Justification thinking (using excuses to “allow” giving into temptation) has been identified as a potential link between negative affect and self-control failure. We hypothesised that negative affect would prompt greater justification thinking, specifically deservingness thinking (i.e. “I deserve a treat”), and tested this for both inhibitory (temptation is to approach reward; self-control is to inhibit) and initiatory (temptation is to refrain from action, self-control is to initiate action) hypothetical self-control dilemmas. We found that only for inhibitory self-control (Study 1; N (...) = 105) but not initiatory (Study 2; N = 116), negative affect resulted in greater deservingness thinking compared to neutral affect. We also hypothesised that negative mood coupled with justification would prompt greater likelihood of imagined self-control failure. We found that for inhibitory self-control (Study 3; N = 569), participants in negative affect (vs. neutral) and justification (vs. no justification) conditions were independently more likely to report they would fail at self-control. For initiatory self-control (Study 4; N = 321), we found an effect of negative affect on hypothetical self-control failure but no effect of justification. Overall, these studies confirm the role of negative affect in self-control processes and highlight differences between inhibitory and initiatory self-control situations. (shrink)