Purpose: Informal family caregivers are increasingly recognized as critical for meeting the needs of individuals with chronic diseases associated with aging. This study examined race and gender differences in perceived informal caregiver availability for participants aged 45 and older in a large national epidemiological study. Design and Methods: Cross-sectional data were collected in structured telephone interviews from 32,999 participants from the REasons for Geographic and Racial Differences in Stroke (REGARDS) study.