Exhibit 4.16
                             SUPPLEMENTAL INDENTURE


         THIS SUPPLEMENTAL INDENTURE (this "Supplemental Indenture") is made and
entered into as of the 30th day of June, 2005 between Mississippi Power Company,
a Mississippi corporation (the "Company"), and Deutsche Bank Trust Company
Americas, a New York banking corporation, in its capacity as trustee (the
"Trustee") under the Indenture (hereinafter described), evidencing the agreement
of the parties hereto.
                                   WITNESSETH:

         WHEREAS, the Company and the Trustee, through its predecessors, are
parties to that certain Indenture dated as of September 1, 1941, as supplemented
and amended (the "Indenture");

         WHEREAS, the Company plans to redeem its First Mortgage Bonds, 6?%
Series due December 1, 2025 in the aggregate principal amount of $30,000,000
(the "Bonds") on December 1, 2005 (the "Redemption");

         WHEREAS, the Company plans to deposit, on the date hereof, with the
Trustee amounts sufficient to effectuate the Redemption in order to allow for
the defeasance of the Indenture; and

         WHEREAS, pursuant to Sections 17.01(c) and 17.01(i) of the Indenture,
the Company and the Trustee desire to enter into this Supplemental Indenture to
clarify certain terms and provisions of the Indenture and to establish the terms
and conditions for a fund pursuant to Article IX and Section 13.01 of the
Indenture in order to effectuate the Redemption and the defeasance of the
Indenture.

         NOW, THEREFORE, FOR AND IN CONSIDERATION of the premises, the mutual
promises, covenants and agreements contained herein, and other good and valuable
consideration, the receipt and sufficiency of which are hereby expressly
acknowledged, the parties hereto hereby agree as follows:

ARTICLE I
                                    Agreement

1.01 Provision for Redemption of the Bonds and Clarification. Pursuant to
Sections 17.01(c) and 17.01(i) of the Indenture, the Company and the Trustee
hereby agree that, in order to effectuate the Redemption and the defeasance of
the Indenture, for purposes of Article IX and Section 13.01 of the Indenture,
"money in a sufficient amount" and "money," respectively, shall mean (i) cash in
U.S. Dollars, (ii) U.S. Government Obligations which mature at least one day
prior to the applicable payment date and have a face value as of the date of the
deposit thereof, or (iii) a combination thereof, in each case in an amount as
will be sufficient to pay and discharge the principal of and premium (if any)
and interest on the bonds due and payable on the stated maturity (or date of
redemption, if applicable); provided, however, that in the case of subsections
(ii) and (iii) above, the Trustee shall have received irrevocable instructions
from the Company to apply such money or the proceeds of such U.S. Government
Obligations to said payments with respect to the bonds; provided, further, that
U.S. Government Obligations means securities that are direct, noncallable,
nonredeemable obligations of, or noncallable, nonredeemable obligations
guaranteed by, the United States of America for the timely payment of which
obligation or guarantee the full faith and credit of the United States of
America is pledged, or funds consisting solely of such securities, including
funds managed by the Trustee.

1.02 Full Force and Effect. Except as expressly set forth herein and as
otherwise supplemented, the Indenture shall be and remain in full force and
effect as originally written, and shall constitute the legal, valid, binding and
enforceable obligations of the Trustee and the Company.

1.03 Counterparts. This Supplemental Indenture may be executed in any number of
counterparts and by different parties hereto in separate counterparts, each of
which, when so executed and delivered, shall be deemed to be an original and all
of which counterparts, taken together, shall constitute but one and the same
instrument.

1.04 Successors and Assigns. This Supplemental Indenture shall be binding upon
and inure to the benefit of the successors and permitted assigns of the parties
hereto.










         IN WITNESS WHEREOF, the parties have executed this Supplemental
Indenture as of the date first above written.

                               MISSISSIPPI POWER COMPANY

[SEAL]


                               By:
                                   ------------------------------------
                                     Frances V. Turnage
                                     Vice President, Chief Financial Officer
                                     and Treasurer



                               DEUTSCHE BANK TRUST COMPANY AMERICAS
[SEAL]


                               By:
                                   -------------------------------------------
                                        Susan Johnson
                                        Vice President