The appearance of the COVID-19 virus in Europe, at the beginning of 2020, brought many challenges and changes to society. These changes affected the behavior, desires, and needs of passengers in vehicles. The change in passenger behavior has contributed to the more difficult organization of passenger transport and traffic management. For these reasons, in the countries of South-East Europe (Serbia, Montenegro, Slovenia, Bosnia and Herzegovina, Greece, the Republic of Northern Macedonia and Croatia), this survey was conducted in order to examine which demographic characteristics of respondents (age, gender, residence, education, and health) influence choice of transport, with the aim to optimize the transport system in times of crisis in this region. 786 respondents participated in the research. The results showed that the acceptability of vehicle occupancy most often differs with respect to age, education, and health conditions of the respondents. The obtained results will greatly help the organizers of public transport and the transport system in the region, since based on these results they can have an insight into the demographic factors that influence the choice of transport mode during a crisis.