Spillover Effects from Voluntary Employer Minimum Wages

Abstract

Low unionization rates, a falling real federal minimum wage, and prevalent non-competes characterize low-wage jobs in the United States and contribute to growing inequality. In recent years, a number of private employers have opted to institute or raise company-wide minimum wages for their employees, sometimes in response to public pressure. To what extent do wage-setting changes at major employers spill over to other employers, and what are the labor market effects of these policies? In this paper, we study recent minimum wages by Amazon, Walmart, Target, and Costco using data from millions of online job ads and employee surveys. We document that these policies induced wage increases at low-wage jobs at other employers. In the case of Amazon, which instituted a $15 minimum wage in October 2018, our estimates imply that a 10% increase in Amazon's advertised hourly wages led to an average increase of 2.6% among other employers in the same commuting zone. Using the CPS, we estimate wage increases in exposed jobs in line with our magnitudes from employee surveys and find that major employer minimum wage policies led to small but precisely estimated declines in employment, with employment elasticities ranging from -.04 to -.13.