Background: Due to overnight caregiving demands; exacerbation of high rates of anxiety, depression, and distress; and inadequate support, millions of family caregivers of patients receiving in-home hospice are at risk of poor sleep and negative health effects. Aim: To describe sleep experiences of family caregivers of in-home hospice patients and perceptions of these experiences on caregivers’ wellbeing in the context of caregiver health and live-in status. Design: Developed using the Symptom Management Model, this mixed methods study featured a concurrent nested design prioritizing qualitative reflexive thematic analysis. Setting/participants: About 47 family caregivers of in-home hospice patients from two randomized clinical trials (NCT03712410, NCT02929108) were interviewed (United States, 2021). Anxiety (GAD-7), depression (PHQ-9), quality-of-life (QOL) (CQLI-R), and self-rated health and energy were reported prior to interviews. Results: Qualitative analysis revealed three themes: compromised sleep quality, factors influencing sleep, effects of sleep. 72.5% of hospice family caregivers described “fair” or “poor” sleep quality, with “ interrupted” sleep and frequent night-waking due to “ on-call” “ vigilance” and anxiety. Negative effects included exhaustion, mental and physical health decline, and reduced caregiver function. Live-in caregivers reported higher mean depression scores (8.4 vs 4.3, p = 0.08), higher mean anxiety scores (7.7 vs 3.3, p = 0.06), and lower mean QOL scores (24.8 vs 33.6, p < 0.001) than live-out caregivers. Anxiety, depression, and QOL worsened as self-reported caregiver sleep quality decreased. Few caregivers had adequate support. Conclusion: End-of-life family caregivers experience disrupted sleep with negative effects and inadequate support. Clinicians must assess sleep, offer sleep interventions, and provide more supports to hospice family caregivers.