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                                TECO ENERGY, INC.


                                       and


                              THE BANK OF NEW YORK
                                   As Trustee



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



                          FOURTH SUPPLEMENTAL INDENTURE

                           dated as of April 30, 2001

                           Supplementing the Indenture

                           dated as of August 17, 1998



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



                                  $400,000,000

                              7.20% Notes Due 2011

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                                TABLE OF CONTENTS


                                                                          PAGE

ARTICLE ONE         DEFINITIONS AND OTHER PROVISIONS OF GENERAL
                    APPLICATION............................................2

     Section 101.   Definitions............................................2

     Section 102.   Section References.....................................2

ARTICLE TWO         DESIGNATION AND TERMS OF THE NOTES.....................2

     Section 201.   Establishment of Series................................2

     Section 202.   Variations in Terms of Notes...........................3

     Section 203.   Amount and Denominations; the Depositary...............3

     Section 204.   Interest Rates and Interest Payment Dates..............3

     Section 205.   Form and Other Terms of the Notes......................3

     Section 206.   Authentication and Delivery............................4

     Section 207.   Redemption, No Sinking Fund............................4

ARTICLE THREE       APPROVAL OF AMENDMENT TO SECTION 801 OF
                    ORIGINAL INDENTURE.....................................6

ARTICLE FOUR        MISCELLANEOUS..........................................6

     Section 401.   Effect On Original Indenture...........................6

     Section 402.   Counterparts...........................................6

     Section 403.   Recitals...............................................6

     Section 404.   Governing Law..........................................6



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     This Fourth Supplemental Indenture, dated as of April 30, 2001 between TECO
Energy, Inc., a corporation duly organized and existing under the laws of the
State of Florida (hereinafter called the "COMPANY") and having its principal
office at TECO Plaza, 702 North Franklin Street, Tampa, Florida 33602, and The
Bank of New York, as trustee (hereinafter called the "TRUSTEE") and having its
principal corporate trust office at 101 Barclay Street, 21st Floor West, New
York, New York, 10286.

                                   WITNESSETH:

     WHEREAS, the Company and the Trustee entered into an Indenture, dated as of
August 17, 1998 (the "ORIGINAL INDENTURE"), pursuant to which one or more series
of debt of the Company (the "SECURITIES") may be issued from time to time; and

     WHEREAS, Section 201 of the Original Indenture permits the terms of any
series of Securities to be established in an indenture supplemental to the
Original Indenture; and

     WHEREAS, Section 901(7) of the Original Indenture provides that a
supplemental indenture may be entered into by the Company and the Trustee
without the consent of any Holders of the Securities to establish the form and
terms of the Securities of any series; and

     WHEREAS, the Company and the Trustee have entered into supplemental
indentures, including a Third Supplemental Indenture, dated as of December 1,
2000 (the "THIRD SUPPLEMENTAL INDENTURE"), pursuant to which the Company amended
Section 801 of the Original Indenture; and

     WHEREAS, the Company has requested the Trustee to join with it in the
execution and delivery of this Fourth Supplemental Indenture in order to
supplement and amend the Original Indenture by, among other things, establishing
the form and terms of one series of Securities to be known as the Company's
"7.20% Notes Due 2011" (the "NOTES") and amending and adding certain provisions
thereof for the benefit of the Holders of the Notes; and

     WHEREAS, the Company and the Trustee desire to enter into this Fourth
Supplemental Indenture for the purposes set forth in Sections 201 and 901 of the
Original Indenture as referred to above; and

     WHEREAS, the Company has furnished the Trustee with a Board Resolution
authorizing the execution of this Fourth Supplemental Indenture; and

     WHEREAS, all things necessary to make this Fourth Supplemental Indenture a
valid agreement of the Company and the Trustee and a valid supplement to the
Original Indenture have been done,

     NOW, THEREFORE, THIS FOURTH SUPPLEMENTAL INDENTURE WITNESSETH:

     For and in consideration of the premises and the purchase of the Notes to
be issued hereunder by holders thereof, the Company and the Trustee mutually
covenant and agree, for the

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equal and proportionate benefit of the respective holders from time to time of
the Notes, as follows:

                                  ARTICLE ONE

             DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION

     SECTION 101. DEFINITIONS

     All capitalized terms that are used herein and not otherwise defined herein
shall have the meanings assigned to them in the Original Indenture. The Original
Indenture together with this Fourth Supplemental Indenture are hereinafter
sometimes collectively referred to as the "INDENTURE."

