Contact Us If you want to learn more about co-employment and if your organization is a fit for Simploy, please fill out the form below, or just give our CEO a call: Jay King at 314-375-0030. We're here to help. If you are an existing client, call us anytime. If you want to be a client, call right now! If you are one of our co-employees and have a question, please click here. Simploy, Inc. 13023 Tesson Ferry Road, Suite 105 St. Louis, MO 63128 Office: (314) 544-1700 Toll-Free: (866) 447-3476 Fax: (314) 544-1760 If you are one of our co-employees and have a question, please click here.