American Chartered Bank is now MB Financial MB Financial Bank N.A. is a Chicago-based commercial bank with a more than one hu ... ndred year history of building deep and lasting relationships with middle-market companies and individuals. MB Financial Bank offers a full range of powerful financial solutions and the expertise and experience of bankers who are focused on their clients’ success. MB Financial Bank is a wholly-owned subsidiary of MB Financial, Inc. (NASDAQ: MBFI). Member FDIC. Equal Housing Lender. Specialties: Commercial banking, Wealth management, Treasury management, Business banking, Credit cards, Capital Markets, Asset Based Lending, Commercial Real Estate, Retail Banking, Mortgages read more