According to the Bureau of Labor Statistics, in 2023, the median weekly earnings for full-time union members were $1,263, compared to $1,090 for nonunion workers. This is a slight increase from 2022, when 11.2% of workers were represented by a union, which is similar to 2023.  

HOW DO UNIONS REDUCE INEQUALITY?

There are at least three major ways, described in previous research by economists and other social scientists, in which unions tend to narrow income inequalities:

First, unions boost the incomes of workers in low-wage occupations relative to workers in other occupations. Workers in lower-wage occupations are more likely to become union members—and to get increased wages and employer-provided benefits—than workers in already higher-income occupations.

Second, unions tend to boost the incomes of their lowest-wage members to a greater degree than the incomes of higher-wage members. This reduces the income gaps (produces “wage compression”) among unionized workers.

Third, unions tend to pull down the incomes of those at the top. While employers try to pass on cost increases (such as those resulting from higher wages and benefits) to customers in the form of higher prices, they cannot normally do so fully. As a result, increases in worker compensation tend to “squeeze” profits, reducing the income inequalities between workers and employers.

But bargaining between workers and employers isn’t the whole story. In almost all high-income countries, taxes and transfers reduce the degree of income inequality to some degree—though in some countries much more than others.

Source: https://labornotes.org/blogs/2020/10/economics-brief-rise-income-inequality-united-states