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                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549


                                    FORM 8-K

                                 CURRENT REPORT

     Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

                                December 21, 2001
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                                 Date of Report

                            NORTHWESTERN CORPORATION
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             (Exact name of Registrant as specified in its charter)

                                    DELAWARE
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                 (State or other jurisdiction of incorporation)

             0-692                                     46-0172280
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     (Commission File No.)                (IRS Employer Identification Number)

                      125 South Dakota Avenue, Suite 1100
                        Sioux Falls, South Dakota  57104
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                    (Address of Principal Executive Offices)

                                  (605) 978-2908
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              (Registrant's Telephone Number, Including Area Code)

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Item 5.   OTHER EVENTS

     On December 18, 2001, NorthWestern Corporation ("NorthWestern") and
NorthWestern Capital Financing II ("Trust II"), entered into an underwriting
agreement (the "Underwriting Agreement") with Merrill Lynch, Pierce, Fenner &
Smith Incorporated, Morgan Stanley & Co. Incorporated and Salomon Smith
Barney Inc., as Representatives of the Underwriters named in the Underwriting
Agreement, for the sale of an aggregate of 4,000,000 of Trust II's 8-1/4%
Trust Preferred Securities (Liquidation Amount $25 per Trust Preferred
Security) (the "Trust Preferred Securities"), with an overallotment option of
up to an aggregate of 600,000 additional Trust Preferred Securities of Trust
II. A copy of the Underwriting Agreement is filed as Exhibit 1.1 to this Form
8-K. The Trust Preferred Securities are a portion of the $720 million of
securities that were registered by NorthWestern, Trust II and other
registrants pursuant to a registration statement on Form S-3 under Rule
429(b) under the Securities Act of 1933, as amended, which registration
statement was declared effective on July 27, 1999 (File No. 333-82707 (the
"Registration Statement")).

     In connection with the capitalization of the Trust, NorthWestern purchased
123,712 common trust securities of the Trust (the "Trust Common Securities").
The aggregate proceeds from the sale of the Trust Preferred Securities and the
Trust Common Securities were used to purchase subordinated debt securities of
NorthWestern, designated its 8-1/4% Subordinated Deferrable Interest Debentures
due December 15, 2031 (the "Debentures").

     The opinion of Richards, Layton & Finger, P.A., special Delaware counsel to
NorthWestern and Trust II, concerning certain legal matters with respect to the
validity of the Trust Preferred Securities is filed as Exhibit 99.1 hereto. Such
opinion includes the consent of Richards, Layton & Finger, P.A. to the reference
to its name under the caption "Legal Opinions" in the Prospectus dated July 29,
1999 and under the caption "Legal Matters" in the Prospectus Supplement dated
December 18, 2001, to the Prospectus dated July 29, 1999, included in the
Registration Statement.

     The opinion of Alan D. Dietrich, general counsel to NorthWestern and Trust
II, concerning certain legal matters with respect to the validity of the
Debentures and the guarantee by NorthWestern of certain obligations relating to
the Trust Preferred Securities is filed as Exhibit 99.2 hereto.

     The consent of Paul, Hastings, Janofsky & Walker LLP, special tax
counsel to NorthWestern and Trust II, to the filing of the opinion set forth
in full under the caption "Certain United States Federal Income Tax
Consequences" in the Prospectus Supplement dated December 18, 2001, to the
Prospectus dated July 29, 1999, included in the Registration Statement and
the reference to such firm in such Prospectus Supplement is filed as Exhibit
8.1 to this Form 8-K.

     Copies of the instruments defining the rights of the holders of the Trust
Preferred Securities are filed as Exhibits 4.1 through 4.8 to NorthWestern's and
Trust II's Registration Statement on Form 8-A filed with the Securities and
Exchange Commission on December 21, 2001.

     NorthWestern is filing this Current Report on Form 8-K in order to cause
the Underwriting Agreement, the consent of its independent accountants as to
certain matters and the opinions and consents of Richards, Layton & Finger,
P.A., Alan D. Dietrick and Paul, Hastings, Janofsky & Walker LLP to be
incorporated into the Registration Statement by reference. By filing this
Current Report on Form 8-K, however, NorthWestern does not believe that any of
the Underwriting Agreements, the consent of its independent accountants the
opinions and consents of Richards, Layton & Finger, P.A., Alan D. Dietrich and
Paul, Hastings, Janofsky & Walker LLP or the information set forth herein
represent, either individually or in the aggregate, a "fundamental change" (as
such term is used in Item 512(a)(1)(ii) of Regulation S-K) in the information
set forth in the Registration Statement.


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Item 7.   FINANCIAL STATEMENTS, PRO FORMA FINANCIAL STATEMENTS, AND EXHIBITS

(c)  Exhibits

Exhibit
Number                            Description
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1.1*     Underwriting Agreement dated December 18, 2001, between NorthWestern
         and Merrill Lynch, Pierce, Fenner & Smith Incorporated, Morgan Stanley
         & Co. Incorporated and Salomon Smith Barney Inc., as Representatives of
         the Underwriters named in the Underwriting Agreement.

23.1*    Consent of Arthur Andersen, LLP.

99.1*    Opinion of Richard, Layton & Finger, P.A. with respect to the Trust
         Preferred Securities

99.2*    Opinion of Alan D. Dietrich with respect to the Subordinated Deferrable
         Interest Debentures and the Preferred Securities Guarantee relating to
         the Trust Preferred Securities to be issued by NorthWestern.

99.3*    Tax Opinion of Paul, Hastings, Janofsky & Walker LLP with respect to
         the Trust Preferred Securities

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* Filed herewith.


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                                   SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

     Date:  December 21, 2001

                                       NORTHWESTERN CORPORATION


                                       By: /s/ Kipp D. Orme
                                          ------------------------------------
                                          Kipp D. Orme
                                          Vice President - Finance and Chief
                                          Financial Officer


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                                 EXHIBIT INDEX

Exhibit
Number                            Description
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1.1*     Underwriting Agreement dated December 18, 2001, between NorthWestern
         and Merrill Lynch, Pierce, Fenner & Smith Incorporated, Morgan Stanley
         & Co. Incorporated and Salomon Smith Barney Inc., as Representatives of
         the Underwriters named in the Underwriting Agreement.

23.1*    Consent of Arthur Andersen, LLP.

99.1*    Opinion of Richard, Layton & Finger, P.A. with respect to the Trust
         Preferred Securities

99.2*    Opinion of Alan D. Dietrich with respect to the Subordinated Deferrable
         Interest Debentures and the Preferred Securities Guarantee relating to
         the Trust Preferred Securities to be issued by NorthWestern.

99.3*    Tax Opinion of Paul, Hastings, Janofsky & Walker LLP with respect to
         the Trust Preferred Securities

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* Filed herewith.



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