These California-based companies specialize in facility management, encompassing a broad range of services from comprehensive security and janitorial work to advanced energy efficiency and mechanical contracting. The list includes large corporations like Allied Universal, which provides tailored security and facility services, and KBS - Kellermeyer Bergensons Services, LLC, focusing on janitorial and exterior maintenance. Also present are specialized firms such as Legence, an integrated provider of energy efficiency solutions, and ACCO Engineered Systems, a mechanical contractor for HVAC and plumbing.
A notable pattern among these companies is the diverse scope of their offerings, often integrating technology and sustainability. While many provide traditional facility services, others like PRIDE Industries combine business excellence with social impact by employing people with disabilities. Headquarters are distributed across Southern California cities such as Irvine, Oceanside, and Los Angeles, alongside Northern California hubs like San Jose and San Francisco.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
Allied Universalaus.com
Provides tailored security and facility services using smart technology, supporting diverse sectors with local leadership and community presence. |
104,797 | |||
| 2 |
KBS - Kellermeyer Bergensons Services, LLCkbs-services.com
Provides janitorial services, floor care, exterior maintenance, facility operations support, and hospitality staffing across North America to businesses for clean environments. |
5,743 | |||
| 3 |
Legencewearelegence.com
Integrated provider of energy efficiency and sustainability solutions for diverse industries, specializing in advisory, engineering, contracting, and maintenance services for high-performance facilities |
3,648 | |||
| 4 |
ACCO Engineered Systemsaccoes.com
A leading mechanical contractor offering design, installation, maintenance, and service of HVAC, refrigeration, plumbing, process piping, and building automation systems |
2,686 | |||
| 5 |
PRIDE Industriesprideindustries.com
Delivering business excellence with a positive social impact by providing career opportunities and training for people with disabilities and other barriers to employment |
2,195 | |||
| 6 |
Able Servicesabm.com
A company specializing in facility services, engineering, and technical services, focused on enhancing occupant experience and improving spaces through innovation and sustainability |
1,851 | |||
| 7 |
CoolSys - Refrigeration and HVAC Systemscoolsys.com
This company provides sustainable refrigeration, HVAC, energy, and engineering solutions for various sectors, covering the entire lifecycle of commercial systems |
1,675 | |||
| 8 |
Flagship Facility Services, Inc.flagshipinc.com
A facilities maintenance company providing janitorial, engineering, and maintenance services to industries across the US and Canada, focusing on customer experience |
1,528 | |||
| 9 |
All Starall-star.com
A privately owned firm specializing in aerospace support, facilities maintenance, military housing, logistics, construction, and fleet maintenance for military, government, and commercial contracts |
1,501 | |||
| 10 |
Blackstone Consulting, Inc.blackstone-consulting.com
A minority-owned company providing environmental, security, facilities maintenance, staffing, and food service management services to national and international clients since 1991 |
1,091 | |||
| 11 |
Kineticsexentec.net
A full-service process and mechanical contractor specializing in design and installation of systems for technology-driven markets, with global support and focus on safety and customer service |
1,014 | |||
| 12 |
SodexoMagicsodexomagic.com
A joint venture between Sodexo and Magic Johnson Enterprises providing innovative, flexible, and comprehensive service solutions in food, wellness, and quality of life |
789 | |||
| 13 |
EMCOR Services Mesa Energymesaenergy.com
This company provides HVAC, building automation, and retrofit services, delivering customized energy solutions for enhanced occupant comfort and lower operating costs |
685 | |||
| 14 |
Los Angeles County Internal Services Departmentisd.lacounty.gov
The company prioritizes speed, reliability, and value in its services or products |
648 | |||
Want more companies than this list?This page shows the largest ones only. Connect to Tamtam to see every company that matches, filter by size, industry or growth, and reach their decision-makers. | |||||
| 15 |
DTZ, a UGL companycushmanwakefield.com
Global leader in property services offering end-to-end solutions for occupiers and investors worldwide, including leasing, property management, capital markets, valuation, and project management |
