Exhibit 21-A OTTER TAIL POWER COMPANY Subsidiaries of the Registrant March 1, 1995 Company State of Incorporation Minnesota Dakota Generating Company Minnesota Otter Tail Realty Company Minnesota Otter Tail Management Corporation* Minnesota ORD Corporation* Minnesota Quadrant Co. Minnesota North Central Utilities, Inc. Minnesota Midwest Information Systems, Inc. Minnesota Midwest Telephone Co. Minnesota Osakis Telephone Company Minnesota Data Video Systems, Inc. Minnesota MIS Investments, Inc. Minnesota Mid-States Development, Inc. Minnesota Glendale Machining, Inc. Minnesota Precision Machine of North Dakota, Inc. North Dakota Dakota Machine Tool, Inc. North Dakota Aerial Contractors, Inc. North Dakota Moorhead Electric, Inc. Minnesota KFGO, Inc. North Dakota Western Minnesota Broadcasting Company Minnesota Imaging Plus, Inc. North Dakota Mobile Imaging, Inc. North Dakota Diagnostic Medical Systems, Inc. North Dakota DMS Leasing Corporation North Dakota Medical Operators and Management Corp. North Dakota BTD Manufacturing, Inc. Minnesota *Inactive