Professional Employer Organizations (PEOs) can voluntarily apply to become certified as a Certified Professional Employer Organization (CPEO). Becoming and remaining certified as a CPEO means that a PEO has met the background, experience, business location, financial reporting, tax compliance, and bonding requirements described in the statute and regulationsPDF of the CPEO program. Existing and potential customers of a CPEO can verify a CPEO’s certification status by reviewing the IRS published CPEO Public Listings of currently certified CPEOs and CPEOs whose certification has been suspended or revoked. Entering into an agreement with a CPEO affects the employment tax liabilities of both the CPEO and its customers. Additional details of the employment tax liability impacts for CPEOs and their customers are provided in these regulationsPDF.