The COVID-19 pandemic that erupted in early 2020 has affected the everyday life, the practices, and the perceptions of the global population significantly. The aim of this paper is to investigate the perceptions, experiences, and practices of the active population regarding everyday urban life (working conditions, mobility, urban space, etc.) in the context of the first wave of the pandemic, by focusing on people who live and work in Greek cities. The data were collected using a structured questionnaire addressed to an active population. The majority of respondents declared that their personal and family lives were affected by the lockdown, with significant effects on their professional life and economic activities. Stress and fear were two feelings that increased. As far as mobility was concerned, the majority of respondents were unwilling to change their commuting practices. Although most of our findings presented a homogenous distribution in our sample, some changes in perceptions, experiences, and practices were correlated with the gender, age, and family status of the respondents. The results of the analysis provide useful information to policy makers and show that it is necessary to radically rethink aspects of urban space and urban mobility, in relation to the multiple problems and dynamics of the active population.