BACKGROUND: During the COVID-19 pandemic, hospitals did not allow caregiver visitation. Little is known about how caregivers' absence affected patients' care. OBJECTIVE: This study aimed to describe visitation restrictions' impact on patients and their caregivers experiences. DESIGN: We used a sequential explanatory mixed-methods study design. First, we randomly selected 200 adult patients with cancer or heart failure hospitalized before (n = 100) and during visitor restrictions (n = 100) and abstracted data from the electronic medical record on communication between medical teams and caregivers and the topics discussed. Results from the quantitative analysis guided our thematic analysis of semi-structured interviews conducted with a subsample of patients hospitalized during visitor restrictions and their caregivers to understand the impact of visitor restrictions on their experiences. RESULTS: Compared to prerestrictions, caregivers under visitation restrictions communicated less frequently with the medical team (29% vs. 37% of hospitalized days; p = .04), fewer received discharge counseling (37% vs. 52%; p = .04), and disproportionately more had no contact with the medical team (36% vs. 17%; p < .01). Video conferencing was documented for caregivers of only five patients. Qualitative analysis revealed that both caregivers and patients experienced emotional distress, increased conflict, and decreased perception of quality of care because of visitation restrictions. CONCLUSIONS: Hospital visitor restrictions significantly reduced caregivers' communication with patients' medical team, causing caregivers and patients emotional distress. Protocols that facilitate communication between caregivers and care teams may benefit caregivers who cannot be physically present at care facilities, including distance caregivers.