I argue that property developers who want planning permission for major building projects should face a new “health test” imposed by local councils to see if their plans will promote healthier living in the area. Good developments can improve wellbeing and encourage healthier lifestyles. Badly-designed building can encourage over-crowding and reliance on cars for transport instead of walking or cycling. Overcrowding has been linked to the spread of diseases including COVID-19, while places with high rates of car use can have poor air quality and higher rates of obesity. If a development demonstrates health net gain, for example, the local authority can grant an accelerated planning permission, which would lead to huge cost savings and contribute positively to the viability of the proposal.