<PAGE>

                                                                    EXHIBIT 4.13

                       Subordinated Step-Up Notes due 2015

No. 001                                                              $35,000,000

         CUSIP NO.       144A-90984P DC 6

                          UNITED COMMUNITY BANKS, INC.

promises to pay to CEDE & CO., or registered assigns,
the principal sum of THIRTY-FIVE MILLION
Dollars ($35,000,000) on September 30, 2015.
Interest Payment Dates:  March 31 and September 30.
Record Dates:  March 15 and September 15.

                    UNITED COMMUNITY BANKS, INC.

         (SEAL)     By:_________________________________________________________
                    Name: Rex S. Schuette
                    Title: Executive Vice-President and Chief Financial Officer

WITNESS:

By:_________________________________________
Name: Thomas C. Gilliland
Title: Secretary

This is one of the Notes referred to in the within-mentioned Indenture:

Dated:  September 24, 2002

MARSHALL & ILSLEY TRUST COMPANY N.A.,
AS TRUSTEE

By: ________________________________________
    Authorized Signatory

<PAGE>

                       SUBORDINATED STEP-UP NOTES DUE 2015

         THIS NOTE IS NOT A DEPOSIT OR AN OBLIGATION OF ANY DEPOSITORY
INSTITUTION, IS NOT INSURED OR GUARANTEED BY THE FEDERAL DEPOSIT INSURANCE
CORPORATION OR ANY GOVERNMENT AGENCY, AND IS NOT SECURED.

         UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR SECURITIES IN
DEFINITIVE FORM, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE
DEPOSITARY TO A NOMINEE OF THE DEPOSITARY, OR BY ANY SUCH NOMINEE OF THE
DEPOSITARY, OR BY THE DEPOSITARY OR NOMINEE OF A SUCCESSOR DEPOSITARY, OR ANY
NOMINEE TO A SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY.
TRANSFERS OF THIS GLOBAL NOTE SHALL BE LIMITED TO TRANSFERS IN WHOLE, BUT NOT IN
PART, TO NOMINEES OF CEDE & CO., OR TO A SUCCESSOR THEREOF OR SUCH SUCCESSOR'S
NOMINEE, AND TRANSFERS OF PORTIONS OF THIS GLOBAL NOTE SHALL BE LIMITED TO
TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN THE INDENTURE.

         UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF
THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION ("DTC"), TO THE COMPANY OR
ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE
ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS IS
REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT HEREON IS MADE
TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR
OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER
HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

         THIS NOTE (OR ITS PREDECESSOR) HAS NOT BEEN REGISTERED UNDER THE U.S.
SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), AND, ACCORDINGLY, MAY
NOT BE OFFERED, SOLD, PLEDGED OR OTHERWISE TRANSFERRED WITHIN THE UNITED STATES
OR TO, OR FOR THE ACCOUNT OR BENEFIT OF, ANY U.S. PERSONS, EXCEPT AS SET FORTH
IN THE NEXT SENTENCE. BY ITS ACQUISITION HEREOF OR OF A BENEFICIAL INTEREST
HEREIN, THE HOLDER:

                  (A)      REPRESENTS THAT (1) IT IS A "QUALIFIED INSTITUTIONAL
         BUYER" (AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT) (A "QIB"), OR
         (2) IT HAS ACQUIRED THIS NOTE IN AN OFFSHORE TRANSACTION IN COMPLIANCE
         WITH REGULATION S UNDER THE SECURITIES ACT;

