GUARANTEE AGREEMENT

Exhibit 10.2

EXECUTION COPY

GUARANTEE AGREEMENT

dated as of

March 13, 2007

among

LEVEL 3 COMMUNICATIONS, INC.,

the Subsidiaries of LEVEL 3 COMMUNICATIONS, INC. identified herein,

and

MERRILL LYNCH CAPITAL CORPORATION,

as Agent

TABLE OF CONTENTS

Schedule I – Subsidiary Guarantors

Exhibit A – Form of Supplement

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GUARANTEE AGREEMENT dated as of March 13, 2007 (this “ Agreement ”), among LEVEL 3 COMMUNICATIONS, INC., a Delaware corporation (“ Level 3 ”), the Subsidiary Guarantors identified herein and MERRILL LYNCH CAPITAL CORPORATION, as administrative agent and collateral agent (in such capacity, the “ Agent ”).

PRELIMINARY STATEMENT

Reference is made to the Credit Agreement dated as of March 13, 2007 (as amended, supplemented or otherwise modified from time to time, the “ Credit Agreement ”), among Level 3 Financing, Inc. (the “ Borrower ”), Level 3, the lenders from time to time party thereto (the “ Lenders ”) and the Agent. The Lenders have agreed to extend credit to the Borrower pursuant to and upon the terms and conditions specified in the Credit Agreement. The obligations of the Lenders to extend such credit to the Borrower are conditioned upon, among other things, the execution and delivery of this Agreement by Level 3 and the Subsidiary Guarantors. Level 3 and the Subsidiary Guarantors are affiliates of the Borrower, will derive substantial direct and indirect benefits from the extension of credit to the Borrower pursuant to the Credit Agreement and are willing to execute and deliver this Agreement in order to induce the Lenders to extend such credit.

Accordingly, the parties hereto agree as follows:

ARTICLE I

Definitions

SECTION 1.01. Credit Agreement . (a) Capitalized terms used in this Agreement (including the preamble and preliminary statement hereto) and not otherwise defined herein have the meanings set forth in the Credit Agreement.

(b) The rules of construction specified in Section 1.02 of the Credit Agreement also apply to this Agreement.

SECTION 1.02. Other Defined Terms . As used in this Agreement, the following terms have the meanings specified below:

“ Borrower ” has the meaning assigned to such term in the preliminary statement of this Agreement.

“ Agent ” has the meaning assigned to such term in the preamble of this Agreement.

“ Agreement ” has the meaning assigned to such term in the preamble hereto.

“ Credit Agreement ” has the meaning assigned to such term in the preliminary statement of this Agreement.

“ Guarantors ” means Level 3 and the Subsidiary Guarantors.

“ Obligations ” has the meaning assigned to such term in the Credit Agreement.

“ Secured Parties ” means (a) the Lenders, (b) the Agent, (c) each counterparty to any Specified Hedging Agreement the obligations under which constitute Obligations, (d) the beneficiaries of each indemnification obligation undertaken by any Loan Party under any Loan Document and (e) the successors and assigns of each of the foregoing.

“ Subsidiary Guarantors ” means (a) the Subsidiaries identified on Schedule I and (b) each other Subsidiary of Level 3 that becomes a party to this Agreement as a Subsidiary Guarantor pursuant to Section 3.14 after the Effective Date.

ARTICLE II

Guarantee

SECTION 2.01. Guarantee. Each Guarantor irrevocably and unconditionally guarantees, jointly with the other Guarantors and severally, as a primary obligor and not merely as a surety, the due and punctual payment and performance of the Obligations. Each of the Guarantors further agrees that the Obligations may be extended or renewed, in whole or in part, without notice to or further assent from it, and that it will remain bound upon its guarantee hereunder notwithstanding any such extension or renewal of any Obligation. Each of the Guarantors waives presentment to, demand of payment from and protest to the Borrower or any other Loan Party of any of the Obligations, and also waives notice of acceptance of its guarantee and notice of protest for nonpayment.

SECTION 2.02. Guarantee of Payment; Continuing Guarantee. Each of the Guarantors further agrees that its guarantee hereunder constitutes a guarantee of payment when due (whether or not any bankruptcy or similar proceeding shall have stayed the accrual or collection of any of the Obligations or operated as discharge thereof) and not merely of collection, and waives any right to require that any resort be had by the Agent or any other Secured Party to any security held for the payment of the Obligations or to any balance of any deposit account or credit on the books of the Agent or any other Secured Party in favor of the Borrower, any other Loan Party or any other Person. Each of the Guarantors agrees that its guarantee is continuing in nature and applies to all Obligations, whether currently existing or hereafter incurred.

