In this research, we use location data gathered from mobile devices to measure the impact of OOH advertising. Our data come from a location data provider that collects granular, timestamped location data from millions of individual mobile devices. We identify the devices that are detected at a professional sports stadium during the time that a large healthcare provider began its sponsorship of the team. Combining the data from the CRM system of the healthcare provider with the data from the location data provider, we identify the households who are detected at the stadium during at least one of the team’s home games and distinguish these households from those who are not detected at the stadium during one of these games. Using a difference-in-differences analysis, coupled with coarsened exact matching (CEM; Iacus et al. 2012) to alleviate concerns of self-selection, enables us to determine the extent to which OOH advertising (in our empirical analysis, the sponsorship of the team)affects expenditures at the healthcare provider by comparing expenditures before the sponsorship activities and expenditures after the sponsorship concluded.