                  (B)      AGREES THAT IT WILL NOT RESELL OR OTHERWISE TRANSFER
         THIS NOTE EXCEPT (1) TO THE COMPANY OR ANY OF ITS SUBSIDIARIES, (2) TO
         A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A QIB PURCHASING FOR
         ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QIB IN A TRANSACTION MEETING
         THE REQUIREMENTS OF RULE 144A, (3) IN AN OFFSHORE TRANSACTION MEETING
         THE REQUIREMENTS OF RULE 903 OR 904 OF REGULATION S OF THE SECURITIES
         ACT, (4) IN A TRANSACTION MEETING THE REQUIREMENTS OF RULE 144 UNDER
         THE SECURITIES ACT, (5) IN ACCORDANCE WITH ANOTHER EXEMPTION FROM THE
         REGISTRATION REQUIREMENTS OF THE SECURITIES ACT (AND BASED UPON AN
         OPINION OF COUNSEL ACCEPTABLE TO THE COMPANY), OR (6) PURSUANT TO AN
         EFFECTIVE REGISTRATION STATEMENT AND, IN EACH CASE, IN ACCORDANCE WITH
         THE APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES OR ANY
         OTHER APPLICABLE JURISDICTION;

                  (C)      AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM
         THIS NOTE OR AN INTEREST HEREIN IS TRANSFERRED A NOTICE SUBSTANTIALLY
         TO THE EFFECT OF THIS LEGEND; AND

                                      -2-

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                  (D)      ACKNOWLEDGES AND AGREES THAT THE COMPANY AND THE
         TRUSTEE HAVE RESERVED THE RIGHT, PRIOR TO ANY SUCH OFFER, SALE, PLEDGE
         OR OTHER TRANSFER (I) PURSUANT TO CLAUSE (B)(3) PRIOR TO THE END OF THE
         40-DAY DISTRIBUTION COMPLIANCE PERIOD WITHIN THE MEANING OF REGULATION
         S UNDER THE SECURITIES ACT, PURSUANT TO RULE 904 OF REGULATION S, OR
         (II) PURSUANT TO CLAUSE (B)(4) PRIOR TO THE RESALE RESTRICTION
         TERMINATION DATE UNDER RULE 144, TO REQUIRE THE DELIVERY OF AN OPINION
         OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH
         OF THEM, AND TO REQUIRE THAT A CERTIFICATE OF TRANSFER IN THE FORM
         APPEARING ON THIS NOTE BE COMPLETED AND DELIVERED BY THE TRANSFEROR TO
         THE TRUSTEE. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF A HOLDER
         AFTER THE RESALE RESTRICTION TERMINATION DATE.

                  AS USED HEREIN, THE TERMS "OFFSHORE TRANSACTION" AND "UNITED
         STATES" HAVE THE MEANINGS GIVEN TO THEM BY RULE 902 OF REGULATION S
         UNDER THE SECURITIES ACT. THE INDENTURE CONTAINS A PROVISION REQUIRING
         THE TRUSTEE TO REFUSE TO REGISTER ANY TRANSFER OF THIS NOTE IN
         VIOLATION OF THE FOREGOING.

         Capitalized terms used herein shall have the meanings assigned to them
in the Indenture referred to below unless otherwise indicated.

                                      -3-

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                         (REVERSE OF SUBORDINATED NOTE)

         1.       INTEREST. United Community Banks, Inc., a Georgia corporation
(the "Company"), promises to pay interest on the principal amount of this Note
at the rate of 6.25% per annum from the Issue Date until September 30, 2010, and
at the rate of 7.50% per annum thereafter until maturity or any earlier
Redemption Date. The Company will pay interest semiannually in arrears on March
31 and September 30 of each year, or if any such day is not a Business Day, on
the next succeeding Business Day (each an "Interest Payment Date"). Interest on
the Notes will accrue from the most recent date on which interest has been paid
or, if no interest has been paid, from the date of original issuance; provided,
however, that if there is no existing Default in the payment of interest, and if
this Note is authenticated between a record date referred to on the face hereof
and the next succeeding Interest Payment Date, interest shall accrue from such
next succeeding Interest Payment Date; and, provided further, that the first
Interest Payment Date shall be September 30, 2003. The Company shall pay
interest (including post-petition interest in any proceeding under any
Bankruptcy Law) on overdue principal and premium, if any, and interest on
overdue installments of interest, to the extent lawful, at a rate per annum
equal to the rate of interest applicable to the Notes. All such default interest
shall be payable on demand. Interest will be computed on the basis of a 360-day
year comprised of twelve 30-day months.

