Objective: 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. Method: 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. Results: 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. Conclusions: 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.