Section 7 of the National Labor Relations Act, passed in 1935, is the governing text.
It is short, and most people have never read it.
29 U.S.C. §157
"Employees shall have the right to self-organization, to form, join, or assist labor
organizations, to bargain collectively through representatives of their own choosing,
and to engage in other concerted activities for the purpose of collective bargaining
or other mutual aid or protection."
National Labor Relations Act, Section 7. Public law.
Protected concerted activity
You do not need a union to be protected
The phrase "other concerted activities" covers two or more employees acting
together about pay, hours or working conditions, whether or not a union
exists or is ever formed.
Discussing your wages with a colleague is protected concerted activity. An employer
policy forbidding employees from discussing pay with each other is generally unlawful
under the NLRA.
Coverage is not universal. The NLRA excludes agricultural workers,
domestic workers, independent contractors and supervisors. Public-sector workers are
covered by separate federal or state laws instead.
NLRB: Employee rights ↗
The election process
How a union is actually formed
Workers file a petition with the National Labor Relations Board, an independent
federal agency, supported by signatures from at least 30% of the proposed
bargaining unit. The NLRB then conducts a secret-ballot election. A simple
majority of votes cast wins.
In FY2025, 2,100 election petitions were filed. Unions won
81.9% of representation elections. Win rates first passed 70% in 2023
for the first time in fifteen years; before the 2010s they averaged under 60%.
NLRB: How elections work ↗
Bureau of Labor Statistics
The measured difference in pay
In 2025, full-time union members had median usual weekly earnings of
$1,404. Non-union workers had $1,174, or 84% of union
member earnings.
A difference of $230 per week, or roughly $11,960 a year at the median. BLS notes the
comparison does not control for occupation, industry, firm size or region.
Over the same period the private-sector union membership rate
fell 10.9 percentage points between 1983 and 2024.
BLS: Union Members Summary ↗
Gallup, August 2025
Public opinion, including the part that complicates the story
68% of US adults approve of labor unions, the fifth straight year
in the 67–71% range, a level last seen in the early 1960s. The record high was 75% in
1953; the low was 48% in 2009.
The party split, published in full: 90% of Democrats, 69% of independents and
41% of Republicans approve. Approval is higher among younger adults: 72% of
those aged 18–34 against 64% of those 55 and over.
Gallup is a non-partisan polling organization. The full breakdown is shown here rather
than the single headline number, because the headline alone would misrepresent it.