FIFTEENTH AMENDMENT TO TRUST AGREEMENT BETWEEN HAWAIIAN ELECTRIC INDUSTRIES, INC., AMERICAN SAVINGS BANK, F.S.B. AND FIDELITY MANAGEMENT TRUST COMPANY

HEI Exhibit 4.6(p)

FIFTEENTH AMENDMENT TO TRUST AGREEMENT BETWEEN

HAWAIIAN ELECTRIC INDUSTRIES, INC., AMERICAN SAVINGS BANK, F.S.B. AND

FIDELITY MANAGEMENT TRUST COMPANY

THIS FIFTEENTH AMENDMENT TO TRUST AGREEMENT is made and entered into effective January 15, 2010, and is effective on that date unless otherwise stated herein, by and between Fidelity Management Trust Company (the “Trustee”) and Hawaiian Electric Industries, Inc. and American Savings Bank, F.S.B. (collectively and individually, the “Sponsor”);

WITNESSETH:

WHEREAS, the Trustee and the Sponsor heretofore entered into a Trust Agreement dated February 1, 2000, and amended August 1, 2000, November 1, 2000, April 1, 2001, December 31, 2001, January 1, 2002, April 1, 2002, July 1, 2002, September 1, 2003, February 2, 2004, October 3, 2005, November 1, 2006, August 1, 2007, October 17, 2008, and December 31, 2008 and further amended by letters of direction executed by the Sponsor and the Trustee which specifically state that both parties intend and agree that the direction letter shall constitute an amendment (the “Trust Agreement”) for the Hawaiian Electric Industries Retirement Savings Plan and American Savings Bank 401(k) Plan (collectively and individually, the “Plan”); and

WHEREAS, the Sponsor desires that the Hawaiian Electric Industries Retirement Savings Plan and American Savings Bank 401(k) Plan maintain separate employer stock funds and as a result hereby directs the Trustee that effective after the close of business on January 15, 2010, the HEI Common Stock Fund will be removed from the American Savings Bank 401(k) Plan and the HEI Common Stock Fund #2 will be added to the American Savings Bank 401(k) Plan; and

WHEREAS, the Sponsor now desires, and hereby directs the Trustee, in accordance with Sections 4(b) and 7(b), effective after the close of business on January 15, 2010, for the American Savings Bank 401(k) Plan only (1) to redirect all participant contributions directed to the HEI Common Stock Fund to be invested in the HEI Common Stock Fund #2 and (2) to transfer in-kind all participant balances held in the HEI Common Stock Fund to the HEI Common Stock Fund #2. The parties hereto agree that the Trustee shall have no discretionary authority with respect to this redirection and conversion directed by the Sponsor. Any variation from the procedure described herein may be instituted only at the express written direction of the Sponsor; and

WHEREAS, in furtherance of the foregoing, the Sponsor and the Trustee desire to amend said Trust Agreement as provided for in Section 13 thereunder;

NOW THEREFORE, in consideration of the above premises, the Sponsor and the Trustee hereby amend the Trust Agreement by:

IN WITNESS WHEREOF, the Trustee and the Sponsor have caused this Fifteenth Amendment to be executed by their duly authorized officers effective as of the day and year first above written. By signing below, the undersigned represent that they are authorized to execute this document on behalf of the respective parties. Notwithstanding any contradictory provision of the agreement that this document amends, each party may rely without duty of inquiry on the foregoing representation.

Schedule “A”

ADMINISTRATIVE SERVICES

The Trustee will provide the recordkeeping and administrative services set forth on this Schedule “A”, or as otherwise agreed to in writing (or by means of a secure electronic medium) between the Sponsor and Trustee in accordance with direction procedures established by the Trustee with the written approval of the Sponsor and documented in the Plan Administration Manual. With regard to Plan specific services, the Trustee shall add services only at the direction of the Sponsor. With prior written notice to the Sponsor, the Trustee may unilaterally enhance the services previously approved, provided there is no impact on fees set forth in Schedule “B”; and further provided that if the Sponsor notifies the Trustee in writing that a change to a previously approved service proposed by the Trustee pursuant to this sentence is unacceptable to the Sponsor, such service change shall not be applied.

Administration

Processing

Other

Financial Reporting

Account Segregation

Internet Services

Processing Services

Miscellaneous Services

Schedule “C”

INVESTMENT OPTIONS

In accordance with Section 4(b), the PIC hereby directs the Trustee that participants’ individual accounts may be invested in the following investment options:

The PIC hereby acknowledges that it has received from the Trustee via regular mail a paper copy of the prospectus for each Fidelity Class K Mutual Fund selected by the PIC as a Plan investment option. The PIC understands that the Fidelity Class K Mutual Fund prospectus(es) are not available at this time online at www.fidelity.com. Participants or beneficiaries who wish to invest in a Fidelity Class K Mutual Fund will be provided with a Fidelity Class K Mutual Fund prospectus, via regular mail, prior to such investment.

The PIC hereby directs that for Plan assets allocated to a participant’s account, the investment option referred to in Section 4(c) shall be the Fidelity Freedom Fund determined according to a methodology selected by the PIC and communicated to the Trustee in writing. In the case of unallocated Plan assets, Plan assets received from the termination or reallocation of an investment option, or Plan assets described in Section 4(d)(vi)(B)(5), the Plan’s default investment shall be the ASB Money Market Account.

The PIC hereby directs the Trustee to update the methodology (i.e., date ranges) as additional Fidelity Freedom Funds^® are launched and added in accordance with the preceding paragraph. Such updates will be made to the service as soon as administratively feasible following the launch of future Fidelity Freedom Funds^®, unless otherwise directed by the PIC. The PIC hereby directs the Trustee to add any additional Fidelity Freedom Funds^® as permissible investment options as they are launched, such funds being available to Plan participants as of the open of trading on the New York Stock Exchange on their respective inception dates or as soon thereafter as administratively possible, unless otherwise directed by the PIC.