Uber and similar rideshare services are rapidly dispersing in cities across the United States and beyond. Given the convenience and low cost, Uber has been characterized as a potential countermeasure for reducing the estimated 121 million episodes of drunk driving and the 10,000 resulting traffic fatalities that occur annually in the United States. We exploited differences in the timing of the deployment of Uber in US metropolitan counties from 2005 to 2014 to test the association between the availability of Uber’s rideshare services and total, drunk driving-related, and weekend- and holiday-specific traffic fatalities in the 100 most populated metropolitan areas in the United States using negative binomial and Poisson regression models. We found that the deployment of Uber services in a given metropolitan county had no association with the number of subsequent traffic fatalities, whether measured in aggregate or specific to drunk-driving fatalities or fatalities during weekends and holidays.