Best PEO Companies in California
Compare Professional Employer Organizations serving California businesses. Editorial ratings are independent — featured placements are paid visibility, not endorsements.
PEO Companies Serving California
Justworks
New York, NY · Est. 2012
Insperity
Kingwood, TX · Est. 1986
TriNet
Dublin, CA · Est. 1988
ADP TotalSource
IRS CPEO ✓NationwideHQ: Roseland, NJ · Est. 1996
ADP TotalSource is the Professional Employer Organization division of ADP (NASDAQ: ADP), one of the world's largest payroll and HR companies with over 75 years of history and more than 1.1 million clients across 140+ cou…
CoAdvantage
IRS CPEO ✓NationwideHQ: Tampa, FL · Est. 1996
CoAdvantage is a Bradenton, Florida-based Professional Employer Organization founded in 1997.
Infiniti HR
NationwideHQ: Rockville, MD · Est. 2008
Infiniti HR is a Burtonsville, Maryland-based IRS CPEO certified Professional Employer Organization founded in 2004.
G&A Partners
IRS CPEO ✓RegionalHQ: Houston, TX · Est. 1995
G&A Partners is a Houston, Texas-based Professional Employer Organization founded in 1995 by Antonio Grijalva and John Allen.
Questco
RegionalHQ: The Woodlands, TX · Est. 1994
A Texas-based PEO with a strong track record in the energy and professional services sectors. Questco emphasizes a relationship-driven service model with local expertise.
FrankCrum
NationwideHQ: Clearwater, FL · Est. 1981
A family-owned PEO based in Florida serving businesses nationwide with 2-500 employees. FrankCrum is one of the few PEOs with its own insurance company, enabling highly competitive workers comp rates.
Ambrose Employer Group
RegionalHQ: Los Angeles, CA · Est. 1999
A California-focused PEO with deep expertise in the state's complex employment laws. Ambrose specializes in entertainment and technology companies navigating California compliance.
PrestigePEO
IRS CPEO ✓NationwideHQ: Melville, NY · Est. 1998
PrestigePEO is a national Professional Employer Organization headquartered in Melville, New York, serving small and mid-sized businesses across all 50 states since 1998.
Optimum Employer Solutions
IRS CPEO ✓RegionalHQ: Santa Ana, CA · Est. 2012
Optimum Employer Solutions is a Southern California-based IRS CPEO certified Professional Employer Organization serving small to mid-sized businesses across the United States.
Sequoia One PEO
IRS CPEO ✓RegionalHQ: Tempe, AZ · Est. 2012
Sequoia One PEO is a Tempe, Arizona-based IRS CPEO certified and ESAC accredited Professional Employer Organization founded in 2018, operating as part of Sequoia Consulting Group.
IntelliPro
IRS CPEO ✓NationwideHQ: San Jose, CA · Est. 2009
IntelliPro is an IRS-certified PEO headquartered in San Jose, California, specializing in HR outsourcing, payroll administration, and employee benefits management for technology companies and professional services firms…
Paychex PEO
IRS CPEO ✓NationwideHQ: Rochester, NY · Est. 1971
Paychex PEO is the co-employment division of Paychex (NASDAQ: PAYX), one of the largest HR and payroll companies in the United States with over 50 years of experience serving American businesses.
BBSI
NationwideHQ: Vancouver, WA · Est. 1965
Barrett Business Services, Inc. (BBSI) is a publicly traded (NASDAQ: BBSI) Professional Employer Organization headquartered in Vancouver, Washington.
Adams Keegan
IRS CPEO ✓NationwideHQ: Memphis, TN · Est. 1987
Adams Keegan is a Memphis, Tennessee-based PEO offering both co-employment (PEO) and administrative services organization (ASO) models.
Deel PEO
NationwideHQ: San Francisco, CA · Est. 2019
Deel PEO is the domestic U.S. co-employment offering from Deel, a San Francisco-based global HR and payroll platform founded in 2019 and valued at $16.8 billion following a $450 million Series G in May 2025.
AlphaStaff
NationwideHQ: Sunrise, FL · Est. 1997
AlphaStaff is a Sunrise, Florida-based Professional Employer Organization founded in 1997 and ESAC accredited.
Vensure Employer Services
NationwideHQ: Chandler, AZ · Est. 2004
Vensure Employer Services is one of the largest privately held PEOs in the United States, headquartered in Chandler, Arizona, and founded in 2004.
America's Back Office
IRS CPEO ✓NationwideHQ: Chandler, AZ · Est. 2000
America's Back Office is an IRS CPEO certified and ESAC accredited PEO headquartered in Chandler, Arizona, providing comprehensive HR outsourcing services to small and mid-sized businesses across the United States.
