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                                                                     Exhibit 4.3
                               FORM OF GUARANTEE


     GUARANTEE, dated as of __________, 200__, of AGL Resources Inc., a Georgia
corporation (the "Guarantor").

     The Guarantor, for value received, hereby unconditionally guarantees to
each Holder of a Security authenticated and delivered by the Trustee, and to the
Trustee on behalf of each such Holder, the due and punctual payment of the
principal of (and premium, if any) and interest, if any, on each such Security,
the due and punctual payment of any sinking fund payments and the payment of any
additional amounts, each as provided for pursuant to the terms of such Security
when and as the same shall become due and payable, in accordance with the terms
of such Security and of the Indenture dated ____________, 2000 by and among the
Guarantor, AGL Capital Corporation and The Bank of New York, as Trustee (the
"Indenture"). In case of the failure of the Company to make any such payment of
principal (or premium, if any) or interest, if any, or sinking fund payment or
payment of additional amounts, the Guarantor hereby agrees to cause any such
payment to be made when and as the same shall become due and payable by
acceleration, call for redemption or otherwise, as if such payment were made by
the Company.

     The Guarantor hereby agrees that its obligations hereunder shall be
unconditional, irrespective of the validity, regularity or enforceability of
such Security or the Indenture, the absence of any action to enforce the same,
any waiver or consent by the Holder of such Security or by the Trustee with
respect to any provisions thereof or of the Indenture, the obtaining of any
judgment against the Company or any action to enforce the same or any other
circumstances which might otherwise constitute a legal or equitable discharge or
defense of a guarantor.  The Guarantor hereby waives the benefits of division
and discussion, diligence, presentment, demand of payment, filing of claims with
a court in the event of insolvency or bankruptcy of the Company, any right to
require a proceeding first against the Company, protest or notice with respect
to such Security or the indebtedness evidenced thereby or with respect to any
sinking fund payment required pursuant to the terms of such Security and all
demands whatsoever, and covenants that this Guarantee will not be discharged
except by complete performance of the obligations contained in the Securities
and in the Guarantees.  The Guarantees are guarantees of payment and not of
collection.  If the Trustee or the Holder of any Security is required by any
court or otherwise to return to the Company or the Guarantor, or any custodian,
receiver, liquidator, trustee, sequestrator or other similar official acting in
relation to the Company or the Guarantor, any amount paid to the Trustee or such
Holder in respect of a Security, this Guarantee, to the extent theretofore
discharged, shall be reinstated in full force and effect.

     The Guarantor shall be subrogated to all rights of the Holders of the
Securities of a particular series against the Company in respect of any amounts
paid by the Guarantor on account or such Security pursuant to the provisions of
the Guarantees or the Indenture; provided, however, that the Guarantor shall
not be entitled to enforce or to receive any payments arising out of, or based
upon, such right of subrogation until the principal of (and premium, if any) and
interest, if any, on all Securities of such series issued hereunder shall have
been paid in full.
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     Capitalized terms used herein have the same meanings given in the Indenture
unless otherwise indicated.  This Guarantee shall be governed by and construed
in accordance with the law of the State of  New York.

                                     AGL RESOURCES INC.


                                     _________________________
                                     By: Donald P. Weinstein
                                     Title: Chief Financial Officer