Previous research suggests that dog owners are slightly more physically active than those without dogs, but have only studied one household member, and it is unclear whether time spent dog walking replaces other physical activity (PA). A survey of 191 dog owning adults (DO), 455 non-dog owning adults (NDO), and 46 children, living in 385 households in West Cheshire UK, was conducted in July-August 2015. Objective (accelerometer) validation occurred on a subset (n = 28 adults). Survey PA outcomes were modelled using hierarchical logistic and linear multivariable regression modelling, accounting for clustering of participants in households. DO were far more likely than NDO to report walking for recreation (OR = 14.35, 95% CI = 5.77–35.79, P <0.001), and amongst recreational walkers walked for longer per week (RR = 1.39, 95% CI = 1.27–5.91, P <0.001). Other PA undertaken did not differ by dog ownership. The odds of DO meeting current physical activity guidelines of 150 mins per week were four times greater than for NDO (OR = 4.10, 95% CI = 2.05–8.19, P <0.001). Children with dogs reported more minutes of walking (P = 0.01) and free-time (unstructured) activity (P <0.01). Dog ownership is associated with more recreational walking and considerably greater odds of meeting PA guidelines. Policies regarding public spaces and housing should support dog ownership due to PA benefits. © 2019, The Author(s).