How do i contact first bank customer service? Email Do not include any personal or account information in your email. For personal account assistance contact us directly at 800-760-2265. Contact First Bank: Mailing Address First Bank Service Center 600 James S. McDonnell Blvd St. Louis, MO 63042 How do i find my routing number for firstbank? Log in to Online Banking and then select Card Management from the navigation menu under Accounts. You can also call us at 1-800-964-3444 or visit your local FirstBank branch. What is my routing number? Your routing number is 107005047.What are firstbanks hours of operation? You can also call us or visit your local FirstBank branch. What are FirstBank's hours? Our lobby hours are typically 9:00 am - 5:00 pm, Monday to Friday, and 9:00 am - 12:00 pm on Saturday. However, these hours can vary slightly by location.How do i request a callback from a firstbank representative? Request a callback from a FirstBank representative. We will call you at your convenience. Deposit checks with your phone. How do I report that my card has been lost or stolen? Log in to Online Banking and then select Card Management from the navigation menu under Accounts. You can also call us at 1-800-964-3444 or visit your local FirstBank branch.