Disclosure: PEO Clarify is an independent advisory. Six PEOs (ADP TotalSource, TriNet, Paychex, G&A Partners, Justworks, Rippling) pay us a broker commission when we place clients with them. This article is analysis, not a sales pitch. If hiring in-house HR is the right call for your situation, we will say so.
One of the most common questions I get from owners in the 40-to-100 employee range: "Should I hire my first HR person or sign with a PEO?"
The answer is usually PEO, but not always. The math depends on your company size, your HR complexity, and whether you need strategic HR (culture, org design, leadership development) or operational HR (payroll, benefits, compliance, handbook).
This article runs the real numbers so you can decide.
The one-sentence answer
Under 75 employees, a PEO almost always wins on total cost and capability. Between 75 and 150, a hybrid model (in-house HR lead plus PEO services) often makes the most sense. Above 150, in-house HR plus a la carte benefits and payroll services becomes economically competitive.
The true cost of hiring in-house HR
"Hiring an HR manager" sounds like a single line item. It is not.
Per Society for Human Resource Management (SHRM) benchmarking data, an experienced HR manager in a small-to-mid-size business costs:
| Base salary (HR manager, 5-10 years experience) | $85,000 to $115,000 |
| Benefits (health, dental, vision, 401(k) match) ~25% of salary | $21,000 to $29,000 |
| Payroll taxes (FICA, FUTA, SUTA) ~8% | $6,800 to $9,200 |
| HR software subscriptions (HRIS, ATS, performance) | $3,000 to $8,000/year |
| Training, certifications, SHRM membership | $1,500 to $3,000/year |
| EPLI insurance (you still need this if HR is in-house) | $3,000 to $6,000/year |
| Legal fees for employment issues (ad hoc) | $5,000 to $15,000/year |
| Workers comp on the HR role itself (low class code) | $200 to $400/year |
| Total annual cost | $125,500 to $185,600 |
That's the cost of one HR generalist. It does not include:
- Recruiting cost to find them ($15,000 to $30,000 if you use an agency, ~$5,000 if you recruit internally)
- Onboarding and ramp time (typically 3 to 6 months before they are fully productive)
- Turnover risk (median tenure for HR generalists in SMB is 2 to 3 years per SHRM data)
- The benefits they administer (you still sponsor and pay for health insurance, 401(k), workers comp, etc. as your own group)
Add benefits that you buy as a small group and the total cost of an "in-house HR with small-group benefits" model for a 50-person company runs $200,000 to $280,000 per year above and beyond employee compensation.
The PEO cost for the same company
A 50-person PEO client runs roughly:
| PEO admin fee (~$115 PEPM x 50) | $69,000/year |
| Health insurance premium (large-group rates, employer portion) | Paid separately, typically 20-35% less than small-group |
| Workers comp (under master policy) | Covered in admin fee structure |
| EPLI coverage (under master policy) | Included |
| HR business partner + compliance support | Included |
| HRIS platform | Included |
| Employment law counsel access | Included |
| Marginal cost vs running this in-house | ~$69,000 + benefits delta savings |
The benefits delta alone is usually meaningful. Per Kaiser Family Foundation data, small-group health insurance (under 100 employees) runs 15 to 30 percent higher than large-group rates for comparable plan design. For a 50-person company with a $1,100 PEPM small-group health cost, that's $165 to $330 PEPM savings through a PEO's master plan. Over 50 employees, that's $99,000 to $198,000 in annual benefits cost reduction alone.
Side-by-side for a 50-person company
| In-House HR + Small Group Benefits | PEO | |
|---|---|---|
| HR headcount cost | $150k to $185k fully loaded | $0 (PEO provides HR services) |
| Health insurance premium (annual) | ~$660k (small group rates) | ~$540k (large-group PEO pool) |
| Workers comp (annual) | ~$6k to $20k depending on industry | Covered under master policy |
| HR software and tools | $5k to $12k/year | Included |
| EPLI insurance | $3k to $6k/year | Included |
| PEO admin fee | $0 | $69k/year |
| Legal fees (employment matters) | $5k to $15k/year | Included in PEO advisory access |
| Recruiting cost (avg every 2-3 years) | $10k to $25k amortized annually | $0 |
| Estimated annual total | $840k to $923k | $615k to $645k |
Again, these are illustrative ranges. Actual numbers depend on geography, industry, and plan design. The point is the conventional wisdom that "hiring HR is cheaper than a PEO" does not hold up once you run the full cost comparison.
What the HR manager brings that a PEO does not
Honest assessment: an in-house HR person has strengths a PEO cannot match.
- Cultural and relational continuity. A PEO HR business partner serves many clients. Your in-house person knows every employee by name, knows the history, knows the unwritten rules.
- Strategic HR work. Culture building, leadership development, org design, performance management systems, succession planning. PEOs do not do this.
- Recruiting for your specific hires. PEOs do not recruit (most of them). Your in-house HR is doing the intake, the interviews, the offer negotiations.
