On multiline slot machines, ‘wins’ often amount to less than the spin wager, resulting in a monetary loss to the gambler. Nevertheless, these losses disguised as wins (LDWs) are accompanied by potentially reinforcing audiovisual feedback. A concern for gambling behaviour is whether or not players categorize LDWs as wins or losses, as miscategorization could effectively increase the reinforcement rate of these games. The purpose of this study was to evaluate whether novice gamblers psychologically miscategorize LDWs. Forty-seven novices (undergraduate students) played 200 spins on an actual slot machine with credits, then estimated how often they won. It was found that the more LDWs players were exposed to, the higher their win estimates. In a subsequent ‘think out loud’ playing session, the majority of novices also verbally miscategorized LDWs as wins. We conclude that LDWs could increase the reinforcement rate of these games, despite not increasing the payout to the gambler.