Golden SD, Baggett CD, Kuo TM, et al. - Since there are no estimates of national trends in tobacco retailer numbers and store type over time without a national tobacco retailer licensing system in the US, researchers sought to develop a protocol to identify likely tobacco retailers across the US between 2000-2017 utilizing industry codes and retailer names in the annual National Establishment Time Series database, as well as to calculate annual counts of tobacco retailers in seven store type categories, and annual numbers of tobacco retailers that opened and closed. The authors estimate that there were 317,492 tobacco product retailers in 2000; the number grew to 412,536 in 2009 before declining to 356,074 in 2017, for a net 12% increase overall. Tobacco retailer availability increased in the US during two decades when smoking declined. The economic climate, corporate and public policies, and new tobacco products may all influence trends in tobacco retailer availability. Retailer trend information may be useful for forecasting or evaluating potential policy impacts for state and local jurisdictions considering tobacco retailer policies.