Alcoa and subsidiaries EXHIBIT 15

October 23, 2003

Securities and Exchange Commission

450 Fifth Street, N.W.

Washington, D.C. 20549

RE: Alcoa Inc.

1. Forms S-8 (Registration Nos. 33-24846, 333-32516, 333-106411, 333-91331 and 333-36214) Alcoa Savings Plan for Salaried Employees; Alcoa Savings Plan for Bargaining Employees; Alcoa Savings Plan for Non-Bargaining Employees; Alcoa Savings Plan for Subsidiary and Affiliate Employees; Alumax Inc. Thrift Plan for Salaried Employees; Alumax Inc. Thrift Plan for Hourly Employees; Alumax Inc. Thrift Plan for Collectively Bargained Employees; and Reynolds Metals Company Savings Plan for Hourly Employees

2. Forms S-8 (Registration Nos. 33-22346, 33-49109, 33-60305, 333-27903, 333-62663, 333-79575, 333-36208, 333-37740, and 333-39708) Long Term Stock Incentive Plan; Alumax Inc. Long Term Incentive and Employee Equity Ownership Plans; Alcoa Stock Incentive Plan; Reynolds Metals Company 1999 Nonqualified Stock Option Plan; Reynolds Metals Company 1996 Nonqualified Stock Option Plan; Reynolds Metals Company 1992 Nonqualified Stock Option Plan; Reynolds Metals Company 1987 Nonqualified Stock Option Plan; Cordant Technologies Inc. 1989 Stock Awards Plan; Cordant Technologies Inc. 1996 Stock Awards Plan; Howmet International Inc. Amended and Restated 1997 Stock Awards Plan

3. Form S-3 (Registration No. 333-74874) Debt Securities, Preferred Stock, Common Stock, Warrants, Stock Purchase Contracts and Stock Purchase Units of Alcoa Inc., Trust Preferred Securities of Alcoa Trust I, and Guarantee of Trust Preferred Securities of Alcoa Trust I by Alcoa Inc.

4. Form S-3 (Registration No. 333-107926) Resale of Common Stock of Alcoa Inc. by Selling Shareholders

Commissioners:

We are aware that our report dated October 7, 2003, on our review of interim financial information of Alcoa Inc. and subsidiaries for the three and nine month periods ended September 30, 2003 and 2002 and included in the Company’s quarterly report on Form 10-Q for the quarter ended September 30, 2003, is incorporated by reference in its Registration Statements referred to above.

Very truly yours,

/s/ PricewaterhouseCoopers LLP

PricewaterhouseCoopers LLP

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