Participants with questions should contact the Service Center at 877.644. If you already have an account with Ohio DC you will need to Login and choose Add New Account to enroll.If you have questions, contact Ohio Deferred Compensation. Forms and Help. Forms. Help. For further information, the employee should contact our Service Center at 877-644-6457 and press 3 to speak with an Account Executive. Deferred Comp Board. Department of Civil Service.