Administrative Services Organization (ASO)

Definition

An Administrative Services Organization (ASO) provides HR, payroll, benefits administration, and sometimes workers comp coordination — but does NOT enter a co-employment arrangement. The client remains the sole legal employer for all tax, benefits, and liability purposes. The ASO operates more like an outsourced HR department than a co-employer.

The practical trade-off: ASO keeps the client in control of benefits design, carrier selection, and workers comp placement, but the client does not access PEO master plan benefits pricing or master policy workers comp pool placement. ASO pricing is typically lower than PEO PEPM because the provider isn't bundling insurance components — but the client still pays for benefits and workers comp directly, so total cost of HR is often comparable.

ASO frequently makes sense for businesses outgrowing a PEO at 150–300+ employees, or for businesses that need HR administrative help but want to maintain their own benefits stack and carrier relationships.

Common questions about Administrative Services Organization (ASO)

Related terms

• Professional Employer Organization (PEO) — A company that enters into a co-employment relationship with a client business to handle payroll, benefits, workers comp, and HR compliance.
• Co-employment — A legal arrangement where a PEO and a client business share specific employer responsibilities for the same workforce.
• Human Resources Outsourcing (HRO) — An umbrella term for outsourcing some or all HR functions to a third party, ranging from payroll-only to comprehensive PEO arrangements.

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This is one entry from our PEO glossary covering payroll, benefits, workers comp, HR compliance, and PEO mechanics. Browse all terms.