HR Outsourcing for Mid-Size Companies: What Works, What Doesn’t, and How to Get It Right
TLDR: HR outsourcing works differently for mid-size companies (50–200 employees) than it does for small businesses or enterprises. At this size, you likely have some internal HR capacity but not enough for everything — payroll, benefits administration, compliance, recruitment, and strategic advisory all compete for the same limited headcount. The right outsourcing model fills specific gaps without duplicating what you already do well. This guide covers which functions to outsource, which models fit the 50–200 employee range, and what to watch out for as you evaluate providers.
The 50–200 employee range is where HR gets genuinely complicated. You’re too big to wing it informally — a workforce this size has enough complexity in payroll, benefits, compliance, and employee relations that gaps become expensive. But you’re often not big enough to justify a full HR department with dedicated specialists for each function.
Most companies at this stage end up with a hybrid: one or two generalist HR people trying to cover everything, stretched thin, and inevitably letting some things slip. Outsourcing specific HR functions — strategically, not wholesale — is how high-performing mid-size companies bridge that gap.
The challenge is knowing which functions to keep, which to outsource, and which model to use. This guide works through that decision practically.
What’s Different About HR at 50–200 Employees
HR outsourcing conversations often focus on small businesses — the sub-25-employee company with no HR at all — or enterprises with the budget for sophisticated HRIS platforms and dedicated vendor management teams. Mid-size companies sit in an awkward middle.
At this scale, several things are true simultaneously:
- You have real HR infrastructure. There’s probably an HRIS, a payroll system, some version of an employee handbook, and someone accountable for HR — even if that person is also doing five other things.
- Your HR needs are diversifying. As headcount grows, you’re dealing with things you didn’t at 20 people: accommodation requests, performance improvement plans, compensation benchmarking, benefits renewal complexity, and employment law compliance that gets more complicated as your workforce gets more varied.
- Your internal HR team is often under-resourced for what’s being asked of it. One generalist handling 80 employees while managing payroll, benefits, recruiting, and employee relations is not an unusual situation. It’s a recipe for burnout and compliance gaps.
- You’re still cost-sensitive. Mid-size businesses rarely have the margin to throw money at every HR problem. Outsourcing decisions need to make financial sense, not just operational sense.
Which HR Functions Make the Most Sense to Outsource at This Scale?
Not every HR function is equally suited to outsourcing at 50–200 employees. Here’s a practical breakdown:
High Value to Outsource
Payroll. Payroll processing is the most commonly outsourced HR function across all business sizes — and for good reason. It’s rule-governed, high-risk if done wrong (CRA penalties, ESA violations, employee trust issues), and labour-intensive in ways that don’t scale linearly with headcount. At 80 employees, payroll still takes almost as long as at 200 if it’s being done manually or in a low-automation system. Outsourcing payroll to a dedicated provider brings accuracy, compliance, and time savings that almost always justify the cost. Learn more in our payroll outsourcing guide.
Benefits administration. Benefits renewals, employee enrollment, plan changes, and carrier management are time-consuming and specialized. At 50–200 employees, you may have enough headcount to access better group rates, but managing the administration effectively requires benefits expertise that most HR generalists don’t have at a deep level. Outsourcing benefits administration — or working with a benefits broker who provides administrative support — frees up significant internal time while improving the employee experience around benefits.
Recruitment (for high-volume or specialized roles). If your hiring is ongoing — say, 15+ positions a year — the capacity burden on internal HR is significant. An RPO partner or recruitment outsourcing arrangement can take ownership of sourcing, screening, and coordination while keeping your employer brand front and center. For one-off niche hires, a staffing agency is typically faster and more practical.
HR compliance and policy. Employment law changes. Minimum wages, leave entitlements, accommodation obligations, pay transparency requirements — the Ontario regulatory environment has shifted considerably over the past five years. Most HR generalists stay reasonably current, but deep compliance expertise (especially for anything involving human rights complaints, termination risk, or OHSA obligations) benefits from specialist support.
Better Kept Internal
Culture and employee relations. The relationship between employees and their employer is inherently personal. Performance conversations, team conflict, manager coaching — these require knowledge of your specific people, history, and values. Outsourcing these functions wholesale typically leads to outcomes that feel impersonal and transactional.
Strategic workforce planning. Decisions about org structure, how teams are built, what roles you need in 18 months — these require deep context about your business strategy that an external provider rarely has. Internal HR, supported by a fractional CHRO or strategic consultant for specific projects, typically handles this better.
Leadership and manager development. The same principle applies. External providers can support, but this function needs internal ownership.
HR Outsourcing Models for 50–200 Employees
There are four main structures worth understanding at this company size:
Full-Service HRO (HR Outsourcing Provider)
A comprehensive HR outsourcing arrangement where a single provider handles multiple HR functions — often payroll, benefits administration, compliance, and HR administration — for a per-employee-per-month fee. This is the most complete form of outsourcing and makes sense when you want to consolidate multiple functions under one vendor relationship. Pricing typically runs $80–$200 PEPM for a full-service package at this scale.
