Form 12B25
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549

FORM 12b-25

NOTIFICATION OF LATE FILING



SEC FILE NUMBER 1-5415

CUSIP NUMBER 148411


|X|   Form 10-K   |  |   Form 20-F   |  |   Form 11-K   |  |   Form 10-Q   |  |   Form NSAR   |  |  Form N-CSR  

For the period ended: December 31, 2005

|  |   Transition Report on Form 10-K  
|  |   Transition Report on Form 20-F  
|  |   Transition Report on Form 11-K  
|  |   Transition Report on Form 10-Q  
|  |   Transition Report on Form NSAR  

For the transition period ended: 
Read attached Instruction Sheet Before Preparing Form. Please Print or Type.


Nothing in this form shall be construed to imply that the Commission has verified any information contained herein.
If the notification related to a portion of the filing checked above, identify the item(s) to which notification relates:

     


Part I-Registrant Information
  Full name of Registrant:
Former name if Applicable:
Address of Principal Executive Office (Street and Number):
City, State and Zip Code:
A. M. Castle & Co.

3400 N. Wolf Road
Franklin Park, IL 60131


Part II-Rule 12b-25(b) and (c)
If the subject report could not be filed without unreasonable effort or expense and the registrant seeks relief pursuant to Rule 12b-25(b), the following should be completed.(Check box if appropriate.)




|X|
   

(a)    The reasons described in detail in Part III of this form could not be eliminated without unreasonable effort or expense;

(b)    The subject annual report, semi-annual report, transition report of Forms 10-K, 10-KSB, 20-F, 11-K, Form N-SAR or Form N-CSR, or portion thereof will be filed on or before the 15th calendar day following the prescribed due date; or the subject quarterly report or transition report on Form 10-Q, 10-QSB, or portion thereof will be filed on or before the fifth calendar day following the prescribed due date; and

(c)    The accountant's statement or other exhibit required by Rule 12b-25(c) has been attached if applicable.



Part III-Narrative
State below in reasonable detail the reasons why Forms 10-K, 20-F, 11-K, 10-Q, 10-QSB, N-SAR, N-CSR or the transition report portion thereof could not be filed within the prescribed time period.

     In the 4th quarter 2005 the Company decided to early adopt Statement of Financial Accounting Standard No. 123(R), "Share-Based Payment (Revised)" on a modifided retrospective basis.
      
      This early adoption developed into a more cumbersome task than anticipated. The retrospective application required the Company to reflect stock option exercising in all of the Company's financial statements for all prior reporting periods within the 2005 year 10K filing. This also required that related footnotes and other disclosures be updated. While the Company has been able to close its books and prepare its financial statements, the adoption of SFAS 123(R) placed a very large workload on the Company's accounting staff which led to the requirement of additional time to complete the 10K filing and for our auditors to complete their audit.
      
      The additional workload could not have been eliminated without unreasonable effort or expense by the Company.
      
      We expect that our 2005 Form 10K will be filed no later than March 31, 2006.

Part IV-Other Information
     (1)   Name and telephone number of person to contact in regard to this notification:

Jerry M. Aufox 847 349-2516

(Name) (Area Code) (Telephone Number)


     (2)   Have all other periodic reports required under Section 13 or 15(d) of the Securities Exchange Act of 1934 or Section 30 of the Investment Company Act of 1940 during the preceding 12 months or for such shorter period that the registrant was required to file such report(s) been filed?
|X|   Yes   |  |   No  
If the answer is no, identify report(s)

     

     (3)    Is it anticipated that any significant change in results of operations from the corresponding period for the last fiscal year will be reflected by the earnings statements to be included in the subject report or portion thereof?
|X|   Yes   |  |   No  

If so: attach an explanation of the anticipated change, both narratively and quantitatively, and, if appropriate, state the reasons why a reasonable estimate of the results cannot be made.


     Net income will decrease for the year 2004 by approximately $1.5 million as a result of the early adoption of SFAS 123(R) on a modifided retrospective basis.

A. M. Castle & Co.

Name of Registrant as Specified in Charter

Has caused this notification to be signed on its behalf by the undersigned thereunto duly authorized.


Date: March  16,  2006 By:  /s/ Lawrence A. Boik
Lawrence A. Boik
Vice President - Chief Financial Officer/Treasurer


INSTRUCTION: The form may be signed by an executive officer of the registrant or by any other duly authorized representative. The name and title of the person signing the form shall be typed or printed beneath the signature. If the statement is signed on behalf of the registrant by an authorized representative (other than an executive officer), evidence of the representative's authority to sign on behalf of the registrant shall be filed with the form.
ATTENTION

Intentional misstatements or omissions of fact constitute Federal Criminal Violations (See 18 U.S.C. 1001).