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


                                November 1, 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 2.02  Results of Operations and Financial Condition
---------  ---------------------------------------------

The information in this Item is furnished to, but not filed with, the Securities
and Exchange Commission solely under Item 2.02 of Form 8-K, "Results of
Operations and Financial Condition."

On November 1, 2005, Nicor Inc. issued a press release announcing preliminary
financial results for the quarter ended September 30, 2005 and providing updated
2005 earnings guidance. A copy of the press release is furnished 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 furnished as an exhibit to this report.

99.1  Press release of Nicor Inc. issued November 1, 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    November 1, 2005            /s/ RICHARD L. HAWLEY
      --------------------          ----------------------------
                                    Richard L. Hawley
                                    Executive Vice President and
                                    Chief Financial Officer



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Exhibit Index
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  Exhibit
  Number                            Description of Document
 ---------     ----------------------------------------------------------------
   99.1        Press release of Nicor Inc. issued November 1, 2005.