         2.       METHOD OF PAYMENT. The Company will pay interest on the Notes
(except defaulted interest) to the Persons who are registered Holders of Notes
at the close of business on March 15 or September 15 immediately preceding the
Interest Payment Date, even if such Notes are canceled after such record date
and on or before such Interest Payment Date, except as provided in Section 2.14
of the Indenture with respect to defaulted interest. The Notes will be payable
as to principal, premium, and interest, if any, at the office or agency of the
Company maintained for such purpose or, at the option of the Company, payment of
interest, if any, may be made by check mailed to the Holders at their addresses
set forth in the register of Holders; provided, however, that payment by wire
transfer of immediately available funds will be required with respect to
principal of, and premium and interest, if any, on all Global Notes and all
other Notes the Holders of which shall have provided appropriate wire transfer
instructions to the Company or the Paying Agent. Until otherwise designated by
the Company, the Company's office or agency will be the office of the Trustee
maintained for such purpose. Such payment shall be in such coin or currency of
the United States of America as at the time of payment is legal tender for
payment of public and private debts.

         3.       PAYING AGENT AND REGISTRAR. Initially, Marshall & Ilsley Trust
Company N.A., the Trustee under the Indenture, will act as Paying Agent and
Registrar. The Company may change any Paying Agent or Registrar without notice
to any Holder. The Company or any of its Subsidiaries may act in any such
capacity.

         4.       INDENTURE. The Company issued this Note under an Indenture
dated as of September 24, 2003 (as the same may be amended, modified or
supplemented from time to time, the "Indenture") by and between the Company and
the Trustee. The terms of the Notes include those stated in the Indenture and
those made a part of the Indenture by reference to the Trust Indenture Act of
1939, as amended (15 U.S. Code Sections 77aaa-77bbbb) (the "TIA"). The Notes are
subject to all such terms and Holders are referred to the Indenture and the TIA
for a statement of such terms. The Notes are subordinated unsecured obligations
of the Company. The Notes include the Original Notes issued on the Closing Date
and any Additional Notes issued thereafter, and are treated as a single class of
securities under the Indenture. This is one of the Original Notes referred to in
the Indenture. The Holders of Notes are subject to, and entitled to all of the
benefits of, the Indenture.

         5.       REDEMPTION. The Company shall have the option, but not the
obligation, to redeem the Notes then outstanding in whole but not in part at par
on September 30, 2010, and on every September 30 thereafter until September 30,
2014, as described more fully in Section 2.16 of the Indenture.

         6.       SUBORDINATION. The Notes are subordinated in right of payment,
in the manner and to the extent set forth in the Indenture, to the prior payment
in full of all Senior Debt, whether outstanding on the Closing Date or
thereafter created, incurred, assumed or guaranteed. Each Holder by its
acceptance hereof agrees to be bound by such provisions and authorizes and
expressly directs the Trustee, on its behalf, to take such action as may be
necessary or appropriate to effectuate the subordination provided for in the
Indenture and appoints the Trustee its attorney-in-fact for such purposes.

                                      -4-

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         7.       DENOMINATIONS, TRANSFER, EXCHANGE. The Notes are in registered
form without interest coupons in denominations of $1,000 and whole multiples of
$1,000. The transfer of Notes may be registered and Notes may be exchanged as
provided in the Indenture. The Registrar and the Trustee may require a Holder,
among other things, to furnish appropriate endorsements and transfer documents
and the Company may require a Holder to pay any taxes and fees required by law
or permitted by the Indenture. The Company need not exchange or register the
transfer of any Note or portion of a Note selected for redemption, except for
the unredeemed portion of any Note being redeemed in part. Also, the Company
need not exchange or register the transfer of any Notes for a period of 15 days
before the date on which a notice of redemption is mailed or during the period
between a record date and the corresponding Interest Payment Date.

