Workers made their voices heard in 2023.

Between Jan. 1 and Nov. 30, there were 393 strikes in the U.S. involving more than 500,000 workers, according to Johnnie Kallas, a Ph.D. candidate at Cornell University's School of Industrial and Labor Relations and director of the university's Labor Action Tracker. This year saw more work stoppages involving 1,000 or more workers than any year since 2013, according to the Bureau of Labor Statistics.

And they made significant gains. In the first quarter of 2023 alone, union-represented workers saw an average 7% wage hike in the first year of their contracts, according to Bloomberg Law. That's the biggest wage hike in a single quarter since 2007.

"I'm pleasantly surprised and really impressed with the gains that labor has made," says Jason Resnikoff, assistant professor of contemporary history at the University of Groningen in the Netherlands. He adds that, "a bold labor movement has a lot to win."

Here's a roundup of a few unions' gains, why experts think they were so successful and what it could mean for other workers down the line.

Actors, autoworkers and health workers went on strike

Among some of the unions on strike this year were the following:

• WGA: After failed negotiationsopposite the Alliance of Motion Picture and Television producers, which represents studios like Universal and streamers like Netflix, Hollywood writers of the Writers Guild of America held a 148-day strike beginning in May. Issues at stake included staffing and residuals in the era of streaming and the future of writing with AI. The WGA got a 5% wage hike in the first year; minimum staffing levels on various shows; a new bonus for hit shows and movies on streaming; and restrictions around AI use.

• SAG-AFTRA: TV and film actors in the Screen Actors Guild-American Federation of Television and Radio Artists, too, reached a stalemate with AMPTP, beginning a 118-day strike in July. Issues included wages, residuals in the age of streaming and AI. They got a 7% wage hike in their first year; a new bonus structure for hit streaming shows and movies; and new protections around AI use such as consent and compensation in various scenarios.

• UAW: Auto workers at the United Auto Workers held a 46-day strike beginning in September after negotiations failed opposite automakers Ford, General Motors and Stellantis. Issues included pay, wage tiers and the future of work in the world of electric vehicles. The UAW got a minimum 33% wage increase over the course of the agreement, faster progression to top-paying gigs and inclusion of electric vehicle and battery jobs under the union's jurisdiction.

• Kaiser Permanente: Health-care workers at the Coalition of Kaiser Permanente Unions held a three-day strike in October after unsuccessful talks opposite Kaiser Permanente facilities regarding pay and staffing shortages since the pandemic. They got a 6% wage hike in the first year of their contracts and new initiatives to address staffing.

Other workers on strike this year included Alaskan fishermen, public school educators in Massachusetts and hotel workers in California.

Previous years' fights 'created a lot of momentum'

Worker fights did not happen in a vacuum, say experts. They were part of a larger wave of efforts building up over the last several years.

In 2020, for example, unions were able to bargain for PPE and extra pay for frontline workers. "I think the pandemic really showcased the power of unions," says Margaret Poydock, senior policy analyst at the Economic Policy Institute.

Workers also made history organizing in various industries. Amazon workers in Staten Island, New York, came together to create the first ever Amazon Labor Union in 2021. The same year saw workers at Starbucks organize for the first time at a store in Buffalo, New York.

"Nothing is more motivating than success," says Erica Smiley, executive director of worker advocate nonprofit Jobs With Justice. "It's created a lot of momentum in our movement."

'Almost a million workers were going to be in negotiations'

Another motivator to strike was the state of the labor market.

The unemployment rate remains low, currently 3.7%, according to BLS. When that happens there are fewer workers vying for the same jobs, giving them the power to move around and find better offers.

"It gets them into a position of relative security" in terms of job options, says Resnikoff. "It makes it much easier for them to go on strike."

Plus, many union contracts were up. Union contracts often last three to four years, when employers and workers must sit down to renegotiate the terms of employment.

"Almost a million workers were going to be in negotiations between the contract at UPS, the contract with the big three auto firms and then many others," says Smiley. "So that was already going to be an inflection point."

'Nothing succeeds like success'

Experts agree the momentum is not likely to stop as more unionized workers enter contract negotiations opposite employers in the coming years.

"Nothing succeeds like success," says Resnikoff about this year's wins, adding that "working people are seeing that it's possible."

And while unionized workers make up just 10% of workers in the U.S., according to BLS, other members of the workforce could end up benefitting from their 2023 gains as well.

In a competitive labor market where workers have more power to look for the best offer around, "union standards become standard even in non-union" workplaces, says Resnikoff. To attract talent, employers must match the best offers in the marketplace.

There's proof that that trickle down effect has already begun to take place. "Shortly after UAW reached agreements with the big three," says Poydock about the union's negotiations, "Toyota raised wages for their non-union workers." Tesla is planning to raise wages for some of its workers as well.

Disclosure: Universal parent company NBCUniversal is also the parent company of NBC and CNBC.

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