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                                                                    Exhibit 99.3


                 [LETTERHEAD OF PAUL, HASTINGS, JANOFSKY & WALKER LLP]


                                January 31, 2002

NorthWestern Corporation
125 S. Dakota Avenue, Suite 1100
Sioux Falls, SD  57104

NorthWestern Capital Financing III
c/o NorthWestern Corporation
125 S. Dakota Avenue, Suite 1100
Sioux Falls, SD 57104

       Re: NorthWestern Capital Financing III - 8.10% Trust Preferred Securities

Members of the Board of Directors:

         We are acting as special tax counsel to NorthWestern Corporation (the
"COMPANY") in connection with the issuance by NorthWestern Capital Financing III
(the "TRUST") of an aggregate of 4,000,000 of the Trust's 8.10% Trust Preferred
Securities and up to 600,000 additional Preferred Securities if the Underwriters
exercise their full overallotment option (collectively, the "PREFERRED
SECURITIES"). In that connection, reference is made to (i) the registration
statement under the Securities Act of 1933, as amended (the "ACT"), of the
Company on Form S-3 (Registration No. 333-82707) filed with the Securities and
Exchange Commission (the "COMMISSION") on July 12, 1999, and declared effective
by the Commission on July 27, 1999 (the "REGISTRATION STATEMENT"), (ii) the
prospectus dated July 27, 1999 (the "PROSPECTUS") included in the Registration
Statement, (iii) the preliminary prospectus supplement, subject to completion,
dated January 22, 2002 and (iv) the prospectus supplement dated January 24, 2002
(the "FINAL SUPPLEMENTED PROSPECTUS") relating to the Preferred Securities.
Capitalized terms not otherwise defined herein shall have the meaning specified
in the Prospectus and the Final Supplemented Prospectus.

         We have examined the Prospectus, the Final Supplemented Prospectus and
such other documents and corporate records as we have deemed necessary or
appropriate for purposes of this opinion. In addition, we have assumed that the
Preferred Securities will be issued in accordance with the operative documents
described in the Prospectus and the Final Supplemented Prospectus.

         Based on the foregoing, we are of the opinion that the statements of
law and legal conclusions contained in the Final Supplemented Prospectus set
forth under the caption "Certain United States Federal Income Tax Consequences"
are correct in all material respects.

         We hereby consent to the filing of this opinion with the Commission as
an exhibit to the Registration Statement and to the use of our name under the
headings "Certain United States Federal Income Tax Consequences" and "Legal
Matters" in the Final Supplemented Prospectus. In giving the foregoing consent,
we do not hereby admit that we come within the category of persons whose consent
is required under Section 7 of the Act or the rules and regulations of the
Commission thereunder.

                                      Very truly yours,

                                      /s/ Paul, Hastings, Janofsky & Walker LLP