PEO and ASO arrangements can combine payroll, HR, benefits administration and risk support—but they are not the same structure. OneSource helps employers nationwide compare the models and choose an approach that fits their preferred level of support and responsibility.
Two ways to outsource employer administration
The right model depends on the services needed, the employer’s internal capabilities, workforce and risk profile. Some businesses want a comprehensive relationship with a co-employment structure; others want selected administrative help while retaining the traditional employer relationship. OneSource begins with the business rather than assuming one structure is right for everyone.
PEO: coordinated co-employment support
A Professional Employer Organization can provide payroll, HR, benefits administration, workers’ compensation and related services through a co-employment arrangement. The client continues to direct daily operations and employees while responsibilities are allocated by agreement.
ASO: selected administrative support
An Administrative Services Organization provides chosen employer-administration services without the same co-employment relationship. The client remains the employer of record and can outsource selected functions according to its needs.
Services that may be coordinated
Payroll administration
Processing, payroll taxes, reporting, deductions and specialized payroll requirements.
Human resources
Policies, onboarding, employee relations, performance processes and manager guidance.
Employee benefits
Enrollment and eligibility administration, employee communication and ongoing plan coordination.
Workers’ compensation
Coverage administration, certificates, payroll coordination, claims support and audit information.
Employee benefits include
Medical, dental, vision, life insurance, COBRA administration, Aflac and 401(k).
Employer reporting
Organized information for management, accounting and administration across connected services.
How OneSource helps you choose
A useful comparison goes beyond labels and looks at responsibilities, service scope and cost visibility.
01 — Assess priorities
Identify administrative pain points, internal resources, workforce needs and the preferred level of control.
02 — Compare structures
Review how responsibilities differ, which services are included and how costs are presented.
03 — Implement the fit
Set up selected services, document roles and establish clear contacts and recurring workflows.
Understanding co-employment
In a PEO relationship, responsibilities are allocated between the client and PEO by contract. The client generally continues to manage its business, supervise employees and make operational decisions. The PEO performs specified employer-administration functions. An ASO relationship does not use that same co-employment structure.
Transparent, understandable costs
OneSource emphasizes clear presentation of employer expenses. Payroll taxes, workers’ compensation and administrative fees should be understandable rather than disappearing inside a single percentage. A meaningful comparison considers both the price and which responsibilities, services and support are included.
Frequently Asked Questions
Which is better, a PEO or an ASO?
Neither is automatically better. A PEO may suit an employer seeking coordinated co-employment support, while an ASO may suit a business that wants selected services without co-employment.
Do we still manage employees in a PEO?
Yes. The client continues to manage daily work, business operations and employee supervision. Specific responsibilities are allocated in the agreement.
Can we choose only certain services?
An ASO arrangement is often designed around selected services. Available combinations are confirmed during the assessment.
Can the structure change as we grow?
Yes. OneSource can review the service structure as the workforce, internal team or risk profile evolves.
Compare PEO and ASO options clearly
Look at responsibilities, services and costs so you can choose a structure with confidence.