- Custom HR programs. Unique benefits, equity plans, wellness programs specific to your company. PEOs work with standardized menus.
- Faster internal escalations. Employee walks into HR's office at 2pm with a complaint. HR addresses it by 4pm. A PEO HR business partner may be 24 to 48 hours from responding.
What a PEO brings that in-house HR does not
- Large-group benefits pricing and richness. You cannot replicate this in-house.
- Multi-state compliance depth. A single HR generalist cannot be current on 50 states' employment law.
- 24/7 platform and HRIS infrastructure. Building this in-house is expensive.
- In-house employment law counsel at no marginal cost. A solo HR manager would need to pay $500/hour for this.
- Scale economies on workers comp, EPLI, retirement plans. Small groups cannot get these.
- Continuity through turnover. Your HR manager leaves and you lose institutional knowledge overnight. A PEO's team continues seamlessly.
The decision framework by company size
Under 25 employees: PEO
No meaningful case for in-house HR. You cannot afford a full-time HR person at this scale, part-time HR does not cover compliance, and your benefits buying power is too small. The PEO is the better tool.
25 to 75 employees: PEO
Still firmly PEO territory. You might have an office manager or people operations person handling day-to-day queries, but your HR strategy, benefits, and compliance all run through the PEO.
75 to 150 employees: Hybrid usually wins
At this size, consider hiring a senior HR leader (HR Manager or Director) who handles strategy, culture, recruiting, and leadership development, while the PEO handles transactional HR, payroll, benefits, and compliance. This is the most common mid-market structure we see.
150 to 500 employees: Depends on needs
Hybrid model works well. Some companies build out full in-house HR teams and buy benefits direct through a broker plus use a standalone payroll service. The breakeven is genuine at this size.
500+ employees: In-house HR team typically
At this scale you have the buying power to negotiate direct with insurance carriers, the budget for a full HR function, and the complexity that benefits from dedicated resources. Most companies outgrow PEOs here.
The "first HR hire" moment
For businesses that have been on a PEO for a while, a common inflection point is when you decide to hire your first dedicated HR person. That does not mean ending the PEO relationship. In fact, it is often the wrong time to leave.
The pattern we see work best: hire an HR Manager or HR Director to focus on what the PEO cannot deliver (culture, recruiting, strategic initiatives), and keep the PEO handling payroll, benefits, compliance, and transactional HR. Your HR leader's job description explicitly excludes the operational work the PEO handles.
This keeps your new HR hire focused on high-leverage strategic work instead of getting swamped by payroll questions and benefit enrollment.
Common pitfalls in this decision
- "Let's hire HR and then evaluate PEOs later." You just created a 12-month compliance gap while your new hire builds infrastructure. Most businesses this size need both for at least a period.
- "We can get by with an office manager doing HR." Until you cannot. An employment issue will surface eventually and your exposure will be real.
- "HR is a cost center we want to minimize." HR is a cost center if you think of it transactionally. HR is a profit center if it prevents one wrongful termination suit, keeps one key employee from leaving, or designs a benefits program that helps you win the war for talent.
- "We want to own our benefits." Fine, but buy them through a competitive process. Most small groups overpay 15 to 30 percent on benefits vs what they could get through a PEO's pool.
Frequently Asked Questions
Should I hire an HR manager or use a PEO?
Under 75 employees, a PEO almost always wins on cost and capability. Between 75 and 150, hybrid usually makes most sense. Above 150, depends on specifics.
How much does an HR manager cost?
An experienced HR manager costs $85,000 to $115,000 base salary, or $125,000 to $185,000 fully loaded with benefits, taxes, tools, and overhead.
At what employee count should I hire a dedicated HR person?
The SHRM benchmark is one HR headcount per 100 employees. Most businesses hire their first dedicated HR role between 75 and 125 employees.
Can I have both a PEO and an in-house HR person?
Yes, and many mid-market companies do. HR director handles strategy, culture, recruiting. PEO handles payroll, benefits, compliance, transactional HR.
Does a PEO really replace an HR manager?
For companies under 75 employees, yes. The PEO's HR business partner handles what an internal HR generalist would handle. For strategic HR, you still need a person.
What are the hidden costs of hiring in-house HR?
Benefits (20-30% of salary), payroll taxes, HR software, training, workers comp, EPLI, legal fees, and recruiting/onboarding costs every 2-3 years for turnover.
How long does a typical HR manager stay in the role?
Median tenure for HR generalists in small-to-mid-size businesses is 2 to 3 years per SHRM data.
What if I can't find a good HR manager to hire?
Talent is actually the biggest hidden cost of the in-house path. Good HR generalists are in high demand. The best ones cost $130,000+ and are often poached within 18 months. A PEO gives you instant access to a team without the hiring risk.
Not sure which fits your situation?
Tell us your size, growth plans, and current HR setup. We will run the specific math for your situation and tell you honestly whether a PEO, in-house HR, or hybrid makes more sense. No sales pressure.
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