UNITED STATES
                      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 21, 2005
                Date of Report (Date of earliest event reported)



                                  NICOR INC.
            (Exact name of registrant as specified in its charter)


           Illinois                 1-7297               36-2855175
  (State or other jurisdiction   (Commission          (I.R.S. Employer
       of incorporation)         File Number)       Identification Number)


                                1844 Ferry Road
                        Naperville, Illinois 60563-9600
              (Address of principal executive offices) (Zip Code)

                                (630) 305-9500
              (Registrant's telephone number, including area code)


Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions (see General Instruction A.2. below):

[ ] Written communications pursuant to Rule 425 under the Securities Act
    (17 CFR 230.425)

[ ] Soliciting material pursuant to Rule 14a-12 under the Exchange Act
    (17 CFR 240.14a-12)

[ ] Pre-commencement communications pursuant to Rule 14d-2(b) under the
    Exchange Act (17 CFR 240.14d-2(b))

[ ] Pre-commencement communications pursuant to Rule 13e-4(c) under the
    Exchange Act (17 CFR 240.13e-4(c))


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Item 8.01  Other Events.
---------  -------------

On September 21, 2005, Nicor Inc. issued a press release announcing that the
Illinois Commerce Commission (ICC) approved a base rate increase for its natural
gas distribution company, Nicor Gas.

A copy of the press release is filed as Exhibit 99.1 to this Current Report on
Form 8-K and is incorporated herein by reference.


Item 9.01  Financial Statements and Exhibits
---------  ---------------------------------

(c)   Exhibits

The following is filed as an exhibit to this report.

99.1  Press release of Nicor Inc. issued September 21, 2005.



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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.




                                    Nicor Inc.


Date    September 21, 2005          /s/ PAUL C. GRACEY, JR.
      ----------------------        -----------------------------------
                                    Paul C. Gracey, Jr.
                                    Vice President, General Counsel and
                                    Secretary




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Exhibit Index
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  Exhibit
  Number                        Description of Document
 ---------     ----------------------------------------------------------------

    99.1       Press release of Nicor Inc. issued September 21, 2005.