FIRST AMENDMENT


     THIS FIRST AMENDMENT,  dated as of March 24, 1999, to the Rights Agreement,
dated as of August  1,  1997  (the  "Rights  Agreement"),  between  New  Century
Energies,  Inc. (the  "Company")  and The Bank of New York, as Rights Agent (the
"Rights Agent").

     WHEREAS, the parties hereto are parties to the Rights Agreement.

     WHEREAS,  pursuant  to  Section 27 of the  Rights  Agreement,  the Board of
Directors  deems it necessary  and  desirable  and in the best  interests of the
Company and its  shareholders to amend the Rights  Agreement as set forth below;
and

     WHEREAS,  the  parties  hereto  desire to amend the  Rights  Agreement,  as
provided herein,

     NOW,  THEREFORE,  in  consideration of the premises and the mutual promises
set forth  herein and in the  Rights  Agreement,  the  parties  hereto  agree as
follows:

     1. The definition of "Acquiring Person" as set forth in Section 1(a) of the
Rights Agreement is hereby amended by adding the following  provision at the end
of the first sentence thereto:

     "; provided,  however, that Northern States Power Company ("NSP") shall not
     be deemed an "Acquiring Person" as a result of the execution,  delivery and
     performance  of the Agreement  and Plan of Merger (the "Merger  Agreement")
     dated as of March 24, 1999, between NSP and the Company or the consummation
     of the transactions contemplated in the Merger Agreement".

     2. Clause (a)(i) of Section 7 of the Rights  Agreement is hereby amended to
read in its entirety as follows:

     "the  earlier of the close of business  on July 31, 2007 or the  "Effective
     Time" as defined in Merger Agreement (the "Final Expiration Date")".

     3. Clause (a) of Section 13 of the Rights  Agreement  is hereby  amended by
adding the words "other than pursuant to the Merger Agreement" at the end of the
introductory  phrase "In the event that,  following the Shares Acquisition Date,
directly or indirectly," of such clause.

     4. This Amendment shall be governed by and construed in accordance with the
laws of the State of Delaware  applicable  to contracts to be made and performed
entirely  within such State,  except that the rights,  duties and obligations of
the Rights Agent under this Amendment shall be governed by the laws of the State
of New York.

     5. Except as expressly amended hereby,  the Rights Agreement shall continue
in full force and effect in accordance with the provisions thereof.

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     6. This Amendment may be executed in any number of counterparts and each of
such  counterparts  shall for all purposes be deemed to be an original,  and all
such counterparts together constitute but one and the same instrument.

     IN WITNESS  WHEREOF,  the Company and the Rights Agent have  executed  this
First Amendment as of the date first above written.

                                NEW CENTURY ENERGIES, INC.



                                By:           /s/ Bill D. Helton
                                         Name:    Bill D. Helton
                                         Title:   Chief Executive Officer
Attest:


     /s/ Cathy J. Hart
Name:    Cathy J. Hart
Title:   Secretary




                                           THE BANK OF NEW YORK



                                           By:           /s/ Kevin Brennan
                                                    Name:    Kevin Brennan
                                                    Title:   Vice President
Attest:


     /s/ Daniel Egan
Name:    Daniel Egan
Title:   Assistant Vice President

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