Background: Patients with Borderline Personality Disorder (BPD) are characterized by impoverished self-regulatory mechanisms and self-image distortions. An intriguing question is to what extent BPD individuals develop accurate perceptions of their self-regulatory everyday functioning. Here, we tackle this issue evaluating their metacognitive abilities.

Methods: One hundred and forty-four participants were enrolled in the study and divided into a BPD group and a healthy Control group, with each consisting of 36 participants paired with their corresponding close relatives. We compared self-report evaluations of the participants’ self-regulatory processes in daily-life activities and personality traits with external perceptions by close relatives, as a measure of metacognition. The ratings from participants and their informants were compared using an ANCOVA profile analysis.

Results: Self-report results showed poor self-regulation ability in the daily environment as well as extreme scores in personality-traits in the BPD group in comparison with healthy participants. Further, in the BPD group we found a clear discrepancy between the information provided by patients and their close relatives regarding the processes involved in self-regulation of daily-life activities (but not for personality traits). This discrepancy was related to their clinical status and was not observed in the healthy control group.

Limitations: Analysis was based on self-report data, focusing on the difference with informants reports only. Conclusions about the direction of a possible bias on participants’ self-perception are limited.

Conclusions: Metacognitive deficits might play a key mediating role between the altered cognitive processes responsible for self-regulation and cognitive control and the daily-life consequences in BPD.