         8.       PERSONS DEEMED OWNERS. The registered Holder of a Note may be
treated as its owner for all purposes.

         9.       AMENDMENT, SUPPLEMENT AND WAIVER. Subject to certain
exceptions, the Indenture and the Notes may be amended or supplemented with the
consent of the Holders of at least a majority in principal amount of the then
outstanding Notes (including consents obtained in connection with a purchase of,
or tender offer or exchange offer for, Notes), and any existing Default or Event
of Default (other than a Default or Event of Default in the payment of the
principal of, premium, if any, or interest, if any, on the Notes, except a
payment default resulting from an acceleration that has been rescinded) or
compliance with any provision of the Indenture or the Notes may be waived with
the consent of the Holders of a majority in principal amount of the then
outstanding Notes (including consent obtained in connection with a purchase of
or tender offer or exchange for Notes). Without the consent of any Holder of a
Note, the Indenture or the Notes may be amended or supplemented to cure any
ambiguity, defect or inconsistency, to provide for uncertificated Notes in
addition to or in place of certificated Notes, to provide for the assumption of
the Company's obligations to the Holders of the Notes in the case of a merger,
consolidation or sale of all or substantially all of the assets of the Company,
to make any change that would provide any additional rights or benefits to the
Holders of the Notes or that does not adversely affect the legal rights under
the Indenture of any such Holder, to comply with the requirements of the SEC in
order to effect or maintain the qualification of the Indenture under the TIA or
to provide for the issuance of Additional Notes.

         10.      DEFAULTS AND REMEDIES. Events of Default include: (i) default
which continues for 30 days in the payment when due of interest on the Notes;
(ii) default in payment when due of the principal of or premium, if any, on the
Notes; (iii) failure by the Company for 60 days after receipt of notice from the
Trustee or Holders of at least 25% in principal amount of the then outstanding
Notes to comply with any of its other agreements or obligations in the Indenture
or the Notes; (iv) Indebtedness of the Company (other than Indebtedness owed to
the Company or any Subsidiary), or any Indebtedness that is Guaranteed by the
Company, is not paid within any applicable grace period after final maturity or
is accelerated by the holders thereof because of a default (or similar event or
circumstance) and the total amount of such Indebtedness unpaid or accelerated
exceeds $1.0 million; provided, however, that in the case of any Indebtedness
that is accelerated, such acceleration has not been rescinded after 30 days'
written notice provided in accordance with the applicable indenture or other
debt instrument evidencing such Indebtedness; (v) failure by the Company to pay
final judgments for the payment of money (other than judgments that are covered
by enforceable insurance policies issued by reputable carriers and as to which
such insurance carriers have acknowledged liability in writing) aggregating in
excess of $1.0 million, which judgments are not paid, discharged, bonded or
stayed for a period of 60 days after notice thereof has been given by the
Trustee or Holders of at least 25% in principal amount of the then outstanding
Notes issued under the Indenture; and (vi) certain events of bankruptcy or
insolvency with respect to the Company or any Subsidiary or group of
Subsidiaries that, taken together, would constitute a Significant Subsidiary.
The Trustee must, within 90 days after the occurrence of a Default or Event of
Default, give to the Holders notice of all uncured Defaults or Events of Default
known to it; provided, however, that except in the case of a Default or Event of
Default in payment of any Note, the Trustee may withhold such notice if a
committee of its Responsible Officers in good faith determines that the
withholding of such notice is in the interest of the Holders and provided
further that the Holders of the Notes may not accelerate the maturity of the
Notes upon any Event of Default except in the case of an Event of Default
arising as the result of the bankruptcy, insolvency, receivership,
conservatorship or reorganization of the Company, any Significant Subsidiary
that is a bank or any group of Subsidiaries that are banks that, taken together,
would constitute a Significant Subsidiary. The Company is required to furnish
annually to the Trustee a certificate as to their compliance with the terms of
the Indenture.

