Commuting patterns and use of bus, cycling, and walking in small and medium-sized U.S. cities: an analysis of demographic influences

• Transit is scarce with over 70% of block groups lacking bus commuters in small and medium-sized cities. • Zero-vehicle households strongly predict bus use and correlate with very low-income areas. • Income effects vary by coverage with median income linked to bus share only in network-rich states. • Bus-served areas show higher walking and cycling, and bus commutes average 33 minutes versus 23 by car. • Policy focus is to close supply gaps, improve service quality, and upgrade pedestrian infrastructure in low-income areas. Using 2015–2019 American Community Survey block-group data, we study commuting by bus, cycling, and walking in small and medium-sized U.S. cities, where auto-centric urban form raises equity concerns. We center the analysis on supply as well as demand by asking whether service is present where vulnerable residents live. Three results stand out. First, scarcity is pervasive: more than 70 percent of block groups report no bus commuters, indicating widespread transit deserts. Lack of a household vehicle strongly predicts non-automobile commuting and is tightly correlated with the share of very low-income households. Second, relationships vary with network coverage. In both the bottom and top deciles of states ranked by the prevalence of blocks with any bus commuters the share of very low-income households is a positive and significant predictor of bus commuting. Median household income is not significant in pooled models but is positively associated with the bus commuter share in the top-decile OLS, while its effect in the corresponding logit is very small and negative for the probability of having any bus commuter. Third, we observe modal complementarity in descriptive comparisons and a sizable time penalty, with places that have bus commuters also showing higher walking and cycling shares. Bus commutes average 33 min versus 23 min by car, and 33 percent of bus commuters travel at least 45 min each way compared with 10 percent of drivers. Walking shares rise with median income. These patterns point to supply gaps as a binding constraint and to the need for investments that expand coverage and improve pedestrian infrastructure in lower-income neighborhoods.