This study investigated what psychological and social factors predict ‘perceived nativelikeness’ in late second language (L2) learners of French (L1 Swedish) (N = 62) with a minimum length of residence (LOR) of 5 years in France. The included factors were: language aptitude (LLAMA), acculturation (VIA), personality (MPQ), target language engagement and social networks (number of relations in L2). LOR and Length of French studies were also included as extraneous variables. Multiple linear regression analyses showed that positive effects were found for LLAMA D (sound recognition), acculturation (VIA France and VIA Sweden), number of relations in L2 and LOR. A negative effect was found for the personality variable Social initiative. The strongest effects were found for LLAMA D, Social initiative and LOR. All variables together explained 25% (adjusted R²) of the variance in the sample, which represents medium-sized effects in relation to other studies on individual factors. In sum, these findings confirm results from earlier studies on the importance of language aptitude and acculturation in late L2 acquisition. They also add evidence of the importance of personality, social networks, and LOR. On a more general note psychological and social factors combine to explain different outcomes in adult L2 acquisition, although the effects of psychological variables are deemed somewhat stronger.