The study will cover 30 stations and examine travel behaviour, attitudes to sustainable modes of transport and demand for public transport links.
MVA's smarter travel directorate head Conrad Haigh, who will lead the study, maintained: "A travel plan has the potential to encourage travelling to a station by alternative vehicles to private cars."
He added: "This will help in managing the demand for car parking and improve access to the station, helping to expedite the growth in rail passenger numbers."
Southern is owned by transport companies Go-Ahead and Keolis. It runs services between London and the south coast.