Walkable communities are healthier communities, due to the physical activity of residents. Because a community’s built form has a strong influence over its walkability, many planners and public officials hope to improve walkability through zoning and infrastructure changes. However, communities that differ in factors such as geography and climate can require different solutions when planning for increased walkability. Most walkability studies in planning literature use temperate zones in the West and Northeast of the U.S. to determine which built environment factors promote higher rates of walking activity. The objective of this study was to identify variables that influence walkability in a sub-tropical climate. Four communities in South Florida were selected as case studies: two traditional neighborhoods with high Walk Scores and two modern neighborhoods with low Walk Scores. GIS spatial analysis was conducted through four perspectives: land use, built environment, transportation infrastructure, and urban tree canopy. Land use mix, building density, short block lengths in grid-like networks, and transit access were found to have the greatest effects on walkability in South Florida. These variables help reduce the walking distance between destinations, possibly mitigating the heat’s effect on pedestrian thermal comfort. While urban tree canopy and the presence of shade trees was theorized to increase walkability, no association was found. Research has applicability in other sub-tropical/tropical communities that are affected by sprawl and seek to improve walkability.