     "BUSINESS DAY" shall mean any day other than a Saturday or Sunday that is
neither a legal holiday nor a day on which banking institutions are authorized
or required by law or regulations to close in the City of New York.

     "DEPOSITARY" shall have the meaning specified in Section 203 hereof.

     "INTEREST RATE" shall mean the annual rate of interest applicable to the
Notes.

     "INTEREST PAYMENT DATE" shall have the meaning set forth in Section 204(a)
hereof.

     "ORIGINAL ISSUE DATE" shall mean the date upon which the Notes are
initially issued by the Company, such date to be set forth on the face of the
Note.

     "RECORD DATE" shall mean the fifteenth calendar day (whether or not a
Business Day) immediately preceding the related Interest Payment Date.

     "STATED MATURITY DATE" shall mean May 1, 2011.

     SECTION 102. SECTION REFERENCES

     Each reference to a particular section set forth in this Fourth
Supplemental Indenture shall, unless the context otherwise requires, refer to
this Fourth Supplemental Indenture.

                                  ARTICLE TWO

                       DESIGNATION AND TERMS OF THE NOTES

     SECTION 201. ESTABLISHMENT OF SERIES

     There is hereby created a series of Securities to be known and designated
as the "7.20% Notes Due 2011" (the "NOTES"), which shall rank equally with each
other and all other unsecured and unsubordinated indebtedness of the Company.
For the purposes of the Original Indenture, the Notes shall constitute a single
series of Securities.



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     SECTION 202. VARIATIONS IN TERMS OF NOTES

     Subject to the terms and conditions set forth in the Original Indenture and
in this Fourth Supplemental Indenture, the terms of any particular Note may vary
from the terms of any other Note as contemplated by Section 301 of the Original
Indenture, and the terms for a particular Note will be set forth in such Note as
delivered to the Trustee or an Authenticating Agent for authentication pursuant
to Section 303 of the Original Indenture.

     SECTION 203. AMOUNT AND DENOMINATIONS; THE DEPOSITARY

     The aggregate principal amount of Notes that may be issued under this
Fourth Supplemental Indenture is limited to $400,000,000. The authorized
denominations of Notes shall be $1,000 or integral multiples of $1,000 in excess
thereof.

     The Notes shall be issuable only in fully registered form, without coupons,
and will initially be registered in the name of The Depository Trust Company or
its successor ("DEPOSITARY"), or its nominee who is hereby designated as "U.S.
Depositary" under the Original Indenture.

     SECTION 204. INTEREST RATES AND INTEREST PAYMENT DATES

     (a)  Interest Rate. The Notes shall bear interest at the annual rate set
forth on the face thereof (the "INTEREST RATE") from the Original Issue Date to
the Stated Maturity Date. Interest on the Notes will be payable semi-annually on
May 1 and November 1 of each year (each, an "INTEREST PAYMENT DATE"), commencing
on November 1, 2001. Such interest will be payable to the holder thereof as of
the related Record Date.

     (b)  Computation of Interest. The amount of interest payable for any period
will be computed on the basis of a year of 360 days consisting of twelve 30-day
months. Except for the effect of any adjustment in the Interest Payment Date as
provided in the following sentence, the amount of interest payable for any
period shorter than a full six-month period for which interest is computed, will
be computed on the basis of the actual number of days elapsed in such a 180-day
period. If any Interest Payment Date would otherwise be a day that is not a
Business Day, such Interest Payment Date will be postponed to the next
succeeding Business Day, and no interest will accrue on such payment for the
period from and after such Interest Payment Date to the date of such payment on
the next succeeding Business Day, except that, if such Business Day is in the
next succeeding calendar year, such payment shall be made on the immediately
preceding Business Day, in each case with the same force and effect as if made
on such date.

