People with dementia want to live well, and there was a strong recommendation from the 2017 National Dementia Care Research Summit to include outcomes that measure wellbeing in care, services and supports for this population (Kolanowski et al., 2018). Well-being for people living with dementia has been conceptualized as the extent to which psychological needs for comfort, attachment, inclusion, occupation and identity are met (Kaufmann & Engel, 2016). In the general population, well-being is assessed by self-report or by observing states of emotionality, but the former approach is problematic when neurodegenerative diseases progress and verbal communication becomes difficult. For this reason investigators often infer states of well-being in late stage dementia by observing displays of affect (Lawton, Van Haitsma, & Klapper, 1996). Affect balance is a concept developed by Bradburn who hypothesized that well-being is a judgement made by people when comparing the relative frequency of experiencing positive affect versus negative affect over a given time period. The mere absence of negative affect