Mandatory home isolation caused by COVID-19 in professional contexts led to a situation that required work activities to be converted into a remote modality. The literature on this topic is very recent, given the pandemic and the uncertainty of virtual and face-to-face work modalities. This study aimed to examine the effects of adults’ prolonged exposure to screens on sleep quality, the type of devices used according to age and gender, periods of access to such devices and the impact on performance in the context of telework due to COVID-19. Specifically, the study analyzed the differences in the use of devices and in the time spent using them during and after teleworking between genders and age groups. A total of 127 Portuguese participants answered the Pittsburgh Sleep Quality Index and a questionnaire that we specifically developed to characterize teleworking habits. The results showed differences between men and women regarding the use of devices and its impact on sleep quality, as well as differences in terms of age. These results are discussed in terms of how the current work context may affect performance, sleep, gender differences and the adverse effects of exposure to screens during and after work hours.