Thank you for the reply! I see I wasn't super clear in my question - in reality I think it was more than a name-change for my company. I am told to treat it like two different employers under the same CPEO (ADP). I feel like ADP, as a company who does this literally as their service, should be aware of things like this and adjust accordingly. They issued an explanation stating that "as there has not been an overpayment of the Employer portion of the Social Security taxes, there is no mechanism by which ADP TotalSource could file an amendment or refund. As a result, it appears that an individual who works for multiple unrelated clients of a CPEO and is therefore subject to separate taxable wage bases should likely be treated similar to an individual working for two separate employers outside of the CPEO agreement. Under these circumstances any excess Employee Social Security taxes withheld due to the application of more than one taxable wage base to the individual during the prior calendar year would generally be claimed as a credit on the individual's annual income tax filing and refunded directly by the IRS."
