Exhibit 99.1

TIDEWATER INC. Ÿ Pan-American Life Center Ÿ 601 Poydras Street, Suite 1900 Ÿ New Orleans, LA 70130 Ÿ Telephone (504) 568-1010 Ÿ Fax (504) 566-4582

Tidewater Announces Conference Call

NEW ORLEANS, May 6, 2013–Tidewater Inc. (NYSE: TDW) announced today that its fiscal 2013 fourth quarter (ended March 31, 2013) earnings release and conference call have been scheduled for Tuesday, May 21, 2013. The press release will be issued before the market opens, and the conference call will begin at 10:00 a.m. Central time.

Investors and interested parties may listen to the teleconference via telephone by calling 1-888-771-4371 if calling from the U.S. or Canada (1-847-585-4405 if calling from outside the U.S.) and ask for the “Tidewater” call just prior to the scheduled start. A replay of the conference call will be available beginning at 12:00 p.m. Central time on May 21, 2013, and will continue until 11:59 p.m. Central time on May 23, 2013. To hear the replay, call 1-888-843-7419 (1-630-652-3042 if calling from outside the U.S.). The conference call ID number is 34792519.

A simultaneous webcast of the conference call will be available online at the Tidewater Inc. website, (http://www.tdw.com). The online replay will be available until June 8, 2013.

Tidewater is the leading provider of larger Offshore Service Vessels (OSVs) to the global energy industry.

CONTACT: Tidewater Inc., New Orleans

Joe Bennett, Executive Vice President and Chief Investor Relations Officer

504-566-4506

SOURCE: Tidewater Inc.

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