PEO (Professional Employer Organization)
A PEO enters a co-employment relationship with your business — they become the employer of record for HR purposes, which gives employees access to PEO-negotiated benefits (often better than what a 100-person company could buy independently). PEOs work well in the US but are less common in Canada, where the co-employment model has fewer regulatory advantages. Ontario businesses evaluating PEO arrangements should understand the distinctions carefully. See our HR outsourcing vs. PEO comparison for a full breakdown.
ASO (Administrative Services Organization)
An ASO provides HR administrative support without co-employment. You remain the sole employer; the ASO handles administration, compliance support, and HR technology on your behalf. ASOs are often a better fit for Canadian mid-size companies than PEOs for this reason. The pricing tends to be lower than full-service HRO, and the scope is more modular — you can typically select which functions to include.
Fractional HR
Rather than outsourcing administrative functions, fractional HR brings in a senior HR practitioner on a part-time or retainer basis to provide strategic and generalist support. This works especially well for companies that have the operational pieces covered (payroll is running, benefits are managed) but need higher-level HR judgment: performance management, termination risk assessment, compensation structure, or organizational design. Fractional HR at 50–200 employees typically costs $2,000–$6,000/month on retainer versus $120,000–$180,000+ for a full-time HR director. Read more about the fractional HR model and how it compares to other options.
What Full-Service Outsourcing Costs at This Scale
For context on what you might pay for different outsourcing arrangements at 50–200 employees:
| Function | Typical Cost Range |
|---|---|
| Payroll outsourcing | $20–$50 PEPM, or 1–3% of payroll |
| Benefits administration | $15–$40 PEPM |
| HR administration / helpdesk | $25–$75 PEPM |
| Full-service HRO (all-in) | $80–$200 PEPM |
| Fractional HR (senior generalist) | $2,000–$6,000/month retainer |
| Recruitment (RPO, per-hire model) | 4–8% of annual salary per hire |
At 100 employees, a full-service HRO arrangement in the $100 PEPM range costs $10,000/month — roughly the equivalent of one mid-level HR specialist’s fully loaded compensation. Whether that’s a good trade depends on what you need: if you’re primarily outsourcing transactional functions, it often is. If you also need strategic HR leadership, you’ll likely need a fractional HR component as well.
Implementation: What to Expect
Transitioning HR functions to an outsourced provider at this scale takes time. Budget 60–90 days for a proper implementation. The critical path typically includes:
- Migrating payroll history and employee data to the new system
- Re-enrolling employees in benefits (ideally timed to your plan renewal)
- Transferring compliance documentation and policy acknowledgments
- Running parallel payroll for at least one cycle before cutting over
- Training managers on any new tools or processes
The transition is often where outsourcing relationships run into trouble. Providers who promise a two-week setup for a 100-person company are usually either oversimplifying or planning to cut corners. A more honest timeline is 8–12 weeks for a thorough migration.
For a full view of how to evaluate and select an HR outsourcing vendor, see our guide on HR vendor selection.
How to Decide What to Outsource
A practical approach for mid-size companies is to map your current HR functions across two dimensions: how much internal time they consume, and how specialized the expertise required is. Functions that are time-intensive and require specialized expertise you don’t have in-house are the strongest candidates for outsourcing.
Ask these questions for each HR function:
- How many internal hours per week does this take?
- What’s the compliance risk if this is done wrong?
- Do we have the expertise internally to do this well?
- Is this function a source of competitive differentiation for us, or is it commodity work?
Payroll processing, benefits administration, and standard HR compliance almost always score high on “time-consuming, compliance-critical, and not a differentiator.” Culture, leadership development, and strategic workforce planning almost always score high on “requires internal ownership.”
A Note on Ontario Compliance
For Ontario-based businesses, the regulatory environment makes careful vendor selection especially important. Your HR outsourcing provider needs to understand Ontario’s Employment Standards Act, WSIB obligations, EHT (Employer Health Tax) thresholds, OHSA requirements, and the Pay Equity Act. Not all national or US-based providers have the depth of knowledge here that the Ontario regulatory environment requires.
When evaluating vendors, ask specifically how they handle Ontario ESA compliance, how they stay current with regulatory changes, and whether their standard service includes compliance updates or bills that separately. For a broader view of the outsourcing landscape for Ontario businesses, see the HR outsourcing services overview.
When to Revisit the Model
HR outsourcing decisions aren’t permanent. At 50 employees, a comprehensive outsourcing arrangement might be the right call. At 200 employees, you may have enough volume and complexity to justify bringing some functions back in-house or hiring dedicated specialists. The 200-employee mark is roughly where many businesses find that a full internal HR team — payroll specialist, benefits coordinator, HR generalist or manager, and perhaps a recruiting lead — starts to make more economic sense than full-service outsourcing.
That transition requires planning. The goal isn’t to outsource indefinitely — it’s to have the HR infrastructure your business needs at each stage of growth, without over-investing ahead of where you are or under-investing in ways that create compounding problems.
If you want to talk through what the right HR model looks like for your company’s current size and growth trajectory, reach out to our team. We work with Ontario businesses at the 50–250 employee range to design HR structures that are practical, compliant, and built to scale with the business.