EXHIBIT 22.1 SUBSIDIARIES OF INTER-TEL, INCORPORATED Listed below are all the subsidiaries of Inter-Tel, Incorporated, as well as the jurisdiction under the laws of which each was organized, and the percentage of the outstanding voting stock of each owned by Inter-Tel, Incorporated. Percentage State or of Voting Jurisdiction Name Stock Owned of Organization - - ---- ----------- --------------- Inter-Tel Integrated Systems, Inc. 100% Arizona Inter-Tel Communications, Inc. 100% Arizona Inter-Tel Leasing, Inc. 100% Arizona Inter-Tel Midwest, Inc. 100% Delaware Inter-Tel Incorporated-New Jersey 100% Delaware Inter-Tel NetSolutions, Inc. 100% Texas Inter-Tel DataCom, Inc. 100% Delaware Southwest Telephone Systems, Inc. 100% New Mexico American Telcom Corp. of Georgia, Inc. 100% Georgia Access West, Inc. 100% Delaware Inter-Tel Equipment (UK), Ltd. 100% United Kingdom Inter-Tel Japan, Inc. 100% Japan Florida Telephone Systems, Inc. 100% Florida NTL Corporation dba ComNet of Ohio 100% Ohio 51