24 Hour Fitness
| Company type | Private |
|---|---|
| Industry | Fitness |
| Founded | 1 January 1983 in San Leandro, California, United States |
| Founder | Mark S. Mastrov |
| Headquarters | Carlsbad , United States |
Area served | United States (California, Colorado, Hawaii, New Jersey, New York, Nevada, Oregon, Texas, Washington) |
Key people | Karl Sanft (CEO) |
| Products | Fitness centers |
Number of employees | 7500+ (2025) |
| Website | 24hourfitness |
24 Hour Fitness is a privately owned chain of fitness centers based in Carlsbad, California. It stands as the second highest-grossing fitness chain in the United States, trailing only LA Fitness, and ranks fourth in terms of the total number of clubs, operating 249 gyms across nine states. Established by entrepreneur Mark S. Mastrov, the company changed hands in 2005 when Forstmann Little & Co acquired it, and later was sold to AEA Investors along with the Ontario Teachers' Pension Plan in 2014.
The financial strain caused by the COVID-19 pandemic led to a bankruptcy filing in June 2020 and the shutdown of more than 130 locations. By December 2020, 24 Hour Fitness reemerged from bankruptcy under new ownership groups including Sculptor Capital Investments LLC, Monarch Alternative Capital LP, and Cyrus Capital Partners LP. During this restructuring period, CEO Karl Sanft has been instrumental in steering the company’s strategic direction.
Founding and initial development
Originally launched as 24 Hour Nautilus in 1983 in San Leandro, California, Mark Mastrov converted a local gym into a round-the-clock facility after acquiring it. In 1996, the company merged with Family Fitness, which was founded by Ray Wilson in Carlsbad in 1977, leading to a unified brand under "24 Hour Fitness."
2004–2008: Olympic involvement and media partnerships
Between 2004 and 2008, 24 Hour Fitness acted as a sponsor for U.S. Olympic teams by offering memberships to athletes and funding enhancements at Olympic Training Centers located in Colorado Springs, Lake Placid, and Chula Vista. Additionally, the company collaborated with NBC to produce the reality television series The Biggest Loser, which premiered in late 2004 and featured contestants competing for monetary rewards through weight loss challenges.
In 2005, 24 Hour Fitness became a co-sponsor of the Discovery Channel Pro Cycling Team alongside cyclist Lance Armstrong and introduced its inaugural Lance Armstrong Signature Club. However, the partnership ended in 2012 following Armstrong’s doping revelations.
2009–present: Ownership changes and international operations
At one point, 24 Hour Fitness operated approximately 15 gyms across Singapore and China through its fully owned subsidiary California Fitness (CalFit), with facilities in Hong Kong, Beijing, and Shanghai. Its European locations were closed during the early 2000s. In 2012, CalFit was sold to Hong Kong’s Ansa Group, allowing 24 Hour Fitness to concentrate exclusively on its U.S. operations.
California Fitness also spawned California Wow Xperience (CalWowX), which maintained reciprocal membership agreements with both California Fitness and 24 Hour Fitness. CalWowX managed gyms located in Bangkok, Chiang Mai, and Pattaya, including clubs exclusively for women.
In August 2012, the owner placed the chain—comprising 416 locations—on the market with an estimated valuation near $2 billion. Despite six months of interest from potential buyers, offers did not meet expectations, prompting the board to withdraw it from sale in January 2013.
By May 2014, Forstmann Little & Co. divested 24 Hour Fitness Worldwide Inc. for $1.85 billion to a consortium led by AEA Investors LP and Ontario Teachers' Pension Plan.
During the COVID-19 crisis in April 2020, facing widespread gym closures, the company considered filing for Chapter 11 bankruptcy protection. The filing was finalized in June 2020 alongside announcements of closing over 130 facilities. By December of that year, 24 Hour Fitness had successfully emerged from bankruptcy proceedings, marking a significant recovery in its financial standing.
Operations
By May 2025, 24 Hour Fitness managed a network of 249 fitness centers spread across nine states: California, Colorado, Hawaii, New Jersey, New York, Nevada, Oregon, Texas, and Washington. The company employs more than 7,500 individuals. Its main rivals within the United States fitness industry include Anytime Fitness, Gold's Gym, and LA Fitness.
In the early months of 2025, Onelife Fitness expanded its presence by acquiring two clubs located in Fairfax and Falls Church, Virginia. Meanwhile, Crunch Fitness grew its footprint by purchasing nine facilities throughout Florida, including locations in Apopka, Doral, Homestead, Kirkman, Lake Mary, Miami Gardens, Orlando Park, Plantation, and Winter Park.
Criticisms
On July 31, 2007, 24 Hour Fitness resolved a class-action lawsuit involving approximately 1.8 million members who experienced unauthorized automatic payment withdrawals after cancelling their memberships. In the case of McCardle vs 24 Hour Fitness USA, Inc., the Alameda County Court ruled against the company for not upholding the "All Club" membership benefits at rebranded venues without charging extra fees.
In July 2010, a group of six former employees initiated another class-action lawsuit accusing the company of racial and gender discrimination related to promotional opportunities. The plaintiffs included women and minority individuals who contested the organization's internal advancement policies.
Ratings and reviews
As of May 31, 2024, the Better Business Bureau (BBB) had recorded 650 complaints against 24 Hour Fitness over a three-year period, with 291 complaints filed in the preceding year alone. The organization holds a C- rating from the BBB, indicating persistent customer service issues that could affect its reputation and potential for growth in the market.