609 | |||
| 16 |
Serviconservicon.com
Servicon provides flexible cleaning and maintenance solutions to various industries, focusing on creating healthy environments and embracing innovation in the industry |
515 | |||
| 17 |
Sciens Building Solutionssciensusa.com
Provider of fire protection, security, communications, and electrical solutions for various industries, dedicated to ensuring safety, protection, and business continuity |
508 | |||
| 18 |
Pacific Rim Mechanicalprmech.com
Full-service mechanical engineering and HVAC/plumbing contractor in Southern California, offering energy solutions, HVAC controls, and maintenance for various commercial and industrial facilities |
473 | |||
| 19 |
ArchKey Solutions/Sprig Electricarchkey.com
A leading specialty trade installation and facilities services company offering design, construction, and maintenance of electrical and technology systems nationwide |
390 | |||
| 20 |
Pegasuselevate.pegasusclean.com
Global leader in critical cleaning using advanced technology to create clean, healthy indoor environments for commercial and industrial facilities Recognized for growth and workplace excellence |
256 | |||
| 21 |
DMS Facility Servicesdmsfacilityservices.com
A people-oriented, environmentally responsible organization providing high-quality, cost-effective service solutions to businesses and communities, using sustainable products and procedures |
182 | |||
| 22 |
ENGIE Services North Americaengieservices.us
National energy company delivering integrated Energy Effective programs for education, government, commercial, and industrial clients, aiming to drive sustainable results and promote a low-carbon economy |
182 | |||
| 23 |
CarParkcarpark.com
An LA-based company specializing in parking facility management and transportation, dedicated to enhancing customer experience and improving the bottom line |
131 | |||
| 24 |
Enovityenovity.com
A firm of engineers optimizing facilities to maximize performance, energy efficiency, and sustainability, creating healthier environments for productivity and prosperity |
128 | |||
| 25 |
Kennedy Wilson Property Serviceskennedywilsonservices.com
Providing commercial real estate solutions including property management, brokerage, facility management, accounting, construction management, and distressed asset services nationwide |
57 | |||
| 26 |
Professional Maintenance Systemspmsjanitorial.com
A professional cleaning company with over 40 million SF of facilities in California & Washington, certified in safety, sustainability, and diversity |
56 | |||
| 27 |
Patriot Logisticspatriotadvantage.com
A logistics and facilities solutions partner serving major retailers in the Western United States, offering maintenance, redeployment, asset tracking, warehousing, transportation, and value-added services |
45 | |||
| 28 |
USC Facilities Management Servicesfpm.usc.edu
A facilities management company supporting USC's research, academic, and patient care programs, maintaining physical assets with quality service and sustainability |
30 | |||
| 29 |
Intrinzecintrinzec.com
The company specializes in providing comprehensive energy solutions through engineering, design, project management, and system integration for efficient and synchronized building systems |
1 | |||
Turn this list into pipeline
Tamtam finds the decision-makers at every company on a list like this one, with verified emails, phone numbers and the buying signals that tell you when to reach out.
How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Nov 11, 2026.
More company lists in California
- The largest companies in California 15,265
- Multinational companies in California 2,592
- SaaS companies in California 1,855
- Software Development companies in California 1,650
- AI companies in California 1,297
- Companies with in-house R&D in California 1,276
- Manufacturers in California 1,066
- Hardware manufacturers in California 985
- IT Services and IT Consulting companies in California 968
- Education providers in California 950
- Subscription businesses in California 940
- Venture capital and private equity firms in California 917
- Professional services firms in California 880
- Companies with a mobile app in California 827
- Retail chains in California 803
- IT services companies in California 796
- Venture Capital and Private Equity Principals companies in California 731
- Financial services firms in California 711
- Financial Services companies in California 642
- Healthcare providers in California 569
- AI-native companies in California 561
- Hospitals and Health Care companies in California 555
- Consulting firms in California 551
- Public sector organisations in California 535