Avitus Group
NationwideHQ: Billings, MT · Est. 1994
Avitus Group is a Billings, Montana-based PEO and HR outsourcing company founded in 1994, providing payroll processing, employee benefits, workers' compensation, and HR services to businesses nationwide.
Tandem HR
RegionalHQ: Burr Ridge, IL · Est. 1998
Tandem HR is a Burr Ridge, Illinois-based PEO founded in 1998, providing payroll, benefits administration, HR support, workers' compensation, and compliance services to small and mid-sized businesses.
Modern Business Associates
NationwideHQ: Tampa, FL · Est. 1990
Modern Business Associates (MBA) is a Tampa, Florida-based PEO founded in 1990, providing co-employment services including payroll processing, employee benefits, HR administration, workers' compensation, and compliance s…
Employco USA
RegionalHQ: Westmont, IL · Est. 1997
Employco USA is a Westmont, Illinois-based PEO founded in 1997, providing payroll administration, employee benefits, HR outsourcing, workers' compensation, and compliance services to small and mid-sized businesses.
Proservice National
NationwideHQ: Honolulu, HI · Est. 2010
Proservice National is the mainland U.S. PEO extension of ProService Hawaii, providing co-employment services including payroll, benefits, HR administration, and compliance support to businesses across the continental Un…
Questco
NationwideHQ: The Woodlands, TX · Est. 2002
Questco is a national PEO headquartered in The Woodlands, Texas, providing comprehensive co-employment services to businesses across the United States.
Regis HR Group
NationwideHQ: Tampa, FL · Est. 2002
Regis HR Group is a Tampa, Florida-based national PEO providing co-employment services including payroll processing, employee benefits, HR administration, workers' compensation, and compliance support to businesses acros…
Stratus HR
NationwideHQ: South Jordan, UT · Est. 2003
Stratus HR is a South Jordan, Utah-based PEO (operating as ISI HR) providing comprehensive co-employment services to small and mid-sized businesses nationwide.
Tilson HR
RegionalHQ: Portland, OR · Est. 1999
Tilson HR is a Portland, Oregon-based PEO founded in 1999, providing payroll, employee benefits, HR administration, and compliance services to growing businesses across the Pacific Northwest and Western United States.
Xenium HR
RegionalHQ: Hillsboro, OR · Est. 1996
Xenium HR is a Hillsboro, Oregon-based PEO founded in 1996, serving small and mid-sized businesses in the Pacific Northwest.
True PEO
RegionalHQ: Scottsdale, AZ · Est. 2008
True PEO is a Scottsdale, Arizona-based Professional Employer Organization providing payroll, employee benefits, HR administration, and compliance services to small and mid-sized businesses in the Southwest and Western U…
INVO PEO
NationwideHQ: Tampa, FL · Est. 2010
INVO PEO is a Tampa, Florida-based Professional Employer Organization providing co-employment services including payroll processing, employee benefits, HR administration, workers' compensation, and compliance support to…
Shift Human Capital Management
RegionalHQ: Chicago, IL · Est. 2012
Shift Human Capital Management is a Chicago, Illinois-based PEO providing payroll, employee benefits, HR outsourcing, and compliance services to growing businesses across the Midwest and nationally.
SinglePoint Outsourcing
NationwideHQ: Scottsdale, AZ · Est. 2007
SinglePoint Outsourcing is a Scottsdale, Arizona-based PEO providing national co-employment services including payroll, employee benefits, HR administration, and compliance support to small and mid-sized businesses acros…
Saltus
RegionalHQ: Las Vegas, NV · Est. 2012
Saltus is a Las Vegas, Nevada-based PEO providing co-employment services including payroll, employee benefits, HR administration, and compliance support to businesses in Nevada and surrounding Western states, with notabl…
NetPEO
NationwideHQ: Atlanta, GA · Est. 2009
NetPEO is an Atlanta, Georgia-based PEO broker and provider offering co-employment services and PEO matching to businesses nationwide.
Total HR
RegionalHQ: San Diego, CA · Est. 2006
Total HR is a San Diego, California-based PEO (operating as Strategic HR Management Services) providing comprehensive co-employment services including payroll, employee benefits, HR administration, and compliance support…
PrimePay
NationwideHQ: West Chester, PA · Est. 1986
PrimePay is a West Chester, Pennsylvania-based payroll and PEO services company founded in 1986, providing co-employment services and payroll administration to small and mid-sized businesses nationwide.
