Hematopoietic cell transplant (HCT) can cause significant distress in patients and their informal caregivers. Despite advances in reduced-intensity conditioning and supportive care, few recent studies have reported rates of clinically significant post-traumatic stress disorder (PTSD) symptomatology. Goals of the current study were to examine rates of PTSD and distress in patients and caregivers and to identify sociodemographic and clinical risk factors for PTSD. As part of an annual survivorship survey, 2157 HCT recipients and their caregivers were mailed self-report measures of PTSD and distress. Patients also completed self-report measures of sociodemographic information (eg, age, sex, employment status). Clinical variables (eg, time since transplant, transplant type) were captured in the transplant database. A total of 691 recipients (56% age 60 or above at the time of survey, 47% women, median 10.1 years post-HCT) and 333 caregivers provided PTSD data and were included in the current analyses. More caregivers reported PTSD (6.6%) than patients (3.3%; P =.02). Patients or caregivers who had PTSD reported significantly higher distress related to uncertainty, family strain, medical demands, finances, identity, and health burden (P <.0001) compared with those without PTSD. Patient but not caregiver PTSD was associated with more recent transplant (P =.01 and P =.16, respectively). Rates of PTSD are relatively low in long-term survivors of HCT and their caregivers. Nevertheless, results are consistent with other studies of cancer caregiving suggesting that caregivers often experience greater distress than patients. Timely referral to psychosocial services should be offered to both HCT recipients and caregivers reporting symptoms of PTSD.