Stuttering is a disorder of speech fluency that is not well understood, in part due to its variable nature. Although a number of factors have been found to contribute to this variability, previous research has often been retrospective or experimental. In this study, forty-one college students completed a survey three times a day for at least two weeks. Each participant evaluated their experiences regarding their own speech fluency, affective state, and willingness to approach. It was expected that affective state would be associated with speech fluency as well as willingness to approach. The main finding of the study was that dimensions of affect (i.e., arousal and mood) were significantly associated with speech fluency, particularly in the morning compared to the afternoon or evening. Results are interpreted to suggest that the positive relation between speech fluency and affect could be outcomes of a common physiological state, a finding that could have important implications for fluency disorders such as stuttering.