FOURTH AMENDED AND RESTATED LETTER OF CREDIT AND REIMBURSEMENT AGREEMENT

EXHIBIT 10(ll)

FOURTH AMENDED AND RESTATED

LETTER OF CREDIT AND REIMBURSEMENT AGREEMENT

dated as of

December 10, 2004

among

LINCOLN NATIONAL CORPORATION,

as an Account Party and Guarantor

The SUBSIDIARY ACCOUNT PARTIES,

as additional Account Parties

The BANKS Party Hereto

and

JPMORGAN CHASE BANK, N.A.,

as Administrative Agent

$900,000,000

J.P. MORGAN SECURITIES INC.

and

WACHOVIA CAPITAL MARKETS, LLC,

as Joint Lead Arrangers and Joint Bookrunners

WACHOVIA BANK, NATIONAL ASSOCIATION,

as Syndication Agent

THE BANK OF NEW YORK

and

CITIBANK, N.A.,

as Documentation Agents

FOURTH AMENDED AND RESTATED LETTER OF CREDIT AND REIMBURSEMENT AGREEMENT dated as of December 10, 2004 (this “ Fourth Amendment and Restatement ”) among LINCOLN NATIONAL CORPORATION, an Indiana corporation (together with its successors and permitted assigns, the “ Company ”), the SUBSIDIARY ACCOUNT PARTIES party hereto (the “ Subsidiary Account Parties ”), the BANKS party hereto (including each Person listed under the caption “BANKS” on the signature pages hereto that is not a “Bank” under the Existing LC Agreement referred to below (each a “ New Bank ”), the “ Banks ”) and JPMORGAN CHASE BANK, N.A. (formerly known as JPMorgan Chase Bank) (“ JPMCB ”), as administrative agent for the Banks (in such capacity, together with its successors in such capacity, the “ Administrative Agent ”).

W I T N E S S E T H :

WHEREAS, the Company, each Subsidiary Account Party, the banks party thereto (the “ Existing Banks ”) and JPMCB, as Administrative Agent, are parties to the Third Amended and Restated Letter of Credit and Reimbursement Agreement dated as of December 11, 2003 (as amended and in effect immediately prior to the satisfaction (or waiver) of the conditions set forth in Section 4 hereof, the “ Existing LC Agreement ”);

WHEREAS, each of the Existing Banks that is not listed under the caption “BANKS” on the signature pages hereto (collectively, the “ Retiring Banks ”) will cease being a “Bank” under the Existing LC Agreement as of the Restatement Effective Date (as defined in Section 4 hereof), and each of the New Banks wishes to become a “Bank” under the Existing LC Agreement as amended and restated by this Fourth Amendment and Restatement; and

WHEREAS, the Company has requested certain amendments to provisions of the Existing LC Agreement, including the extension of the availability of the commitments thereunder, and the Banks (including the New Banks) are willing to make such amendments on the terms and conditions set forth below;

NOW, THEREFORE, in consideration of the foregoing premises and the mutual agreements contained herein, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto hereby agree that, effective as of the Restatement Effective Date (as defined in Section 4 hereof), the Existing LC Agreement shall be amended and restated to read in its entirety as set forth in the Existing LC Agreement, which is incorporated herein by this reference, subject to the amendments set forth in Section 2 hereof (the Existing LC Agreement, as so amended and restated hereby, is herein called the “ Fourth Amended and Restated LC Agreement ”):

Section 1. Definitions . Except as otherwise defined herein, terms defined in the Existing LC Agreement have the meanings ascribed thereto in the Existing LC Agreement, after giving effect to the amendments set forth in Section 2 hereof.

Section 2. Amendments . Effective as of the Restatement Effective Date, the Existing LC Agreement is hereby amended as follows:

2.01. Certain References . References in the Existing LC Agreement to (i) “this Agreement” or words of similar import (including indirect references to the Existing LC Agreement) and in Exhibits A, B and C to the Existing LC Agreement to “the Third Amended

Fourth Amended and Restated Letter of Credit and Reimbursement Agreement

and Restated Letter of Credit and Reimbursement Agreement dated as of December 11, 2003” shall be deemed to be references to the Fourth Amended and Restated LC Agreement, (ii) “Schedule I” and “Schedule II” or words of similar import (including indirect references to such schedule) shall be deemed to be references to Schedule I and Schedule II, respectively, to this Fourth Amendment and Restatement and (iii) “Effective Date” (other than in Exhibits A and C thereto) shall be deemed to be references to the Restatement Effective Date.

2.02. Recitals . The recitals in the Existing LC Agreement shall be amended and restated in their entirety to read as follows: “The parties hereto agree as follows:”.

2.03. Certain Definitions .

(a) The last sentence of the definition of “ Commitment ” contained in Section 1.01 of the Existing LC Agreement shall be amended in its entirety to read as follows: “The aggregate amount of the Banks’ Commitments is $900,000,000 as of the Restatement Effective Date.”

