Spending too much on recruitment, payroll or global HR?
Operating and growing your business requires a talented team in place that you can trust. However, running HR and payroll places an immense burden on your back-office operations. In these situations, many businesses turn to Professional Employer Organizations (PEOs).
A PEO essentially “hires” your employees and acts as a co-employer. Your firm is the employer for day-to-day purposes, while the PEO takes over certain HR and payroll functions. Today, an estimated 907 PEOs are operating in the U.S., with many more overseas.
Here’s everything you must know about what PEOs are and how they work.
What is a PEO?
PEOs are specialist human resources partners that enter into co-employment relationships with businesses. You retain control of employee management functions, such as directing work, setting schedules, and managing performance. Meanwhile, your PEO manages payroll, HR, and benefits administration.
PEO isn’t simply a payroll outsourcing company but an operating model all its own. In particular, small and medium-sized businesses can reduce their costs, ensure compliance with employment law, and acquire more flexibility.
The History of PEO Services
PEO began in the U.S. in the late 1960s–1970s, when small firms began “leasing” their own employees back from third-party firms to tap group benefits, workers’ comp coverage, and HR administration they couldn’t buy efficiently alone. The arrangement solved real frictions—rising healthcare costs, payroll tax complexity, and multistate compliance—by pooling risk and purchasing power. But the model also raised legal questions: Who is the employer for tax, benefits, and liability? Early case law and ERISA/Tax Code provisions (e.g., the “leased employee” concept for retirement plans) tried to map responsibilities in a system originally built for single-employer relationships.
By the late 1980s–1990s, the industry reframed “employee leasing” as PEO (Professional Employer Organization) to distance itself from the idea that workers were interchangeable temps and to emphasize co-employment: the PEO becomes the employer for payroll/withholding/benefits, while the client retains day-to-day control of work
This period brought state-level licensing and financial assurance, third-party accreditation, and clearer allocation of duties (payroll taxes, unemployment insurance, workers’ comp). The rebrand marked a conceptual shift—from supplying labor to supplying employer infrastructure—anchored in compliance, risk management, and benefit scale.
In the 2000s–2010s, PEOs professionalized further with software platforms, self-funded benefits, and data-driven risk controls, and the U.S. codified additional certainty via the Certified PEO (CPEO) program (effective 2017), clarifying federal tax treatment. Meanwhile, the model globalized and diverged into adjacent forms: domestic PEOs continued the co-employment focus; EOR (Employer of Record) emerged for cross-border hiring; and traditional temp/staffing persisted for short-term supply.
Why Employers Choose the PEO Model
The PEO structure enables employers to achieve a variety of functions. Firstly, PEOs can be used to place your teams on so-called master benefits plans. These plans pool purchasing power to allow smaller companies to provide healthcare, life insurance, and retirement options that would usually only be available to larger companies.
Employers also take advantage of centralized payroll and tax processing, which cuts out multi-state complexity with regard to issues like paid leave mandates, local tax withholding, and ACA reporting requirements.
Based on figures from the National Association of Professional Employer Organizations (NAPEO), businesses that use PEOs can enjoy:
- Higher Growth: Data shows that businesses using PEOs achieve growth rates that are twice as fast as those companies that don’t.
- Lower Turnover: PEO-affiliated companies reduce employment churn, with turnover being up to 14% lower.
- Greater Survival Rates: In volatile economic times, businesses that are concerned about keeping their heads above water can team up with a PEO and see a reduced business failure rate of 50%.
What Does a PEO Do?
PEO services vary by the provider, bundling different services to provide a more bespoke experience to companies. However, most full-service PEOs will offer similar core services, including:
- Payroll and Tax Administration: Running payroll, income tax withholding, garnishments, issuing W-2s, and completing year-end filings.
- Benefits Administration: Administering healthcare, retirement options, life insurance, disability cover, and tracking and reporting for ACA compliance purposes.
- HR Compliance: Ensuring local, state, and federal compliance, including providing employee handbooks, leave administration guidance, harassment prevention, I-9 and eVerify workflows, and audit support.
- Workers’ Compensation and Unemployment: Coordinating claims, managing unemployment claims, and coverage placement.
- HR Support: Resources and support through access to experienced HR professionals for system administration and employee management.
