Alcoa (AA) 10-Q 2019 Q1 Quarterly report

EXHIBIT 18.1

May 9, 2019

Board of Directors

Alcoa Corporation

201 Isabella Street

Pittsburgh PA, 15212

Dear Directors:

We are providing this letter to you for inclusion as an exhibit to Alcoa Corporation’s(the “Company”)Quarterly Report onForm 10-Q for the period ended March 31, 2019 (the “Form 10-Q”) pursuant to Item 601 of Regulation S-K.

We have been provided a copy of the Company’sForm 10-Q.  Footnote H.therein describes the changes in accounting principles from the last-in, first-out (LIFO) method of inventory costing to the average cost method of inventory valuation. It should be understood that the preferability of one acceptable method of accounting over another for determining the cost of inventoryhas not been addressed in any authoritative accounting literature, and in expressing our concurrence below we have relied on management’s determination that this change in accounting principle is preferable. Based on our reading of management’s stated reasons and justification for this change in accounting principle in the Form 10-Q, and our discussions with management as to their judgment about the relevant business planning factors relating to the change, we concur with management that such change represents, in the Company’s circumstances, a change to a preferable accounting principle in conformity with Accounting Standards Codification 250, Accounting Changes and Error Corrections.

We have not audited any financial statements of the Company as of any date or for any period subsequent to December 31, 2018.  Accordingly, our comments are subject to change upon completion of an audit of the financial statements covering the period of the accounting change.

Very truly yours,

PricewaterhouseCoopers LLP

Pittsburgh, Pennsylvania