California’s construction sector is experiencing a historic shift, as union membership falls to its lowest level in over a decade, reflecting broader changes in workforce dynamics and contractor preferences across the state.

According to data compiled from UnionStats.com, California counted 129,800 unionized construction workers in 2023, marking the lowest total since 2014. That figure is down 21% from just a year ago, and a striking 29% drop from 2019, the final pre-pandemic year.

The decline underscores a growing trend: organized labor’s influence in the building trades is shrinking, while non-union labor continues to rise across job sites statewide.

“Union membership in the building trades is down 21% in a year and off 29% from 2019, the year before the pandemic upended the economy.”

In contrast, non-union construction employment hit a record 907,200 workers in 2024, representing an 11% increase over the previous year and a 13% increase since 2019. The shift is partly fueled by general contractors and developers actively steering projects outside the purview of organized labor.

“Construction bosses have worked hard to keep as many projects as possible outside organized labor’s reach.”

The result? A dramatic drop in union density. Unions now represent only 12.5% of California’s total construction workforce — the lowest share ever recorded. That’s a significant dip from 17% in 2023, 19% in 2019, and well below the 21% average since 1983, when unions accounted for 39% of construction employment statewide.

“The shift in employment patterns means unions controlled 12.5% of all California construction workers last year, the smallest slice on record.”

The decline is also reflected in the overall composition of California’s unionized workforce. In 2024, only 5.5% of the state’s 2.2 million union members worked in construction, a noticeable drop from 6.6% in 2023, 7.3% in 2019, and the 6.4% historical average.

“And construction is also losing its share of California’s organized labor. Just 5.5% of the 2.2 million unionized workers statewide in 2024 were in the building trades.”

Union representation across all industries in California also hit a significant milestone: an 18-year low of 14% statewide.

“By the way, union membership in all California industries hit an 18-year low in 2024 at 14%.”

Regional Breakdown: Where Union Membership Still Holds — or Doesn’t

While statewide numbers paint a bleak picture for union strength in construction, some regional differences persist.

According to UnionStats data broken down by metro area, Los Angeles and Orange counties reported the highest number of unionized construction workers at 38,300, equaling 11% of the regional construction workforce.

Here’s how other regions compare:

• Inland Empire: 18,800 members (12%)
• San Diego: 15,600 members (17%)
• Stockton: 12,000 members (28%)
• San Francisco: 7,300 members (8%)
• Fresno: 5,200 members (32%)
• Modesto: 4,600 members (16%)
• San Luis Obispo: 3,700 members (52%)
• San Jose: 3,400 members (8%)
• Sacramento: 2,900 members (5%)
• Santa Rosa: 2,800 members (29%)
• Vallejo: 2,700 members (51%)
• Redding: 2,000 members (26%)
• Hanford: 1,700 members (57%)
• Chico: 1,600 members (20%)
• Visalia: 1,500 members (15%)
• Santa Maria: 1,400 members (5%)
• Santa Cruz: 1,600 members (22%)

Notably, no union members were recorded in Bakersfield, Salinas, or Ventura County.

As union influence continues to erode in one of the nation’s largest construction markets, the long-term implications could impact wage levels, job site standards, and training pipelines — all of which have traditionally been bolstered by organized labor. For now, however, the numbers point to a clear and accelerating trend: non-union labor is dominating California construction.

Jonathan Lansner is a business columnist for the Southern California News Group. He can be reached at jlansner@scng.com.

Originally reported by Jonathan Lansner in The Mercury News.