates were uneven across states.