EXHIBIT 21 Subsidiaries of the Corporation The following bank subsidiaries are national banks and are organized under the laws of the United States: Associated Bank, National Association Associated Bank Green Bay, National Association Associated Bank Lakeshore, National Association Associated Bank Illinois, National Association Citizens Bank, National Association Associated Card Services Bank, National Association Associated Trust Company, National Association The following bank subsidiaries are state banks and are organized under the laws of the State of Wisconsin: Associated Bank North Associated Bank Milwaukee Associated Bank South Central The following bank subsidiaries are state banks and are organized under the laws of the State of Illinois: Associated Bank Chicago The following bank subsidiaries are state banks and are organized under the laws of the State of Minnesota: Bank Windsor The following non-bank subsidiaries are organized under the laws of the State of Wisconsin: Associated Banc-Corp Services, Inc. Associated Leasing, Inc. Associated Commercial Finance, Inc. Associated Mortgage, Inc. Associated Commercial Mortgage, Inc. Appraisal Services, Inc. Associated Investment Management Group, Associated Investment Management, Inc. LLC Associated Investment Services, Inc. Wisconsin Finance Corporation Asset Management Services of Green Bay, LLC The following non-bank subsidiaries are organized under the laws of the State of Illinois: Associated Illinois Banc-Corp Associated Great Northern Mortgage Company Citizens Financial Services, Inc. FFS Funding Corp., Inc. The Mortgage Man Company The following non-bank subsidiary is organized under the laws of the State of Arizona: Banc Life Insurance Corporation The following non-bank subsidiary is organized under the laws of the State of California: Mortgage Finance Corporation The following non-bank subsidiary is organized under the laws of the State of Delaware: UFS Capital Corporation CB Investments, Inc. The following non-bank subsidiary is organized under the laws of the State of Missouri: Illini Service Corporation The following non-bank subsidiaries are organized under the laws of the State of Nevada: ASBC Investment Corp - Green Bay ASBC Investment Corp - Neenah ASBC Investment Corp - Lakeshore ASBC Investment Corp - North ASBC Investment Corp - Milwaukee ASBC Investment Corp South Central ASBC Investment Corp - Illinois