EXHIBIT (4)

THIS NOTE IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITORY OR A NOMINEE THEREOF. UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR NOTES IN CERTIFICATED FORM, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), TO A NOMINEE OF DTC OR BY DTC OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITORY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITORY. UNLESS THIS NOTE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF DTC TO MERRILL LYNCH & CO., INC. OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY NOTE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT 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.

MERRILL LYNCH & CO., INC.

Principal Protected Averaging Notes Linked to the S&P 500 Index

due July 15, 2011

(the “Notes”)

Merrill Lynch & Co., Inc., a Delaware corporation (hereinafter referred to as the “Company”, which term includes any successor corporation under the Indenture herein referred to), for value received, hereby promises to pay to CEDE & CO., or its registered assigns, an amount for each Unit equal to the principal amount plus the Supplemental Redemption Amount, if any, as defined below, on July 15, 2011 (the “Stated Maturity”).

Payment or delivery of the principal amount, the Supplemental Redemption Amount, if any, and any interest on any overdue amount thereof with respect to this Note shall be made at the office or agency of the Company maintained for that purpose in the Borough of Manhattan, The City of New York, 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.

This Note is one of the series of Principal Protected Averaging Notes Linked to the S&P 500 Index due July 15, 2011.

Payment at Maturity

The “Supplemental Redemption Amount” with respect to each Unit of this Note shall be determined by the Calculation Agent (as defined below) as described below:

provided, however, that in no event will the Supplemental Redemption Amount be less than zero.

The “Participation Rate” equals 175%. The “Starting Value” equals 1,133.35. The “Ending Value” shall be determined by Merrill Lynch, Pierce, Fenner & Smith Incorporated (the “Calculation Agent”) and shall equal the average (arithmetic mean) of the closing values of the S&P 500 Index determined at the close of the market on each Valuation Date (as defined below).

“Valuation Date” means the 28^th of each March, June, September and December, beginning September 28, 2004 and ending on June 28, 2011. If a Valuation Date falls on a day that is not an Index Business Day, that Valuation Date will be the next succeeding Index Business Day; provided, however, if the closing value for the final Valuation Date has not been determined by the second scheduled Index Business Day prior to the stated maturity date, then the closing value for the final Valuation Date shall be the closing value of the Index on such day, regardless of the occurrence of a Market Disruption Event on such day.

An “Index Business Day” means a day on which the Nasdaq Stock Market, The New York Stock Exchange (the “NYSE”), and the American Stock Exchange (the “AMEX”) are open for trading and (i) the S&P 500 Index or any Successor Index (as defined below) is calculated and published and (ii) a Market Disruption Event (as defined below) has not occurred.

All determinations made by the Calculation Agent shall be at the sole discretion of the Calculation Agent and, absent a determination of a manifest error, shall be conclusive for all purposes and binding on the Company and the Holders and beneficial owners of the Notes.

Adjustments to the S&P 500 Index; Market Disruption Events

If at any time Standard & Poor’s (“S&P”) makes a material change in the formula for or the method of calculating the S&P 500 Index or in any other way materially modifies the S&P 500 Index so that the S&P 500 Index does not, in the opinion of the Calculation Agent, fairly represent the value of the S&P 500 Index had those changes or modifications not been made, then, from and after that time, the Calculation Agent shall, at the close of business in New York, New York, on each date that the closing value of the S&P 500 Index is to be calculated, make any adjustments as, in the good faith judgment of the Calculation Agent, may be necessary in order to arrive at a calculation of a value of a stock index comparable to the S&P 500 Index as if those changes or modifications had not been made, and calculate the closing value with reference to the S&P 500 Index, as so adjusted. Accordingly, if the method of calculating the S&P 500 Index is modified so that the value of the S&P 500 Index is a fraction or a multiple of what it would have been if it had not been modified, e.g., due to a split, then the Calculation Agent shall adjust the S&P 500 Index in order to arrive at a value of the S&P 500 Index as if it had not been modified, e.g., as if the split had not occurred.

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“Market Disruption Event” means either of the following events, as determined by the Calculation Agent:

For the purpose of the above definition:

Discontinuance of the S&P 500 Index

If S&P discontinues publication of the S&P 500 Index and S&P or another entity publishes a successor or substitute index that the Calculation Agent determines, in its sole discretion, to be comparable to the S&P 500 Index (a “Successor Index”), then, upon the Calculation Agent’s notification of its determination to the Trustee (as defined below) and the Company, the Calculation Agent shall substitute the Successor Index as calculated by S&P or any other entity for the S&P 500 Index and calculate the Ending Value as described above under “Payment at Maturity”. Upon any selection by the Calculation Agent of a Successor Index, the Company shall cause notice to be given to Holders of the Notes.

In the event that S&P discontinues publication of the S&P 500 Index and:

the Calculation Agent shall compute a substitute value for the S&P 500 Index in accordance with the procedures last used to calculate the S&P 500 Index before any discontinuance. If a Successor Index is selected or the Calculation Agent calculates a value as a substitute for the

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S&P 500 Index as described below, the Successor Index or value shall be used as a substitute for the S&P 500 Index for all purposes, including for purposes of determining whether a Market Disruption Event exists.

