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                                                                    EXHIBIT 8.1

                                October 11, 2001



SunTrust Banks, Inc.
303 Peachtree Street, N.E.
Atlanta, Georgia  30308

Ladies and Gentlemen:

         We have acted as tax counsel to SunTrust Banks, Inc., a Georgia
corporation (the "Company"), and to SunTrust Capital IV, a Delaware statutory
business trust (the "Trust"), in connection with the proposed offering by the
Trust of its trust preferred securities (the "Preferred Securities") as
described in that certain prospectus dated February 24, 1998 as supplemented by
a preliminary prospectus supplement dated October 10, 2001 (together, the
"Prospectus Supplement") and a final prospectus supplement to be dated on or
about October 11, 2001. The Preferred Securities will represent beneficial
ownership interests in the assets of the Trust, which will consist of
subordinated deferrable interest debentures to be issued by the Company (the
"Subordinated Debt Securities"). In connection therewith, you have requested our
opinions regarding (i) the federal income tax classification of the Subordinated
Debt Securities, (ii) the federal income tax classification of the Trust, and
(iii) the accuracy of the discussion included in the Prospectus Supplement under
the heading "Certain United States Federal Income Tax Consequences."

         In rendering the opinions expressed herein, we have examined such
documents as we have deemed appropriate including, without limitation, (i) the
Registration Statement on Form S-3 (Nos. 333-46123, 46123-01 and 46123-02) filed
with the Securities Exchange Commission on February 11, 1998 (the "Registration
Statement"), (ii) the Prospectus Supplement; (iii) the Indenture dated February
11, 1998 between the Company and Bank One N.A., formerly known as The First
National Bank of Chicago, as trustee (the "Trustee"); (iv) the form of Second
Supplemental Indenture to be entered into by the Company and the Trustee and (v)
the form of Subordinated Debt Security to be issued by the Company.

         In our examination of such documents and in our reliance upon them in
rendering our opinions, we have assumed, with your consent, that all documents
submitted to us are authentic originals or, if submitted as photocopies or
telecopies, faithfully reproduce the originals thereof,


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October 11, 2001
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that such documents have been or will be duly executed and validly signed or
filed, to the extent required, in substantially the same form as they have been
provided to us; that each executed document (as applicable) will constitute the
legal, valid, binding, and enforceable agreement of the signatory parties; that
all representations and statements set forth in such documents will be true,
accurate, and complete; and that all obligations imposed on, or covenants agreed
to by, the parties pursuant to any of such documents have been or will be
performed or satisfied in accordance with their terms. We also have obtained
such additional information, upon which we also have relied in rendering our
opinions, as we have deemed relevant and necessary through consultations with
various representatives of the Company.

         Based upon and subject to the foregoing, it is our opinion that:

                  (1) The Subordinated Debt Securities will be treated as
         indebtedness of the Company for United States federal income tax
         purposes.

                  (2) The Trust will be classified as a grantor trust and will
         not be treated as an association taxable as a corporation for United
         States federal income tax purposes. As a result, each beneficial owner
         of Preferred Securities will be required to include in its gross income
         its pro rata share of the interest or original issue discount paid or
         accrued with respect to the Subordinated Debt Securities.

                  (3) The discussion contained in that portion of the Prospectus
         Supplement under the caption "Certain United States Federal Income Tax
         Consequences" constitutes, in all material respects, a fair and
         accurate summary of the principal United States federal income tax
         consequences of the purchase, ownership, and disposition of Preferred
         Securities under current law.

         The opinions expressed herein are based upon existing statutory,
regulatory, administrative, and judicial authority in effect as of the date of
this letter, any of which may be changed at any time with retroactive effect.
Further, our opinions are based solely on the documents that we have examined
and the additional information that we have obtained. Our opinions cannot be
relied upon if any of the material facts contained in such documents or any such
additional information is, or later becomes, materially inaccurate. Our opinions
represent our legal judgment, have no official status of any kind, and are not
binding upon the Internal Revenue Service or any court.

         Finally, our opinions are limited to the tax matters specifically
addressed herein. We have not been asked to address herein, nor have we
addressed herein, any other tax consequences of the offering of the Preferred
Securities, including, but not limited to, any state, local, or foreign tax
consequences.

         We have furnished this letter in our capacity as counsel to the Company
and the Trust solely in connection with the offering of the Preferred
Securities. This letter is for the benefit of


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October 11, 2001
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the Company and the Trust and may not be relied upon for any other purpose
without our express written consent. We hereby consent, however, to the filing
of this letter as an exhibit to the Registration Statement and to reference of
our name under the captions "Certain United States Federal Income Tax
Consequences" and "Legal Matters" in the Prospectus Supplement. In giving such
consent, we do not thereby admit that we are included within the category of
persons whose consent is required under Section 7 of the Securities Act of 1933
or rules and regulations promulgated thereunder.


                                                   Very truly yours,



                                                   /s/ KING & SPALDING