Wintrust Financial Corporation originates from the Midwestern United States, with its deep historical roots and corporate identity firmly anchored in the metropolitan Chicago area. The organization's foundational bank, Lake Forest Bank & Trust, opened its doors in the northern suburbs of Chicago in 1991, and the parent holding company established its official headquarters nearby in Rosemont, Illinois. While its physical branches, regional operational hubs, and customer base have expanded extensively across Illinois, Wisconsin, and neighboring states over the years, its corporate headquarters and primary administrative command remain situated in the greater Chicago region, reflecting its enduring commitment to Midwestern community development.