<PAGE>
                       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

                               September 15, 1999
                        (Date of earliest event reported)

                                K N Energy, Inc.
             (Exact name of Registrant as specified in its charter)


   Kansas                            1-6446                      48-0290000
 (State of                     (Commission File No.)           (IRS Employer
Incorporation)                                              Identification No.)

                              370 Van Gordon Street
                                P. O. Box 281304
                          Lakewood, Colorado 80228-8304
          (Address of principal executive offices, including zip code)

                                 (303) 989-1740
              (Registrant's telephone number, including area code)
<PAGE>
Item 5.   Other Events.

          On September 15, 1999, K N Energy, Inc., a Kansas corporation (the
"Company"), and Kinder Morgan, Inc., a Delaware corporation ("Kinder Morgan"),
issued a joint press release outlining the strategies that the Company plans to
implement following the completion of the merger in which Kinder Morgan will
become a wholly-owned subsidiary of the Company. The joint press release is
attached as Exhibit 99.1 and is incorporated by reference herein.

Item 7.   Financial Statements, Pro Forma Financial Information and Exhibits.

          (c)  Exhibits.

               99.1      Joint Press Release of the Company and Kinder Morgan,
                         issued September 15, 1999.
<PAGE>
                                    SIGNATURE

          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.

                                        K N Energy, Inc.



                                        By: /s/ Stewart A. Bliss
                                            ------------------------------------
                                        Name: Stewart A. Bliss
                                        Title:  Chairman and Chief
                                                Executive Officer

Date:  September 15, 1999
<PAGE>
                                  EXHIBIT INDEX

99.1      Joint Press Release of the Company and Kinder Morgan, issued
          September 15, 1999.
[{"type": "8-K", "sequence": "1", "description": "FORM 8-K", "secsgml_size_bytes": 2694}]
{"company-data": {"conformed-name": "K N ENERGY INC", "cik": "0000054502", "assigned-sic": "4923", "irs-number": "480290000", "state-of-incorporation": "KS", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-06446", "film-number": "99712103"}, "business-address": {"street1": "370 VAN GORDON ST", "street2": "PO BOX 281304", "city": "LAKEWOOD", "state": "CO", "zip": "80228-8304", "phone": "3039891740"}, "mail-address": {"street1": "370 VAN GORDON STREET", "street2": "P O BOX 281304", "city": "LAKEWOOD", "state": "CO", "zip": "80228-8304"}, "former-company": [{"former-conformed-name": "KN ENERGY INC", "date-changed": "19920430"}, {"former-conformed-name": "KANSAS NEBRASKA NATURAL GAS CO INC", "date-changed": "19830403"}]}
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

                               September 15, 1999
                        (Date of earliest event reported)

                                K N Energy, Inc.
             (Exact name of Registrant as specified in its charter)

   Kansas                            1-6446                      48-0290000
 (State of                     (Commission File No.)           (IRS Employer
Incorporation)                                              Identification No.)

                              370 Van Gordon Street
                                P. O. Box 281304
                          Lakewood, Colorado 80228-8304
          (Address of principal executive offices, including zip code)

                                 (303) 989-1740
              (Registrant's telephone number, including area code)
Item 5.   Other Events.

          On September 15, 1999, K N Energy, Inc., a Kansas corporation (the
"Company"), and Kinder Morgan, Inc., a Delaware corporation ("Kinder Morgan"),
issued a joint press release outlining the strategies that the Company plans to
implement following the completion of the merger in which Kinder Morgan will
become a wholly-owned subsidiary of the Company. The joint press release is
attached as Exhibit 99.1 and is incorporated by reference herein.

Item 7.   Financial Statements, Pro Forma Financial Information and Exhibits.

          (c)  Exhibits.

               99.1      Joint Press Release of the Company and Kinder Morgan,
                         issued September 15, 1999.
SIGNATURE

          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.

                                        K N Energy, Inc.

                                        By: /s/ Stewart A. Bliss
                                            ------------------------------------
                                        Name: Stewart A. Bliss
                                        Title:  Chairman and Chief
                                                Executive Officer

Date:  September 15, 1999
EXHIBIT INDEX

99.1      Joint Press Release of the Company and Kinder Morgan, issued
          September 15, 1999.