Optum Therapists Are you looking for a Williamstown Optum Therapist? These Williamstown Therapists accept Optum insurance. They include Optum Therapists in Williamstown, Optum psychologists and Optum counseling. A Williamstown Therapist who accepts Optum, may be in network with Optum , or you can make a claim on your Optum insurance as an out of network Optum provider. OptumHealth provides health management solutions that address the physical, mental and financial needs of consumers and organizations.