Background <p>Built environment metrics are widely used to assess walkability, but they often assume that conditions remain stable throughout the year. Under snow and ice conditions, accumulated and prolonged snowfall disrupts active behaviours and changes how people move through urban environments. Nevertheless, many built environment metrics do not fully consider these snow- and ice-related challenges.</p> Methods <p>A systematic search of Scopus, PubMed, Web of Science, and ScienceDirect identified peer-reviewed English-language studies reporting relationships between built environment metrics and active behaviour under snow and ice barriers. Searches combined terms related to snow and ice, built environment, and active and sedentary behaviour outcomes, with the final search on 31 July 2025. From 1,501 records, 14 studies met the inclusion criteria. Data on study characteristics, exposure and outcome measures, and key results were extracted and synthesised narratively due to heterogeneity in study designs and measures.</p> Results <p>The included studies were conducted primarily in Canada and Sweden, with others from China, Japan, Finland, and the United States. Walking was the most frequently investigated active behaviour outcome (50%), followed by total physical activity (29%) and cycling (21%). Most quantitative studies reported positive associations between built environment metrics and physical activities under snow and ice barriers, with fewer reporting null results. Qualitative studies consistently described supportive influences. Active transportation infrastructure (57%) and snow- and ice-specific adaptations (64%) were the most frequently examined metrics, both showing predominantly positive relationships with active behaviours.</p> Conclusions <p>Snow- and ice-specific adaptations and active transportation infrastructure appeared to be the urban design domains most consistently relevant to active behaviour under snow and ice conditions. Evidence for composite walkability measures and less frequently studied metrics, including land use mix, residential density, destination accessibility, public transportation accessibility, aesthetics, and public open space or greenspace access, remained limited. Objective, dynamic, and longitudinal snow-sensitive metrics are needed to assess how winter maintenance, sidewalk snow clearance, cycling infrastructure, covered pathways, and other interventions can reduce snow-related barriers to active behaviour and support year-round walkability.</p>