If S&P discontinues publication of the S&P 500 Index before the determination of the Ending Value and the Calculation Agent determines that no Successor Index is available at that time, then on each Business Day until the earlier to occur of:

the Calculation Agent shall determine the value that would be used in computing the Supplemental Redemption Amount as described in the preceding paragraph. The Calculation Agent shall cause notice of each value to be published not less often than once each month in The Wall Street Journal or another newspaper of general circulation, and arrange for information with respect to these values to be made available by telephone.

A “Business Day” means a day on which the NYSE, The Nasdaq Stock Market and the AMEX are open for trading.

General

This Note is one of a duly authorized issue of Securities of the Company, issued and to be issued under an Indenture, dated as of April 1, 1983, as amended and restated (herein referred to as the “Indenture”), between the Company and JPMorgan Chase Bank, as Trustee (herein referred to as the “Trustee”, which term includes any successor Trustee under the Indenture), to which Indenture and all indentures supplemental thereto reference is hereby made for a statement of the respective rights thereunder of the Company, the Trustee and the Holders of the Notes, and the terms upon which the Notes are, and are to be, authenticated and delivered.

The Company hereby covenants for the benefit of the Holders of the Notes, to the extent permitted by applicable law, not to claim voluntarily the benefits of any laws concerning usurious rates of interest against a Holder of the Notes.

The Notes are not subject to redemption by the Company prior to the Stated Maturity.

In case an Event of Default with respect to any Notes shall have occurred and be continuing, the amount payable to a Holder of a Note upon any acceleration permitted by the Notes, with respect to each Unit, shall be equal to the principal amount and the Supplemental Redemption Amount, if any, calculated as though the date of early repayment were the Stated Maturity of the Notes.

In case of default in payment of the Notes (whether at the Stated Maturity or upon acceleration), from and after such date of default the Notes shall bear interest, payable upon demand of the Holders thereof, at the rate of 1.25% per annum (to the extent that payment of such interest shall be legally enforceable) on the unpaid amount due and payable on such date in accordance with the terms of the Notes to the date payment of such amount has been made or duly provided for.

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The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modification of the rights and obligations of the Company and the rights of the Holders of the Securities of each series to be affected under the Indenture at any time by the Company and the Trustee with the consent of the Holders of not less than 66  ²/3% in aggregate original public offering price or principal amount, as the case may be of the Securities at the time Outstanding of each series affected thereby. Holders of specified percentages in aggregate original public offering price or principal amount, as the case may be, of the Securities of each series at the time Outstanding, on behalf of the Holders of all Securities of each series, are permitted to waive compliance by the Company with certain provisions of the Indenture and certain past defaults under the Indenture and their consequences. Any such consent or waiver by the Holder of this Note shall be conclusive and binding upon such Holder and upon all future Holders of this Note and of any Note issued upon the registration of transfer hereof or in exchange herefor or in lieu hereof whether or not notation of such consent or waiver is made upon this Note.

No reference herein to the Indenture and no provision of this Note or of the Indenture shall alter or impair the obligation of the Company, which is absolute and unconditional, to pay the principal amount hereof, the Supplemental Redemption Amount, if any, with respect to this Note and any interest on any overdue amount thereof at the time, place, and rate, and in the coin or currency herein prescribed.

As provided in the Indenture and subject to certain limitations set forth therein and on the first page hereof, the transfer of this Note may be registered on the Security Register of the Company, upon surrender of this Note for registration of transfer at the office or agency of the Company in the Borough of Manhattan, The City of New York, duly endorsed by, or accompanied by a written instrument of transfer in form satisfactory to the Company duly executed by, the Holder hereof or by his attorney duly authorized in writing, and thereupon one or more new Notes, of authorized denominations and for the same aggregate original public offering price, shall be issued to the designated transferee or transferees.

The Notes are issuable only in registered form without coupons in denominations of a single Unit and integral multiples thereof. This Note shall remain in the form of a global security held by a Depository. Notwithstanding the foregoing, if (x) any Depository is at any time unwilling or unable to continue as Depository and a successor depository is not appointed by the Company within 60 days, (y) the Company executes and delivers to the Trustee a Company Order to the effect that this Note shall be exchangeable or (z) an Event of Default has occurred and is continuing with respect to the Notes, this Note shall be exchangeable for Notes in definitive form of like tenor and of an equal aggregate original public offering price, in denominations of a single Unit and integral multiples thereof. Such definitive Notes shall be registered in such name or names as the Depository shall instruct the Trustee. If definitive Notes are so delivered, the Company may make such changes to the form of this Note as are necessary or appropriate to allow for the issuance of such definitive Notes.

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No service charge shall be made for any such registration of transfer or exchange, but the Company may require payment of a sum sufficient to cover any tax or governmental charge payable in connection therewith.

Prior to due presentment of this Note for registration of transfer, the Company, the Trustee and any agent of the Company or the Trustee may treat the Person in whose name this Note is registered as the owner hereof for all purposes, whether or not this Note be overdue, and neither the Company, the Trustee nor any such agent shall be affected by notice to the contrary.

All terms used in this Note which are defined in the Indenture but not in this Note shall have the meanings assigned to them in the Indenture.

Unless the certificate of authentication hereon has been executed by JPMorgan Chase Bank, the Trustee under the Indenture, or its successor thereunder, by the manual signature of one of its authorized officers, this Note shall not be entitled to any benefits under the Indenture or be valid or obligatory for any purpose.

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IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed under its corporate seal.

Dated: July 15, 2004

[Copy of Seal]

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