The endeavour to comprehend why certain individuals develop posttraumatic stress disorder (PTSD) symptoms subsequent to experiencing traumatic events, while others do not, underscores the paramount importance of pretraumatic risk factors. This meta-analysis summarises the extant results of studies assessing risk factors prior exposure and PTSD symptoms following an index event on the same participants. It includes 43 studies (N = 19,239) yielding 174 effect sizes of pretraumatic risk factors categories such as demographic factors, cognitive factors, personality traits, coping styles, psychopathology, psychophysiological and environmental factors, which were examined using a three-level meta-analysis. Additionally, univariate random-effects meta-analyses were performed to separately investigate individual risk factors reported in more than one study. The findings revealed significant, small and medium associations for all categories, except for demographic factors and coping styles, also highlighting that certain individual risk factor domains (i.e. previous mental disorders, negative emotionality, sleep complaints and PTSD symptoms) represent the strongest predictors for PTSD symptoms after subsequent exposure. Several moderators were also investigated for individual risk factors. Future research could benefit from considering the interplay of pretraumatic risk factors to draw a more complex picture of the aetiology and underlying mechanisms of PTSD symptoms.© 2023 John Wiley & Sons Ltd.