The current research study made use of daily diaries and personality assessment to examine academic procrastination behaviour in the everyday lives of university students. Undergraduate students (n = 84) completed self-report measures on trait affect intensity, distress tolerance and emotion regulation difficulties before engaging in ten days of daily diaries. Multilevel regression analyses were used to examine whether within-person variations in the intensity of experienced negative moods and temptations predicted levels of self-reported procrastination behaviour, and whether these relations were moderated by individual differences in affect-related personality traits. As hypothesized, at the day-level of analysis, both the extent of negative affect and the strength of experienced temptations positively predicted levels of academic procrastination behaviour. Contrary to what was hypothesized, none of the affect-related personality traits directly or indirectly predicted procrastination behaviour, except for trait levels of emotion regulation difficulties which positively predicted average levels of daily procrastination behaviour.