Which clinical measures of walking performance best predict free-living physical activity in community-dwelling people with stroke? Design: Cross-sectional observational study. Participants: 42 community-dwelling stroke survivors. Outcome measures: Predictors were four clinical measures of walking performance (speed, automaticity, capacity, and stairs ability). The outcome of interest was free-living physical activity, measured as frequency (activity counts) and duration (time on feet), collected using an activity monitor called the Intelligent Device for Energy Expenditure and Physical Activity. Results: Time on feet was predicted by stairs ability alone (B 166, 95% CI 55 to 278) which accounted for 48% of the variance. Activity counts were also predicted by stairs ability alone (B 6486, 95% CI 2922 to 10 050) which accounted for 58% of the variance. Conclusion: The best predictor of free-living physical activity in community-dwelling people with stroke was stairs ability.