Non-fatal traffic accidents may give rise to mental health problems, including posttraumatic stress (PTS) and depression. Clinical evidence suggests that victims may also experience grief reactions associated with the sudden changes and losses caused by such accidents. The aim of this study was to examine whether there are unique patterns of symptoms of PTS, depression, and grief among victims of non-fatal traffic accidents. We also investigated associations of emerging symptom patterns with sociodemographic variables and characteristics of the accident, and with transdiagnostic variables, including self-efficacy, difficulties in emotion regulation, and trauma rumination. Participants (N = 328, Mage = 32.6, SDage = 17.5 years, 66% female) completed self-report measures tapping the study variables. Using latent class analysis (including symptoms of PTS, depression, and grief), three classes were identified: a no symptoms class (Class 1; 59.1%), a moderate PTS and grief class (Class 2; 23.1%), and a severe symptoms class (Class 3; 17.7%). Summed symptom scores and functional impairment were lowest in Class 1, higher in Class 2, and highest in Class 3. Psychological variables were similarly ordered with the healthiest scores in Class 1, poorer scores in Class 2, and the worst scores in Class 3. Different sociodemographic and accident related variables differentiated between classes, including age, education, and time since the accident. In a regression including all significant univariate predictors, trauma rumination differentiated Class 2 from Class 1, all three psychological variables differentiated Class 3 from Class 1, and difficulties with emotion regulation and trauma rumination differentiated Class 3 from Class 2. This study demonstrates that most people respond resiliently to non-fatal traffic accident. Yet, approximately one in three victims experiences moderate to severe mental health symptoms. Increasing PTS coincided with similarly increasing grief, indicating that grief may be considered in interventions for victims of traffic accidents. Trauma rumination strongly predicted class membership and appears a critical treatment target to alleviate distress.