EXHIBIT NO. 21B LIST OF SUBSIDIARIES OF THE UNITED ILLUMINATING COMPANY ------------------------------- STATE OR JURISDICTION OF INCORPORATION OR NAME UNDER WHICH NAME OF SUBSIDIARY ORGANIZATION SUBSIDIARY DOES BUSINESS ------------------ --------------------- ------------------------ United Resources, Inc. Connecticut United Resources, Inc. Xcelecom, Inc.* Connecticut Xcelecom, Inc. American Payment Systems, Inc.* Connecticut American Payment Systems, Inc. United Bridgeport Energy, Inc.* Connecticut United Bridgeport Energy, Inc. United Capital Investments, Inc.* Connecticut United Capital Investments, Inc. Precision Power, Inc.** Connecticut Precision Power, Inc. McPhee Electric Ltd., LLC** Connecticut McPhee Electric Ltd., LLC McPhee Utility Power and Signal, Ltd.** Connecticut McPhee Utility Power and Signal, Ltd. Thermal Energies, Inc.** Connecticut Thermal Energies, Inc. Precision Constructors, Inc.** Connecticut Precision Constructors, Inc. Allan Electric Co., Inc.** New Jersey Allan Electric Co., Inc. The DataStore, Incorporated** New Jersey The DataStore Incorporated Orlando Diefenderfer Electrical Pennsylvania Orlando Diefenderfer Electrical Contractors, Contractors, Inc.** Inc. Souwestcon Properties, Inc.*** Connecticut Souwestcon Properties, Inc. - ---------------------- * Subsidiary of United Resources, Inc. ** Subsidiary of Xcelecom, Inc. *** Subsidiary of United Capital Investments, Inc.