Family and friends are the predominant providers of end-of-life care (EOL). Yet knowledge of the caregiving experience at the EOL has been constrained by a narrow focus on specific diseases or the “primary” caregiver and methodological limitations due to reliance on convenience samples, or recall biases associated with mortality follow-back study design. Using prospective, linked nationally representative datasets of Medicare beneficiaries and their caregivers, we found that in 2011 900,000 older adults at the EOL received support from 2.3 million paid and unpaid caregivers. Nearly 9 in 10 of these caregivers were family members or unpaid. EOL caregivers provided more extensive care and reported more care-related challenges (e.g., physical difficulty) than non-EOL caregivers. EOL challenges were especially prevalent among caregiving spouses. To meet the needs of older adults at the EOL, families and unpaid caregivers must be better recognized and integrated in care delivery and supportive services must be expanded and made more widely available.