How Do PEOs Work?
The most straightforward way of looking at a PEO is as an HR and payroll partner. It’s a co-employment relationship, meaning your employees are technically employed by both you and your PEO partner simultaneously.
In practice, the PEO handles HR, payroll, and compliance, whereas you retain control of your workforce’s daily work, such as setting schedules, tasks, and performance management.
Since your PEO also becomes the employer of record for tax and legal purposes, the PEO assumes liability for some HR functions. Small and medium-sized businesses benefit especially from this arrangement, since they usually lack in-house legal and compliance capabilities, exposing them to future liability complications.
1. What’s the Difference Between a PEO and an EOR?
The terms PEO and EOR often lead to significant confusion, with some believing they are two names that mean the same thing. Although there is some crossover, they’re designed to serve different needs.
A PEO enters into a co-employment relationship with you, where the PEO is the legal employer on paper for benefits administration, payroll, and taxes. In contrast, an Employer of Record (EOR) is the legal employer and the business entity.
PEOs are used when you already have an entity but need HR and payroll help. EORs are designed for companies without an established presence, such as when firms jump into new markets.
Read more in our PEO vs EOR Guide.
2. What’s the Difference Between a PEO and an HCM?
Human Capital Management (HCM) platforms also provide HR support, but the type of support differs widely. HCMs are HR software solutions, giving you dedicated tools for managing payroll, onboarding, and benefits. It’s a self-service option, and there’s no form of co-employment.
PEOs are full-service HR partners. They don’t just provide a platform for you to use. They actively run your day-to-day HR functions.
Read more in our PEO vs HRIS Guide.
3. What’s the Difference Between a PEO and an ASO?
An ASO, or Administrative Services Organization, is an outsourcing firm that takes control of employee health insurance processing. This model is also known as ‘Administrative Services Only’ involves a third-party outsourcing firm taking over the administrative and procedural aspects of health insurance.
4. What’s the Difference Between PEO and Employee Leasing?
The key difference between a PEO (Professional Employer Organization) and employee leasing lies in structure and control. A PEO enters a co-employment relationship, sharing certain employer responsibilities (like payroll, benefits, and HR compliance) while the client company retains full control over day-to-day management and hiring decisions. Employee leasing, by contrast, traditionally refers to a model where workers are supplied by an external firm for a fixed period — the leasing company remains the legal employer and can reassign staff elsewhere. In modern usage, PEOs are ongoing HR partners, while employee leasing suggests temporary or outsourced labor.
What is the IRS CPEO Program?
When using a U.S. PEO, the IRS operates the Certified Professional Employer Organization (CPEO) program. The IRS CPEO scheme is a voluntary certification requiring that PEOs meet an array of standards, including:
- Bonding
- Background checks
- Tax compliance controls
- Financial audits
All CPEO-certified PEOs are listed on the IRS website, providing complete transparency. Working with a CPEO is a strong signal that you’re working with a high-quality operator. It also allows clients to receive extra clarifications and statutory protections regarding federal employment tax liability that you won’t get from an uncertified PEO.
Who Should Consider Working With a PEO?
PEOs can be used by companies of any size in any industry, but they’re especially beneficial for:
- SMBs: Companies that want big-company benefits and ironclad compliance coverage without an in-house HR team.
- Multi–State Employers: PEOs help multi-state employers manage all the different state taxes, leave entitlements, wage-hour regulations, and other state-specific rules.
- Lean Companies: Founders who want to focus less on HR processes and more on revenue, products, and customers during their early growth stages.
- Benefits–First Companies: Entrepreneurs focused on attracting and retaining the top talent early in their growth stories through pooled purchasing.
What Are the Pros of Using a PEO?
