PEO vs. ASO: Which Is Right for Your Business?

Both PEOs and ASOs help businesses manage HR administration — but the underlying structure is fundamentally different, and that difference has major financial implications for small businesses.

A PEO enters a co-employment arrangement with the client. By becoming the employer of record for tax and benefits purposes, the PEO can pool thousands of employees across its entire client base. This pooling creates the purchasing power of a large corporation — enabling small businesses to access group health insurance rates, group workers' comp rates, and Fortune 500-level benefits that would otherwise be unavailable to them.

An ASO (Administrative Services Organization) provides the same HR administration services — payroll processing, compliance support, employee handbook development — but without co-employment. The client remains the sole employer. This means the client does not gain access to the ASO's group benefits or workers' comp rates. The client must maintain its own benefits plans and workers' comp policy at individual market rates.

For most small businesses with fewer than 200 employees, the co-employment model of a PEO delivers significantly more value. The savings on workers' comp premiums and benefits costs typically more than offset the PEO fee. For larger businesses that already have competitive benefits and workers' comp rates through their own scale, an ASO may be a more cost-effective option for outsourcing HR administration.