     SECTION 205. FORM AND OTHER TERMS OF THE NOTES

     (a)  Attached hereto as EXHIBIT A is the form of Note, which form is hereby
established as the form in which Notes may be issued.

     (b)  Subject to (a) above, any Note may be issued in such other form as may
be provided by, or not inconsistent with, the terms of the Original Indenture
and this Fourth Supplemental Indenture.


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     SECTION 206. AUTHENTICATION AND DELIVERY

     As provided in and pursuant to Section 303 of the Original Indenture, each
time that the Company delivers Notes to the Trustee or Authenticating Agent for
authentication after the initial issuance of Notes under this Indenture, the
Company shall deliver a Supplemental Company Order in the form of EXHIBIT B to
this Fourth Supplemental Indenture for the authentication and delivery of such
Notes and the Trustee or such Authenticating Agent shall authenticate and
deliver such Notes.

     SECTION 207. REDEMPTION, NO SINKING FUND

     The Notes are subject to redemption, in whole or in part, at any time, and
at the option of the Company, at a redemption price equal to the greater of:

          (i)  100% of the principal amount of Notes then outstanding to be
     redeemed, or

          (ii) the sum of the present values of the remaining scheduled payments
     of principal and interest on the Notes then outstanding to be redeemed (not
     including any portion of such payments of interest accrued as of the
     redemption date) discounted to the redemption date on a semiannual basis
     (computed based on a 360-day year consisting of twelve 30-day months) at
     the Adjusted Treasury Rate, plus 25 basis points (0.25%), as calculated by
     an Independent Investment Banker,

plus, in both of the above cases, accrued and unpaid interest thereon to the
redemption date.

     The Company will mail a notice of redemption at least 30 days but no more
than 60 days before the redemption date to each holder of Notes to be redeemed.
If the Company elects to partially redeem the Notes, the Trustee will select in
a fair and appropriate manner the Notes to be redeemed.

     Unless the Company defaults in payment of the redemption price, on and
after the redemption date, interest will cease to accrue on the Notes or
portions thereof called for redemption.

     The Notes are not entitled to the benefit of any sinking fund or analogous
provision.

     "ADJUSTED TREASURY RATE" means, with respect to any redemption date:

          (i)  the yield, under the heading which represents the average for the
     immediately preceding week, appearing in the most recently published
     statistical release designated "H.15(519)" or any successor publication
     which is published weekly by the Board of Governors of the Federal Reserve
     System and which establishes yields on actively traded United States
     Treasury securities adjusted to constant maturity under the caption
     "Treasury Constant Maturities," for the maturity corresponding to the
     Comparable Treasury Issue (if no maturity is within three months before or
     after the Remaining Life, as defined below, yields for the two published
     maturities most closely



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     corresponding to the Comparable Treasury Issue will be determined and the
     Adjusted Treasury Rate will be interpolated or extrapolated from such
     yields on a straight line basis, rounding to the nearest month); or

          (ii) if such release (or any successor release) is not published
     during the week preceding the calculation date or does not contain such
     yields, the rate per annum equal to the semi-annual equivalent yield to
     maturity of the Comparable Treasury Issue, calculated using a price for the
     Comparable Treasury Issue (expressed as a percentage of its principal
     amount) equal to the Comparable Treasury Price for such redemption date.

The Adjusted Treasury Rate will be calculated on the third Business Day
preceding the redemption date.

     "COMPARABLE TREASURY ISSUE" means the United States Treasury security
selected by an Independent Investment Banker as having a maturity comparable to
the remaining term of the Notes to be redeemed that would be used, at the time
of selection and in accordance with customary financial practice, in pricing new
issues of corporate debt securities of comparable maturity to the remaining term
of such Notes (the "REMAINING LIFE").