Why should your business investigate incorporating PEO solutions into your model?
| ✓ Time Savings | Outsourcing payroll, routine HR admin, and tax filings can save you hundreds of hours every year, allowing you to focus on growth-based operations. |
| ✓ Streamlined Compliance | PEOs deftly negotiate complex compliance issues across multiple jurisdictions, reducing your liability exposure and mitigating future risk. |
| ✓ Stronger Benefits | Access more attractive benefits plans for your team that you wouldn’t have otherwise been able to obtain alone. |
| ✓ HR Expertise | Gain access to HR experts for tailored support on issues like internal policy design, performance management systems, and guidance on investigations. |
| ✓ Reduced Costs | In many cases, the costs of building your own internal HR and payroll frameworks would far exceed what it costs to enter into a co-employment relationship with a PEO partner. |
What Are the Cons of Using a PEO
PEOs aren’t suitable for every business or situation. Here are some of the potential downsides of working with a PEO:
| ✗ Limited Benefits Customization | Entering into a PEO’s master benefits plan means you only have limited plan design when compared to building your own in-house benefits system. |
| ✗ Switching Costs | Entering into or moving out of a PEO relationship for an established business can increase complexity in payroll, tax, and benefits plans. |
| ✗ Unsuitable for New Market Entry | If you’re moving into a new market and don’t yet have a legal entity, PEOs are unsuitable. Instead, you should consider either setting one up or turning to EOR services. |
How Much Do PEOs Cost?
PEOs use two pricing models:
- Per-employee-per-month (PEPM)
- Gross payroll percentage
Your costs usually include all premiums paid for workplace benefits. Some one-time fees may also need to be paid when you start the relationship. Generally, the price you pay will depend on the provider and the scope of the services you need. When comparing PEOs, always ask about what the quote includes, including taxes and fees.
What are the Alternatives to Using a PEO?
PEOs are just one solution for handling compliance, payroll, and HR. Other options are available and may be more suitable for your situation. That’s why it’s vital to explore every solution on the table before committing to one option or another.
The most prominent options are:
- In-House HR Departments: Building your own department gives you maximum control, but comes with steep overheads. These are typically only suited to larger companies.
- HR/HCM Solutions: Dedicated HR/HCM solutions are software platforms that allow you to manage your back-office functions in-house using modern integrations. However, you don’t gain access to dedicated expertise, and you’re fully liable for compliance.
- Employer of Record (EOR): An EOR is the legal employer and best used in locations where you don’t have a legal entity. These usually aren’t used in your own country but for global hiring, where complex local regulations act as a barrier to entry.
- Staffing Agencies: Staffing agencies provide temporary workers to fill gaps in your team. These arrangements provide you with limited control, which is why they’re designed primarily for seasonal or other short-term projects.
In many cases, businesses may use multiple options while still working with a PEO. For example, your company may take advantage of PEO services in the U.S., while turning to EOR partners or Global Employment Organizations (GEOs) when moving into overseas jurisdictions.
Professional Employer Organization (PEO) FAQs
No, they don’t. Despite the co-employment relationship on paper, your PEO has no power over hiring, firing, scheduling, tasks, or performance management. Under your co-employment agreement, your PEO handles benefits administration, compliance, and payroll.
Generally, any changes noticed by your existing employees will be minimal. They will see a new benefits portal and your PEO’s name on certain documents, including pay stubs and W-2s. However, beyond these differences, nothing will change regarding their day-to-day work.
No, a PEO enters into a co-employment relationship with its clients. In contrast, an EOR is a legal employer. When you use an EOR, you don’t become the legal employer, even though you gain day-to-day control over your workers.
Small and medium-sized companies are best suited to working with a PEO. Multi-state employers also use PEOs to deal with differing regulations. If you don’t want to build your own in-house HR department, a PEO is ideal for you.
Your legal risk typically goes down because you’re working with an experienced HR team, especially if they’ve been CPEO certified. Teaming up with a PEO reallocates much of the administrative liability to the PEO itself.
PEOs will configure all rules relating to employee handbooks, benefits administration, and taxes wherever you’re located. This means they’ll account for both state and local rules. It’s also your PEO’s responsibility to remain current with any law changes and adjust accordingly to keep you in compliance.
Most PEOs don’t have hard limits on employee headcounts. However, there are usually soft floors in place for between five and 10 employees, depending on the provider. In many cases, larger teams may also be able to take advantage of price breaks. If you’re working with an extremely small team, such as fewer than five employees, you may be better served by turning to an HCM solution instead.
PEOs are often used for American business entities, but some countries also have their own versions of PEOs. Generally, most domestic PEOs won’t offer their services in other jurisdictions. Either seek out a local provider of PEO services or turn to EOR providers instead.
