A cue that signals reward can capture attention and elicit approach behaviors in people and animals. The current study examined whether attentional capture by reward-related cues is associated with severity of addiction-related and obsessive-compulsive behaviors. Participants were recruited via Mechanical Turk and included 143 adults [mean age 34 years (SD = 8.5), 43% female] who had endorsed at least one addiction-related or obsessive-compulsive behavior in the past month. All assessment components were delivered via the internet, and included questionnaires to assess severity of compulsivity-related problems across addiction-related and obsessive-compulsive behaviors, as well as a visual search task to measure reward-related attentional capture. Reward-related attentional capture was associated with severity of compulsivity, transdiagnostically. These findings have implications for understanding the mechanisms that underlie compulsive behaviors and suggest that reward-related attentional capture is a promising transdiagnostic cognitive risk marker for compulsivity.