                                      -5-

<PAGE>

         11.      TRUSTEE DEALINGS WITH COMPANY. The Trustee in its individual
or any other capacity may become the owner or pledgee of Notes and may otherwise
deal with the Company or any Affiliate of the Company, with the same rights it
would have if it were not Trustee.

         12.      NO RECOURSE AGAINST OTHERS. No past, present or future
director, officer, employee, incorporator or shareholder of the Company, as
such, shall have any liability for any obligations of the Company under the
Notes or the Indenture or for any claim based on, in respect of, or by reason
of, such obligations or their creation. Each Holder of Notes by accepting a Note
waives and releases all such liability. The waiver and release are part of the
consideration for issuance of the Notes.

         13.      AUTHENTICATION. This Note shall not be valid until
authenticated by the manual signature of the Trustee or an authenticating agent.

         14.      ABBREVIATIONS. Customary abbreviations may be used in the name
of a Holder or an assignee, such as: TEN COM (= tenants in common), TEN ENT (=
tenants by the entireties), JT TEN (= joint tenants with right of survivorship
and not as tenants in common), CUST (= custodian), and U/G/M/A (= Uniform Gifts
to Minors Act).

         15.      CUSIP NUMBERS. Pursuant to a recommendation promulgated by the
Committee on Uniform Security Identification Procedures, the Company has caused
CUSIP numbers to be printed on the Notes and the Trustee may use CUSIP numbers
in notices of redemption as a convenience to the Holders. No representation is
made as to the accuracy of such numbers either as printed on the Notes or as
contained in any notice of redemption and reliance may be placed only on the
other identification numbers placed thereon.

         16.      GOVERNING LAW. THE INTERNAL LAW OF THE STATE OF GEORGIA SHALL
GOVERN AND BE USED TO CONSTRUE THE INDENTURE AND THE NOTES WITHOUT GIVING EFFECT
TO CONFLICTS OF LAWS PRINCIPLES.

         17.      DEFINED TERMS. Capitalized terms used but not defined herein
have their respective defined meanings as set forth in the Indenture.

         18.      REQUEST FOR COPY OF INDENTURE. The Company shall furnish to
any Holder upon written request and without charge a copy of the Indenture.
Requests may be made to:

                  United Community Banks, Inc.
                  63 Highway 515
                  P.O. Box 398
                  Blairsville, GA  30514
                  Telephone:  (706) 781-2265
                  Facsimile:  (706) 745-8960
                  Attention:  Thomas C. Gilliland

                                      -6-

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                                 ASSIGNMENT FORM

         To assign this Note, fill in the form below:

(I) or (we) assign and transfer this Note to

________________________________________________________________________________
                  (Insert assignee's Soc. Sec. or tax I.D. no.)

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________
              (Print or type assignee's name, address and zip code)

and irrevocably appoint ____________________________________________________ to
transfer this Note on the books of the Company. The agent may substitute another
to act for him.

________________________________________________________________________________

Date:___________________

                          Your Signature:_______________________________________
                          (Sign exactly as your name appears on the face of this
                          Note)

                          Signature Guarantee(1):_______________________________

--------------------------------------
(1) Participant in a recognized Signature Guarantee Medallion Program (or other
signature guarantor acceptable to the Trustee).

                                      -7-

<PAGE>

                SCHEDULE OF EXCHANGES OF CERTIFICATED SECURITIES

     The following exchanges of a part of this Global Note for Certificated
                           Securities have been made:

<TABLE>
<CAPTION>
                                                                       Principal Amount
                              Amount of             Amount of                  of                 Signature
                             decrease  in          increase in           this Global Note        authorized
                           Principal Amount      Principal Amount         following such         signatory of
                                  of                  of                   decrease (or          Trustee or
Date of Exchange           this Global Note      this Global Note            increase)          Note Custodian
----------------           ----------------      ----------------            ---------          --------------
<S>                        <C>                   <C>                   <C>                      <C>
</TABLE>

                                      -8-