Minimum Wage Policy: What the Research Shows About Effects on Workers and Businesses

The minimum wage has been one of the most studied policies in labor economics, and the research findings have evolved substantially over the past three decades. Early economic theory predicted that minimum wage increases would reduce employment by raising the cost of labor above its market-clearing price. A landmark 1994 study by economists David Card and Alan Krueger challenged this prediction empirically, finding no negative employment effects from a minimum wage increase in New Jersey. The Card-Krueger study sparked a research debate that has continued for thirty years and has produced a considerably more nuanced picture than the simple theory suggests. Federal minimum wage is currently 7.25 dollars per hour, a level that has not changed since 2009 and that, in inflation-adjusted terms, is lower than it was in the late 1960s. Many states and cities have adopted minimum wages substantially above the federal floor, with some reaching 15 dollars or more. This variation across jurisdictions has created natural experiments that researchers have used to study minimum wage effects with increasingly sophisticated methods. The employment effects of moderate minimum wage increases are small and often statistically indistinguishable from zero in the best studies. Research using difference-in-differences methods comparing counties or states that raised their minimum wages to adjacent counties or states that did not has generally found limited negative employment effects, particularly in low-wage sectors. Higher-wage increases and those implemented in weak labor markets show somewhat more evidence of negative effects, but even these are typically modest in magnitude. The distributional effects of minimum wage increases matter for evaluating their policy implications. Minimum wage workers are disproportionately lower-income, though not exclusively: many are secondary earners in middle-income families. Research on the distributional effects of minimum wage increases generally shows that the earnings gains are concentrated among lower-income workers and translate into meaningful improvements in living standards. Some research shows small increases in poverty rates among families just above the poverty line who may lose some employment, complicating simple poverty reduction claims, but the preponderance of evidence finds minimum wage increases to be modestly poverty-reducing. Business effects vary by industry, firm size, and local market conditions. Industries with high shares of minimum wage workers, including restaurants, retail, and home care, face more significant cost increases than industries with few minimum wage workers. How businesses respond to these costs varies. Research documents a mix of responses including reduced hours, reduced employment, reduced benefits, reduced turnover, increased automation in some settings, modest price increases, and reduced profit margins. No single adjustment mechanism dominates, and the relative importance of each varies across contexts. Restaurant industry research is particularly developed because restaurants employ large shares of minimum wage workers. Studies comparing restaurant employment in counties that border each other but are in different states with different minimum wages find small to negligible negative effects on restaurant employment from moderate minimum wage increases. Research on fast food specifically, including the Seattle Minimum Wage Study that generated controversy in its initial reports but produced more nuanced findings in longer-term analysis, suggests that effects on employment hours are small and that earnings gains are meaningful for affected workers. Effects on small businesses differ from effects on large businesses, and this distinction matters for policy design. Small businesses with thin margins and limited capacity to adjust on multiple dimensions may face more significant challenges from minimum wage increases than large businesses that can more easily absorb costs, automate, or adjust benefit structures. Small business exemptions and phase-in schedules are policy tools used to address differential impact. The comparison to a living wage, the income needed to cover basic expenses in a given labor market, is relevant context. The federal minimum wage is well below living wage estimates in virtually all parts of the United States. Even state and city minimums that have risen substantially often fall short of living wages in high-cost urban areas. This context shapes the stakes of the policy debate: minimum wage levels that are far below living wages leave many full-time workers in poverty despite working, while higher minimum wages bring their own adjustment dynamics. The research consensus as of the mid-2020s is that moderate minimum wage increases have small negative employment effects, generate meaningful earnings gains for low-wage workers, reduce poverty modestly, and do not trigger the large disemployment effects predicted by simple economic theory. Larger increases and those implemented quickly in weak labor markets carry more uncertain effects. These findings support a policy position that minimum wage increases are a legitimate tool for reducing earnings inequality, while acknowledging that wage floors alone cannot address the scale of income inequality in the United States.