AbstractStudies of terrorism‐related deaths are few and mostly focus on short‐term effects. To characterize long‐term bereavement outcomes, including resilience/recovery and patterns of comorbidity, following the September 11, 2001 (9/11), terrorist attacks, we report mental health conditions and grief‐related impairment in 454 9/11 bereaved family members. In addition, the contribution of non‐9/11 lifetime traumas, pre‐9/11 mental health conditions, post‐9/11 interim life events, grief services, income adequacy, and social support were examined. Latent class analyses yielded three groups: healthy, comorbid without PTSD (comorbid/noPTSD), and comorbid with PTSD and impaired (comorbid/PTSD+I). Participants in the healthy group (66.1%) were least likely to meet thresholds for mental conditions, whereas those in the comorbid/noPTSD (21.3%) and comorbid/PTSD+I (12.6%) groups had higher probabilities of meeting depression, grief, and anxiety thresholds. These groups also endorsed more negatively valenced post‐9/11 interim life events than the healthy group: comorbid/noPTSD vs. healthy, odds ratio (OR) = 0.84, 95% CI [0.76, 0.94]; comorbid/PTSD+I vs. healthy, OR = 0.85, 95% CI [0.76, 0.96]. Comorbid/PTSD+I was the only group with elevated probabilities of meeting clinical thresholds for PTSD (.64) and grief‐related impairment (.94). This group was also more likely to include bereaved parents: comorbid/PTSD+I vs. healthy, OR = 12.96, 95% CI [1.97, 85.41]; comorbid/PTSD+I vs. comorbid/noPTSD, OR = 15.55, 95% CI [1.63, 148.41]); and to experience more non‐9/11 lifetime traumas: comorbid/PTSD+I vs. healthy, OR = 4.34, 95% CI [1.28, 14.70]; comorbid/PTSD+I vs. comorbid/noPTSD, OR = 6.54, 95% CI [1.53, 27.95]. Clinical and community programs should target this high‐risk group to identify individuals in need of services.