This study explores the automobility behavior of millennials (those born between 1980 and 2000) and older adults (65 years and older) and the factors that influence their automobility behavior using cross-sectional data from Hamilton, Ontario. This study focuses specifically on how automobility behavior of millennials and older adults is shaped by their socio-demographic characteristics, living arrangements, attitudes, and preferences toward transportation modes and residential location characteristics. Results from the binomial and ordinal logistic regressions suggest that depending on whether a millennial or older adult lives alone, with a partner, or in an apartment, their automobility behavior differs. The study also finds that positive attitudes and preferences toward sustainable travel behavior make both generations less auto-oriented, especially millennials. Regarding preferred residential location characteristics, compared to older adults, millennials’ preference toward off-street parking in their residential neighborhood is likely to influence their automobile use. Compared to older adults, living arrangements, attitudes, and preferences influence, to a greater extent, millennials’ attributes of automobility. Further, the study also suggests that living arrangements, attitudes, and preferences can differ among millennials and older adults. Consequently, the impact on each of the attributes of automobility behavior will differ.