**Exhibit 21**

MARSHALL & ILSLEY CORPORATION 

SUBSIDIARIES 

February 28, 2006 

Subsidiaries Incorporated or Organized inWisconsin 

    Kirchman Corporation 

    M&I Bank of Mayville 

    M&I Marshall & Ilsley Bank 

    M&I Brokerage Services, Inc. 

    M&I Capital Markets II, L.L.C. 

    M&I Community Development Corporation 

    M&I Dealer Finance, Inc. 

    M&I Equipment Finance Company 

    M&I Insurance Services, Inc. 

    M&I Investment Management Corp. 

    M&I Investment Partners Management, LLC 

    M&I Investment Partners I, Limited Partnership 

    M&I Mortgage Corp. 

    M&I Realty Advisors, Inc. 

    M&I Support Services Corp. 

    Metavante Corporation 

    Metavante Operations Resources Corporation 

    Milease, LLC 

    Printing for Systems, Inc. 

    Response DataCorp. 

    Richter-Schroeder Company, Inc. 

Subsidiaries Incorporated in Arizona 

    M&I Insurance Company of Arizona, Inc. 

Subsidiaries Incorporated in California 

    Loansoft, Inc. 

Subsidiaries Incorporated or Organized in Delaware 

    AdvancedFinancial Solutions LLC 

    AdminiSource Holdings, Inc. 

    Brasfield Technology LLC 

    Kirchman Company LLC 

    M&I Capital Markets Group L.L.C. 

    M&I Capital Trust A 

    M&I Capital Trust B 

    M&I Dealer Auto Securitization, LLC 

    M&I Northwoods I LLC 

    M&I Northwoods II LLC 

    M&I Northwoods III LLC 

    M&I Ventures L.L.C. 

    Metavante Acquisition Company LLC 

    Metavante Payment Services, LLC 

    NYCE Corporation 

    Prime Associates, Inc. 

    VECTORsgi, Inc.

Subsidiaries Incorporated in Michigan 

    MBI Benefits, Inc. 

Subsidiaries Incorporated in Minnesota 

    M&I Business Credit, Inc. 

    Two Gophers, L.L.C. 

Subsidiaries Incorporated or Organized in Missouri 

    Louisville Realty Company 

    SWB Holdings, Inc. 

    SWB Holdings A 

    SWB Holdings B 

    SWB Holdings C 

    SWB Investment II Corporation 

    SouthwestBank of St. Louis 

Subsidiaries Incorporated or Organized in Nevada 

    M&I Custody of Nevada, Inc. 

    M&I Marshall & Ilsley Holdings, Inc. 

    M&I Marshall & Ilsley Holdings II, Inc. 

    M&I Marshall & Ilsley Investment Corporation 

    M&I Marshall & Ilsley Investment II Corporation 

    M&I Mortgage Pass-Through Business Trust Series, 2004-1 

    M&I Portfolio Services, Inc. 

    M&I Servicing Corp. 

    M&I Zion Holdings, Inc. 

    M&I Zion Investment Corporation 

    M&I Zion Investment II Corporation 

    SWB Investment Corporation 

    TREEV LLC 

Subsidiaries Incorporated or Organized in Oklahoma 

    AdvancedFinancial Solutions, Inc. 

    Endpoint Exchange LLC 

    Medical Banking Exchange LLC 

Subsidiaries Incorporated in Pennsylvania 

    GHR Systems, Inc. 

Subsidiaries Incorporated in Tennessee 

    Link2Gov Corp.

Subsidiaries Organized in Texas 

    AdminiSource Communications, L.P. 

    MACL,LLC 

Subsidiaries Incorporated in Vermont 

    M&I Mortgage Reinsurance Corporation 

Subsidiaries Organized Under the Laws of the United States 

    M&I Bank FSB 

    Marshall & Ilsley Trust Company National Association 

Subsidiaries Organized Under the Laws of Canada 

    Everlink Payment Services, Inc.

    Metavante Canada Corporation 

    6027580 Canada, Inc. 

    GHR Systems Canada, Inc.