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    AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON NOVEMBER 30, 2004
                                                   1933 ACT FILE NO. 333-______
                                                   1940 ACT FILE NO. 811 - 03763

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                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

                             -----------------------


                            REGISTRATION STATEMENT ON
                                    FORM S-6

                            ------------------------

                FOR REGISTRATION UNDER THE SECURITIES ACT OF 1933
                     OF SECURITIES OF UNIT INVESTMENT TRUSTS

                            REGISTERED ON FORM N-8B-2

A.   EXACT NAME OF TRUST: CLAYMORE SECURITIES DEFINED PORTFOLIOS, SERIES 202

B.   NAME OF DEPOSITOR: CLAYMORE SECURITIES, INC.

C.   COMPLETE ADDRESS OF DEPOSITOR'S PRINCIPAL EXECUTIVE OFFICES:

                            Claymore Securities, Inc.
                            2455 Corporate West Drive
                              Lisle, Illinois 60532

D.   NAME AND COMPLETE ADDRESS OF AGENT FOR SERVICE:

  Copies to:

      NICHOLAS DALMASO, ESQ.                   ERIC F. FESS
      Senior Managing Director and
      General Counsel
      Claymore Securities, Inc.             Chapman and Cutler LLP
      2455 Corporate West Drive             111 West Monroe Street
      Lisle, Illinois  60532                Chicago, Illinois 60603
      (630) 784-6300                        (312) 845-3000

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     It is proposed that this filing will become effective (check appropriate
     box)

/ / immediately upon filing pursuant to paragraph (b)

/ / on (date) pursuant to paragraph (b)

/ / 60 days after filing pursuant to paragraph (a)

/ / on (date) pursuant to paragraph (a) of rule 485 or 486

/ / This post-effective amendment designates a new effective date for a
    previously filed post-effective amendment.

E. TITLE OF SECURITIES BEING REGISTERED: Units of fractional undivided
beneficial interest.

F. APPROXIMATE DATE OF PROPOSED SALE TO PUBLIC: As soon as practicable after the
effective date of the Registration Statement.

/ / Check box if it is proposed that this filing will become effective on (date)
    at (time) pursuant to Rule 487.

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The registration hereby amends this Registration Statement on such date or dates
as may be necessary to delay its effective date until the registrant shall file
a further amendment which specifically states that this Registration Statement
shall thereafter become effective in accordance with Section 8(a) of the
Securities Act of 1933 or until the Registration Statement shall become
effective on such date as the Commission, acting pursuant to said Section 8(a)
may determine.

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                 PRELIMINARY PROSPECTUS DATED NOVEMBER 30, 2004

                              SUBJECT TO COMPLETION

================================================================================

[LOGO OMITTED]

Claymore Securities Defined Portfolios, Series 202

Claymore Municipal Portfolio (6-10 years), Series 2
Claymore Municipal Portfolio (10-15 years), Series 4
IQ/Claymore New York Municipal Portfolio (10-15 years), Series 3

================================================================================

         Final prospectuses for prior Series of the Claymore Securities Defined
Portfolios are hereby incorporated by reference and used as part of a
preliminary prospectus for Claymore Securities Defined Portfolios, Series 202
(the "TRUST"). The final prospectus for the Trust is expected to be
substantially similar to the previous prospectuses. However, specific
information with respect to the Trust, including pricing, the size and
composition of the Trust's portfolio, the number of units of the Trust, dates
and summary information regarding the characteristics of securities to be
deposited in the Trust is not now available and will be different from that
shown since Trust has a unique portfolio. Accordingly, the information contained
herein with regard to the previous Trust should be considered as being included
for informational purposes only.

         The Securities and Exchange Commission has not approved or disapproved
these securities or passed upon the adequacy of this Prospectus. Any
representation to the contrary is a criminal offense.

         The information in this Prospectus is not complete and may be changed.
We may not sell these securities until the registration statement filed with the
Securities and Exchange Commission is effective. This Prospectus is not an offer
to sell the securities and it is not soliciting an offer to buy these securities
in any state where the offer or sale is not permitted.

Incorporated herein by reference is the prospectus from Claymore Securities
Defined Portfolios, Series 186 (Registration No. 333-117587) dated September 23,
2004 and Claymore Securities Defined Portfolios, Series 188 (Registration No.
333-118161) dated September 27, 2004, which shall be used as a preliminary
prospectus for Claymore Securities Defined Portfolios, Series 202. The final
prospectus for Claymore Securities Defined Portfolios, Series 186, was filed
pursuant to Rule 497 under the Securities Act on September 24, 2003 and the
final prospectus for Claymore Securities Defined Portfolios, Series 188, was
filed pursuant to Rule 497 under the Securities Act on September 29, 2003.

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                       CONTENTS OF REGISTRATION STATEMENT

     A.   Bonding Arrangements of Depositor:

     The Depositor has obtained the following Securities Dealer Blanket Bond for
its officers, directors and employees:

<Table>
<Caption>

                    INSURER/POLICY NO.                       AMOUNT
                                                          

               National Union Fire Insurance
            Company of Pittsburgh, Pennsylvania
                        959-9000                           $250,000
</Table>

         This Registration Statement comprises the following papers and
documents.

