The primary objective of this research was to examine societal and intraindividual behavioural determinants of sleep-wake timings and social jetlag. Occupational demands and timings may influence bedtime and waketime. Behavioural factors could additionally influence sleep-wake timings via bedtime decisions. The impact of workday sleep-wake timings on social jetlag was explored in this research. The association between social jetlag and the temporal consideration and discounting of future consequences and dysfunctional beliefs about sleep were also explored. The evidence from the current research suggest that societal factors have a strong influence on social jetlag. Later workday sleep-wake timings during the pandemic resulted in a significant reduction in social jetlag. There was no evidence of an association between social jetlag, chronotype and intraindividual traits. Work-free day midsleep (chronotype) was a significant determinant of social jetlag. Social jetlag and chronotype demonstrated differential relationships with other societal and demographic factors. Differential relationships between social jetlag, chronotype and other key sleep parameters such as sleep quality and insomnia were also observed. Current research suggests social jetlag may be a distinct sleep phenomenon with strong associations with sleep-wake timings. Modifications to work schedules may be one option for reducing social jetlag. However, this was at the expense of late sleep-wake timings, and the long- term chronobiological implications of the changes observed during the pandemic are yet to be fully understood. Alternatively, a reduction in social jetlag may be feasible via phase advancing of late chronotypes. Social jetlag is ubiquitous in modern society and presents a significant public health concern. Current research identifies challenges to translation of circadian science into policies. Public education on sleep regularity and circadian misalignment could facilitate a discussion between scientists and the general public and may facilitate a chronobiologically sound solution to the widespread problem of social jetlag in modern society.