Purpose A full‐time 24/7 caregiver is required for 100 days or longer following an allogeneic blood or marrow transplant during which time caregivers have multiple demands. Although distress in caregivers is documented, generalization is limited by small sample sizes, restricted range of assessments, and lack of information as to which caregivers may be more vulnerable to distress. The purpose of this study was to describe the peri‐transplant psychological status of a sample of caregivers of allogeneic transplant patients. Methods We assessed caregiver mood, stress, burden, and sleep using valid self‐report measures in 109 caregivers of allogeneic transplant patients prior to stem cell transplantation. Caregivers' scores were compared with norms or established cutoff scores for behavioral measures. Additionally, demographic characteristics such as age and sex were tested as predictors of distress. Results Caregivers showed significant levels of anxiety, stress, intrusion and avoidance behaviors, and poor sleep at the start of transplant compared with established norms. Younger caregivers were more distressed than older caregivers. There were no differences in levels of distress between male and female caregivers. Conclusion The peri‐transplant period is a time of heightened anxiety and distress for caregivers of allogeneic transplant patients. This study indicates that caregivers would benefit from support programs in the peri‐transplant period. Recommendations for types of support that may be helpful to caregivers are provided, but additional research is needed to validate that these programs would help caregivers providing care to patients receiving an allogeneic transplant in the peri‐transplant period. Copyright © 2013 John Wiley & Sons, Ltd.