CPE HR
RegionalHQ: Burbank, CA · Est. 2003
CPE HR is a Burbank, California-based PEO providing co-employment services to businesses primarily in California and nationally.
Employco Resources
RegionalHQ: Westmont, IL · Est. 1997
Employco Resources is a Westmont, Illinois-based PEO founded in 1997, providing payroll, employee benefits, HR outsourcing, workers' compensation, and compliance services to small and mid-sized businesses with a focus on…
MidwestHR
IRS CPEO ✓RegionalHQ: Woodridge, IL · Est. 1997
MidwestHR is a Woodridge, Illinois-based IRS-certified PEO founded in 1997, serving startups and small businesses with HR outsourcing, payroll processing, employee benefits administration, and workers' compensation.
Genesis HR
IRS CPEO ✓NationwideHQ: Burlington, MA · Est. 1991
Genesis HR Solutions is a Burlington, Massachusetts-based IRS CPEO certified PEO founded in 1991, providing co-employment services to businesses across New England and nationally.
Pinnacle PEO
RegionalHQ: Scottsdale, AZ · Est. 2005
Pinnacle PEO is a Scottsdale, Arizona-based Professional Employer Organization providing co-employment services including payroll processing, employee benefits, HR administration, and compliance support to businesses acr…
Prism HR
NationwideHQ: Hopkinton, MA · Est. 1996
PrismHR is a Hopkinton, Massachusetts-based HR technology platform and PEO services provider founded in 1996.
Choosing a PEO in California
California has the most complex employer compliance environment of any state in the country. With a statewide minimum wage of $16.90 per hour as of 2026 — and an exempt employee salary minimum of $70,304 per year — California sets standards that exceed federal requirements across nearly every area of employment law. Many California cities and counties set their own minimum wages above the state rate, requiring employers to track local ordinances by location.
The California Family Rights Act (CFRA) applies to employers with 5 or more employees — far more expansive than the federal FMLA threshold of 50. California also requires employers to provide at least 5 days (40 hours) of paid sick leave annually. The state's CalWARN Act requires 60 days advance notice for mass layoffs affecting 75 or more employees, with the notice requirement applying to a broader set of circumstances than the federal WARN Act. Effective January 1, 2026, AB 692 bans most stay-or-pay provisions in employment contracts, with penalties of $5,000 per worker for violations.
California's pay transparency law requires employers with 15 or more employees to include salary ranges in all job postings — a rule that directly impacts recruiting practices and requires careful HR coordination. The state's CPRA (California Privacy Rights Act) applies to employee data, creating documentation and disclosure obligations that most small businesses are not equipped to handle without dedicated HR support. The Workplace Know Your Rights Act (SB 294) requires employers to provide annual written notices to all employees outlining their rights under state and federal law.
California is one of the strongest arguments for using an IRS CPEO-certified PEO. The complexity of California employment law — with its overlapping state, county, and city requirements — means that compliance mistakes are expensive. Civil penalties for pay stub errors alone can reach $4,000 per employee. Late final paychecks trigger waiting time penalties of up to 30 days of wages. A CPEO-certified PEO with California expertise is not just convenient — for many businesses, it is essential risk management.
Already working with a PEO and considering a switch? PEO Alternatives has independent comparisons of the top providers to help you evaluate your options.
Frequently Asked Questions
What is the minimum wage in California in 2026?
The California statewide minimum wage is $16.90 per hour as of January 1, 2026. The minimum annual salary for exempt administrative, executive, and professional employees is $70,304. Many California cities and counties set higher local minimum wages — employers must comply with whichever rate is higher in each location where they operate.
Does California require paid family leave?
Yes. California Paid Family Leave (PFL) allows employees to take up to 8 weeks of partially paid leave to bond with a new child or care for a seriously ill family member. The California Family Rights Act (CFRA) provides additional job-protected unpaid leave rights for employers with 5 or more employees — a much lower threshold than the federal FMLA's 50-employee requirement.
What is the CalWARN Act and how does it differ from the federal WARN Act?
California's WARN Act requires employers to provide 60 days advance notice before a mass layoff, relocation, or plant closure affecting 75 or more employees — compared to the federal threshold of 50. California also applies its WARN requirements to a broader set of circumstances. Effective January 2026, SB 617 expanded the information employers must include in CalWARN notices.
Why is a PEO especially valuable for California businesses?
California has the most complex employment law environment in the United States, with overlapping state, county, and city requirements that change frequently. A PEO with California expertise helps businesses manage minimum wage compliance across locations, paid leave administration, pay transparency requirements, CalWARN obligations, and the strict pay stub and final paycheck rules that carry significant per-employee penalties.