SECTION 2.03. No Limitations, Etc. (a) Except for termination of a Guarantor’s obligations hereunder as expressly provided in Section 3.13, the obligations of each Guarantor hereunder shall not be subject to any reduction, limitation, impairment or termination for any reason, including any claim of waiver, release, surrender, alteration

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or compromise, and shall not be subject to any defense or setoff, counterclaim, recoupment or termination whatsoever by reason of the invalidity, illegality or unenforceability of the Obligations, any impossibility in the performance of the Obligations or otherwise. Without limiting the generality of the foregoing, the obligations of each Guarantor hereunder shall not be discharged or impaired or otherwise affected by (i) the failure of the Agent or any other Secured Party to assert any claim or demand or to enforce any right or remedy under the provisions of any Loan Document or otherwise; (ii) any extension or renewal of any of the Obligations, (iii) any rescission, waiver, amendment or modification of, or any release from any of the terms or provisions of, any Loan Document or any other agreement, including with respect to any other Guarantor under this Agreement; (iv) the release of, or any impairment of or failure to perfect any Lien on or security interest in any security held by the Agent or any other Secured Party for the Obligations or any of them; (v) any default, failure or delay, willful or otherwise, in the performance of the Obligations; or (vi) any other act, omission or delay to do any other act which may or might in any manner or to any extent vary the risk of any Guarantor or otherwise operate as a discharge of any Guarantor as a matter of law or equity (other than the indefeasible payment in full in cash of all the Obligations) or which would impair or eliminate the right of any Guarantor to subrogation. Each Guarantor expressly authorizes the Agent to take and hold security for the payment and performance of the Obligations, to exchange, waive or release any or all such security (with or without consideration), to enforce or apply such security and direct the order and manner of any sale thereof in its sole discretion or to release or substitute any one or more other guarantors or obligors upon or in respect of the Obligations, all without affecting the obligations of any Guarantor hereunder.

( b) To the fullest extent permitted by applicable law, each Guarantor waives any defense based on or arising out of any defense of the Borrower or any other Loan Party or the unenforceability of the Obligations or any part thereof from any cause, or the cessation from any cause of the liability of the Borrower or any other Loan Party, other than the indefeasible payment in full in cash of all the Obligations. The Agent and the other Secured Parties may, at their election, foreclose on any security held by one or more of them by one or more judicial or nonjudicial sales, accept an assignment of any such security in lieu of foreclosure, compromise or adjust any part of the Obligations, make any other accommodation with the Borrower or any other Loan Party or exercise any other right or remedy available to them against the Borrower or any other Loan Party, without affecting or impairing in any way the liability of any Guarantor hereunder except to the extent the Obligations have been fully and indefeasibly paid in full in cash. To the fullest extent permitted by applicable law, each Guarantor waives any defense arising out of any such election even though such election operates, pursuant to applicable law, to impair or to extinguish any right of reimbursement or subrogation or other right or remedy of such Guarantor against the Borrower or any other Loan Party, as the case may be, or any security.

SECTION 2.04. Reinstatement. Each of the Guarantors agrees that its guarantee hereunder shall continue to be effective or be reinstated, as the case may be, if at any time payment, or any part thereof, of any Obligation is rescinded or must otherwise be restored by the Agent or any other Secured Party upon the bankruptcy or reorganization of the Borrower, any other Loan Party or otherwise.

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SECTION 2.05. Agreement to Pay; Subrogation. In furtherance of the foregoing and not in limitation of any other right that the Agent or any other Secured Party may have at law or in equity against any Guarantor by virtue hereof, upon the failure of the Borrower or any other Loan Party to pay any Obligation when and as the same shall become due, whether at maturity, by acceleration, after notice of prepayment or otherwise, each Guarantor hereby promises to and will forthwith pay, or cause to be paid, to the Agent for distribution to the applicable Secured Parties in cash the amount of such unpaid Obligation. Upon payment by any Guarantor of any sums to the Agent as provided above, all rights of such Guarantor against the Borrower or any other Guarantor arising as a result thereof by way of right of subrogation, contribution, reimbursement, indemnity or otherwise shall in all respects be subordinate and junior in right of payment to the prior indefeasible payment in full in cash of all the Obligations. In addition, any indebtedness of the Borrower now or hereafter held by any Guarantor is hereby subordinated in right of payment to the prior indefeasible payment in full of the Obligations. If any amount shall erroneously be paid to any Guarantor on account of (i) such subrogation, contribution, reimbursement, indemnity or similar right or (ii) any such indebtedness of the Borrower, such amount shall be held in trust for the benefit of the Secured Parties and shall forthwith be paid to the Agent to be credited against the payment of the Obligations, whether matured or unmatured, in accordance with the terms of the Loan Documents.

SECTION 2.06. Information. Each Guarantor assumes all responsibility for being and keeping itself informed of the Borrower’s and each other Loan Party’s financial condition and assets, and of all other circumstances bearing upon the risk of nonpayment of the Obligations and the nature, scope and extent of the risks that such Guarantor assumes and incurs hereunder, and agrees that none of the Agent or the other Secured Parties will have any duty to advise such Guarantor of information known to it or any of them regarding such circumstances or risks.

SECTION 2.07. Taxes. Each of the Guarantors agrees that the provisions of Section 2.11 of the Credit Agreement shall apply equally to such Guarantor with respect to payments made by it hereunder.

SECTION 2.08. Representations and Warranties. Each of the Guarantors represents and warrants as to itself that all representations and warranties relating to it contained in the Credit Agreement are true and correct.

ARTICLE III

Miscellaneous

SECTION 3.01. Notices . All communications and notices hereunder shall (except as otherwise expressly permitted herein) be in writing and given as provided in Section 9.01 of the Credit Agreement. All communications and notices hereunder to any Subsidiary Guarantor shall be