EXHIBIT 5



                               September 12, 2003



Board of Directors
First Tennessee National Corporation
165 Madison Avenue
Memphis, TN 38103

Lady and Gentlemen:

         I have acted as counsel to First Tennessee National Corporation, a
Tennessee corporation (the "Company"), in connection with the registration on
Form S-8 (the "Registration Statement") under the Securities Act of 1933, as
amended (the "Act"), of 1,750,000 additional shares of common stock, par value
$0.625 per share, of the Company ( the "Shares") and associated stock purchase
rights (the "Rights") to be issued pursuant to the Shareholder Protection Rights
Agreement dated as of October 20, 1998 (the "Rights Agreement") between the
Company and First Tennessee Bank National Association, as Rights Agent (the
"Rights Agent"). The Shares may be issued from authorized but unissued shares to
employees of the Company and its subsidiaries upon the valid exercise of stock
options that are granted to them pursuant to the terms of the First Tennessee
National Corporation 1997 Employee Stock Option Plan, as amended and restated
(the "Plan"). I have examined the originals or copies, certified or otherwise
identified to my satisfaction, of such corporate records, certificates and other
documents, and such questions of law, as I have considered necessary or
appropriate for the purposes of this opinion.

         Upon the basis of such examination and subject to the limitations
contained herein, it is my opinion that:

1.       An additional 1,750,000 Shares (or in the aggregate, with all other
         Shares previously authorized, adjusted for stock splits, 27,950,000
         Shares) have been duly authorized for issuance pursuant to the terms of
         the Plan, which Plan has been duly adopted.

2.       Shares subject to options which are granted pursuant to the terms of
         Plan will, when issued pursuant to the terms of the Plan, be validly
         issued, fully paid and non-assessable.

3.       When such Shares have been validly issued, the rights attributable to
         such Shares will be validly issued.






         In connection with my opinion set forth in paragraph 3 above, I note
that the question whether the Board of Directors of the Company might be
required to redeem the Rights at some future time will depend upon the facts and
circumstances existing at that time and, accordingly, is beyond the scope of
such opinion.

         The foregoing opinion is limited to the federal laws of the United
States and the laws of the State of Tennessee, and I am expressing no opinion as
to the effect of the laws of any other jurisdiction.

         In rendering the foregoing opinion, I have relied as to certain
matters, to the extent I deem such reliance appropriate, on statements,
representations and other information obtained from public officials, officers
of the Company and other sources believed by me to be responsible.

         I hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to me in the Registration Statement.
In giving such consent, I do not thereby admit that I am in the category of
persons whose consent is required under Section 7 of the Act.

                                Very truly yours,


                                Clyde A. Billings, Jr.
                                Senior Vice President, Assistant General Counsel
                                            and Corporate Secretary