The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM‐5; American Psychiatric Association [APA], 2013) modified the diagnostic criteria for posttraumatic stress disorder (PTSD), including expanding the scope of dysfunctional, posttrauma changes in belief (symptoms D2—persistent negative beliefs and expectations about oneself or the world, and D3—persistent distorted blame of self or others for the cause or consequences of the traumatic event). D2 and D3 were investigated using a national sample of U.S. adults (N = 2,498) recruited from an online panel. The prevalence of D2 and D3 was substantially higher among those with lifetime PTSD than among trauma‐exposed individuals without lifetime PTSD (D2: 74.6% vs 23.9%; D3: 80.6% vs 35.7%). In multivariate analyses, the strongest associates of D2 were interpersonal assault (OR = 2.39), witnessing interpersonal assault (OR = 1.63), gender (female, OR = 2.11), and number of reported traumatic events (OR = 1.88). The strongest correlates of D3 were interpersonal assault (OR = 3.08), witnessing interpersonal assault (OR = 1.57), gender (female, OR = 2.30), and number of reported traumatic events (OR = 1.91). The findings suggested the expanded cognitive symptoms in the DSM‐5 diagnostic criteria better capture the cognitive complexity of PTSD than those of the DSM‐IV.