(b) Section 1.01 of the Existing LC Agreement shall be amended by inserting the following definitions (or, in the case of any of the following defined terms that are already defined in the Existing LC Agreement, by amending and restating in its entirety each such term to read as set forth below) in their proper respective alphabetical locations:

“ Applicable Rate ” means, for any day, with respect to the facility fees or letter of credit fees payable hereunder, as the case may be, the applicable rate per annum set forth below under the caption “Facility Fee” or “Letter of Credit Fee”, respectively, based upon the ratings by Moody’s and S&P, respectively, applicable on such date to the Index Debt:

For purposes of the foregoing, (a) if the ratings established or deemed to have been established by Moody’s and S&P for the Index Debt shall fall within different Categories that are one Category apart, the Applicable Rate shall be determined by reference to the Category of the higher of the two ratings; (b) if the ratings established or deemed to have been established by Moody’s and S&P for the Index Debt shall fall within different Categories that are more than one

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Category apart, the Applicable Rate shall be determined by reference to the Category next below that of the higher of the two ratings; (c) if only one of Moody’s and S&P shall have in effect a rating for the Index Debt, the Applicable Rate shall be determined by reference to the Category of such rating; (d) if neither Moody’s nor S&P shall have in effect a rating for the Index Debt (other than by reason of the circumstances referred to in the last sentence of this definition), then the applicable rating shall be determined by reference to Category 4; and (e) if the ratings established or deemed to have been established by Moody’s and S&P for the Index Debt shall be changed (other than as a result of a change in the rating system of Moody’s or S&P), such change shall be effective as of the date on which it is first announced by the applicable rating agency, irrespective of when notice of such change shall have been furnished by the Company to the Administrative Agent and the Banks pursuant to Section 5.01 or otherwise. Each change in the Applicable Rate shall apply during the period commencing on the effective date of such change and ending on the date immediately preceding the effective date of the next such change. If the rating system of Moody’s or S&P shall change, or if either such rating agency shall cease to be in the business of rating corporate debt obligations, the Company and the Banks shall negotiate in good faith to amend this definition to reflect such changed rating system or the unavailability of ratings from such rating agency and, pending the effectiveness of any such amendment, the Applicable Rate shall be determined by reference to the rating of Moody’s and/or S&P, as the case may be, most recently in effect prior to such change or cessation.

“ Commitment Termination Date ” means December 10, 2009 or, if such day is not a Business Day, the next preceding Business Day.

“ Company’s 2003 Form 10-K ” means the Company’s annual report on Form 10-K for 2003, as filed with the Securities and Exchange Commission pursuant to the Securities Exchange Act of 1934, as amended.

“ JPMCB ” means JPMorgan Chase Bank, N.A. (formerly known as JPMorgan Chase Bank).

“ Restatement Effective Date ” has the meaning set forth in Section 4 of the Fourth Amended and Restated Letter of Credit and Reimbursement Agreement dated as of December 10, 2004.

(c) The definition of “Effective Date” contained in Section 1.01 of the Existing LC Agreement shall be deleted in its entirety.

(d) The definition of “Existing LC Agreement” contained in Section 1.01 of the Existing LC Agreement shall be deleted in its entirety.

(e) Each reference to the term “Company’s 2002 Form 10-K” in the Existing LC Agreement shall be amended and replaced with the term “Company’s 2003 Form 10-K”.

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2.04. Expiry Date of Letters of Credit . Section 2.01(d) of the Existing LC Agreement shall be amended and restated in its entirety as follows:

“(d) Expiry Date . Each Committed Letter of Credit shall expire at or prior to the close of business on the earlier of (i) the date one year after the date of the issuance of such Letter of Credit ( provided that such Committed Letter of Credit may contain “evergreen” provisions for the renewal or extension thereof to a date one year after the then current expiry date thereof) or (ii) December 31, 2010.”

2.05. Existing Letters of Credit . Section 2.01(h) of the Existing LC Agreement shall be deleted in its entirety.

2.06. Alternative Currency Letters of Credit . The seventh and eighth sentences of Section 2.03(e) of the Existing LC Agreement shall be amended and restated in their entirety as follows:

“At any time, and from time to time, while an Event of Default has occurred and is continuing, the Administrative Agent shall, if instructed by the Required Banks in their sole discretion, liquidate any such investments and reinvestments and credit the proceeds thereof to the Collateral Account and apply or cause to be applied such proceeds and any other balances in the Collateral Account to the payment of any of the Secured Obligations due and payable. If at any time (i) no Default has occurred and is continuing and (ii) all of the Secured Obligations then due have been paid in full but Committed Letters of Credit remain outstanding, the Administrative Agent shall, from time to time, at the request of the Company, deliver to the Company, against receipt but without any recourse, warranty or representation whatsoever, such of the balances in the Collateral Account as exceed the aggregate undrawn face amount of all outstanding Committed Letters of Credit.”

2.07. Increase of the Commitments . Section 2.04(e) of the Existing LC Agreement shall be amended by deleting the amount “$800,000,000” in the third line thereof and replacing it with the amount “$1,000,000,000”.

2.08. Facility Fees . Section 2.05(a) of the Existing LC Agreement shall be amended and restated in its entirety as follows:

“(a) The Company agrees to pay to the Administrative Agent for account of each Bank a facility fee, which shall accrue at the Applicable Rate, (i) prior to the termination of such Bank’s Commitment, on the daily amount of the Commitment of such Bank (whether used or unused) during the period from and including the Restatement Effective Date to but excluding the date that the Commitments terminate and (ii) if such Bank continues to have any LC Exposure after its Commitment terminates, on the daily amount of such Bank’s LC Exposure from and including the date its Commitment terminates to but excluding the date such Bank ceases to have any LC Exposure. Accrued facility fees shall be payable on each Quarterly Date and (if the Commitments shall have terminated) on the date the Banks cease to have any LC Exposure, commencing on the first such date after the Restatement Effective Date; provided that any facility fee accruing after the earlier of the date the Commitments terminate or the Commitment Termination Date shall be payable on demand at any time a Default has occurred and is continuing. Facility fees shall be computed on the basis of a year of 360 days and shall be payable for the