               The Facing Sheet
               The Prospectus
               The Signatures
               Consents of Counsel

         The following exhibits:

1.1   Reference Trust Agreement (to be supplied by amendment).

1.1.1 Standard Terms and Conditions of Trust (Reference is made to Exhibit 1.1.1
      to Amendment No.1 to the Registration Statement on Form S-6 for Claymore
      Securities Defined Portfolios, Series 116 (File No. 333-72828 filed on
      December 18, 2001).

2.1   Code of Ethics (Reference is made to Exhibit 2.1 to the Registration
      Statement on Form S-6 for Claymore Securities Deferred Portfolios, Series
      171 (File No. 333-112575 filed on February 19, 2004).

3.1   Opinion of counsel as to legality of the securities being registered
      including a consent to the use of its name in the Registration Statement
      (to be supplied by amendment).

3.2   Opinion of counsel as to Federal Income tax status of the securities being
      registered including a consent to the use of its name in the Registration
      Statement (to be supplied by amendment).

3.3   Opinion of counsel as to New York Income tax status of the securities
      being registered including a consent to the use of its name in the
      Registration Statement (to be supplied by amendment).


3.4   Opinion of counsel as to the Trustee and the Trust (s) including a consent
      to the use of its name in the Registration Statement (to be supplied by
      amendment).

4.1   Consent of Independent Registered Public Accounting Firm (to be supplied
       by amendment).

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                                   SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, the
Registrant, Claymore Securities Defined Portfolios, Series 202 has duly caused
this Registration Statement to be signed on its behalf by the undersigned
thereunto duly authorized, in the City of Lisle, and State of Illinois, on the
30th day of November, 2004.

                                    CLAYMORE SECURITIES DEFINED PORTFOLIOS,
                                      SERIES 202, Registrant

                                     By:   CLAYMORE SECURITIES, INC., Depositor

                                           By:      /s/ NICHOLAS DALMASO
                                                   -----------------------------
                                                       Nicholas Dalmaso

         Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed below on November 30, 2004 by the
following persons, who constitute a majority of the Board of Directors of
Claymore Securities, Inc.

<Table>
<Caption>

     SIGNATURE*                           TITLE**                               DATE
                                                                      

                                                                            )           /s/ NICHOLAS DALMASO
                                                                                        --------------------
                                                                            )               Nicholas Dalmaso
                                                                            )    By:        Attorney-in-Fact*
                                                                            )
                                                                            )
                                          Chairman of the Board of          )
DAVID HOOTEN*                             Directors                         )           November 30, 2004

/s/ CHARLES MILLINGTON                    Chief Financial Officer                       November 30, 2004
- ----------------------
    CHARLES MILLINGTON

/s/ NICHOLAS DALMASO                      Senior Managing Director,
- --------------------                      General Counsel and Director                  November 30, 2004
    NICHOLAS DALMASO


</Table>

- --------
*    An executed copy of the related power of attorney was filed as Exhibit 6.0
     to Registration Statement No. 333-98345 on August 22, 2002.

**   The titles of the persons named herein represent their capacity in and
     relationship to Claymore Securities, Inc., the Depositor.


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            CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

         The consent of Grant Thornton LLP to the use of its report and to the
reference to such firm in the Prospectus included in the Registration Statement
will be filed as Exhibit 4.1 to the Registration Statement.

                        CONSENT OF CHAPMAN AND CUTLER LLP

         The consent of Chapman and Cutler LLP to the use of its name in the
Prospectus included in the Registration Statement will be contained in its
opinions to be filed as Exhibits 3.1 and 3.2 to the Registration Statement.

                      CONSENT OF EMMET, MARVIN & MARTIN LLP

         The consent of Emmet, Marvin & Martin LLP to the use of its name in the
Prospectus included in the Registration Statement will be contained in its
opinions to be filed as Exhibits 3.3 and 3.4 to the Registration Statement.


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                                   MEMORANDUM

         Re:  Claymore Securities Defined Portfolios, Series 202

         The list of securities comprising the trust of the fund, the
evaluation, record and distribution dates and other changes pertaining
specifically to the new series, such as size and number of units of the trust in
the fund and the statement of financial condition of the new fund will be filed
by amendment.

                                    1940 ACT

                              FORMS N-8A AND N-8B-2

         Form N-8A and Form N-8B-2 were filed in respect of Claymore Securities
Defined Portfolios, Series 116 (and subsequent series) (File No. 811-03763).

                                    1933 ACT

                                  THE INDENTURE

         The form of the proposed Standard Terms and Conditions of Trust is
expected to be in all respects consistent with the form of the Standard Terms
and Conditions of Trust dated December 18, 2001 relative to Claymore Securities
Defined Portfolios, Series 116.

                                           CHAPMAN AND CUTLER LLP

Chicago, Illinois
November 30, 2004