The aim of this study was to identify latent classes of posttraumatic stress disorder (PTSD) symptoms in a community sample of sexual assault survivors whose assaults occurred varying lengths of time in the past and to explore patterns of transition between those latent classes over time. Latent class analysis was used to identify naturally occurring subgroups of PTSD symptoms in a sample of sexual assault survivors who completed two mailed surveys 1 year apart (N = 1,271). Latent transition analysis was then used to examine individuals' probabilities of transitioning into each latent class at Time 2 based on their latent class membership at Time 1. A four-class model emerged as the best fitting model at both Time 1 and Time 2. Classes demonstrated overall severity and symptom cluster severity differences. Transition into a lower severity class was more common than transition into a higher severity class, though escalation was demonstrated by 6-20% of participants in each latent class. The substantial heterogeneity in sexual assault survivors' PTSD symptoms highlights the variety of ways that posttraumatic stress may be experienced years after a sexual assault. Future research should explore factors that affect long-term symptoms, including cumulative lifetime trauma and social support. (PsycInfo Database Record (c) 2024 APA, all rights reserved).