<p>Impaired self-control is linked to maladaptive behavior and psychopathology and may be shaped by transdiagnostic factors such as impulsivity and compulsivity. Both traits show associations with model-based control, which supports goal-directed behavior by representing long-term action consequences. To investigate how model-based control and personality traits relate to everyday self-control, we combined single-trial EEG data (modulation of the feedback-related negativity [FRN] and P3) from 236 participants during a two-step decision-making task with self-reported impulsivity (BIS-11) and compulsivity (OCI-R) and a seven-day ecological momentary assessment of daily-life self-control. Mixed-effects models revealed that desire enactment was more likely when desires were stronger and perceived conflicts weaker. The effect of model-based control varied with impulsivity and compulsivity: In individuals low in compulsivity, stronger modulations of the FRN, suggesting higher model-based control, were connected to fewer desire enactments, suggesting a protecting role of model-based control. This pattern reversed at high compulsivity levels, possibly due to greater conflict awareness but reduced behavioral regulation capacity. Impulsivity moderated compulsivity effects, such that model-based control consistently predicted reduced enactment at high impulsivity levels. These findings highlight how compulsivity and impulsivity shape the translation of cognitive control into everyday behavior and offer insights into mechanisms underlying self-control deficits.</p>