     "COMPARABLE TREASURY PRICE" means (1) the average of five Reference
Treasury Dealer Quotations for such redemption date, after excluding the highest
and lowest Reference Treasury Dealer Quotations, or (2) if the Independent
Investment Banker obtains fewer than five such Reference Treasury Dealer
Quotations, the average of all such quotations.

     "INDEPENDENT INVESTMENT BANKER" means Chase Securities Inc. and its
successors, or if that firm is unwilling or unable to serve as such, an
independent investment and banking institution of national standing appointed by
the Company.

     "REFERENCE TREASURY DEALER" means:

          (i)  Chase Securities Inc. and its successors; provided that, if Chase
     Securities Inc. ceases to be a primary U.S. Government securities dealer in
     New York City (a "Primary Treasury Dealer"), the Company will substitute
     another Primary Treasury Dealer; and

          (ii) up to four other Primary Treasury Dealers selected by the
     Company.

     "REFERENCE TREASURY DEALER QUOTATIONS" means, with respect to each
Reference Treasury Dealer and any redemption date, the average, as determined by
the Independent Investment Banker, of the bid and asked prices for the
Comparable Treasury Issue (expressed in each case as a percentage of its
principal amount) quoted in writing to the Independent Investment Banker at 5:00
p.m., New York City time, on the third Business Day preceding such redemption
date.


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                                 ARTICLE THREE

           APPROVAL OF AMENDMENT TO SECTION 801 OF ORIGINAL INDENTURE

     The Holders of the Notes, by their acquisition thereof, shall be deemed to
have approved the amendment of Section 801 of the Original Indenture as such
amendment is set forth in Section 701 of the Third Supplemental Indenture.

                                  ARTICLE FOUR

                                  MISCELLANEOUS

     SECTION 401. EFFECT ON ORIGINAL INDENTURE

     The Fourth Supplemental Indenture is a supplement to the Original
Indenture. As supplemented by this Fourth Supplemental Indenture, the Original
Indenture is in all respects ratified, approved and confirmed, and the Original
Indenture and this Fourth Supplemental Indenture shall together constitute one
and the same instrument.

     SECTION 402. COUNTERPARTS

     This Fourth Supplemental Indenture may be executed in any number of
counterparts, each of which so executed shall be deemed to be an original, but
all such counterparts shall together constitute by one and the same instrument.

     SECTION 403. RECITALS

     The recitals contained herein shall be taken as the statements of the
Company, and the Trustee assumes no responsibility for their correctness. The
Trustee makes no representations as to the validity or sufficiency of this
Fourth Supplemental Indenture.

     SECTION 404. GOVERNING LAW

     This Fourth Supplemental Indenture shall be governed by and construed in
accordance with the laws of the jurisdiction that govern the Original Indenture
and its construction.

              [The balance of this page intentionally left blank.]


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     IN WITNESS WHEREOF, the parties hereto have caused this Fourth Supplemental
Indenture to be duly executed as of the date and year first written above.

                                     TECO ENERGY, INC.



                                     By: /s/ Gordon L. Gillette
                                         --------------------------------------
                                         Name:  Gordon L. Gillette
                                         Title: Vice President - Finance and
                                                Chief Financial Officer


                                     THE BANK OF NEW YORK, AS TRUSTEE



                                     By: /s/ James Hall
                                         --------------------------------------
                                         Name:  James Hall
                                         Title: Vice President


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Washington                    )
                              ) SS.:
District of Columbia          )

     On the 27th day of April, 2001 before me personally came Gordon Gillette,
to me known, who, being by me duly sworn, did depose and say that s/he is Senior
Vice President, Chief Financial Officer of TECO ENERGY, INC., one of the
corporations described in and which executed the foregoing instrument.


                                         /s/ Sherrita A. Barkley
                                         ------------------------------------
                                         Notary Public



State of New York              )
                               ) SS.:
County of New York             )

     On the 30th day of April, 2001 before me personally came James Hall to me
known, who, being by me duly sworn, did depose and say that he/she is Vice
President of THE BANK OF NEW YORK, one of the corporations described in and
which executed the foregoing instrument.


                                         /s/ Jean F. Newman
                                         ------------------------------------
                                         Notary Public