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                                                                           EX-99

FOR IMMEDIATE RELEASE:

      MEDIA CONTACTS:               INVESTOR CONTACTS:
      BancWest Corporation:         BancWest Corporation:
      Gerry Keir (808) 525-7086     Howard Karr (808) 525-8800
      Bank of the West              Bank of the West:
      Bob Raye (925) 942-8585       Douglas Grigsby (925) 942-8395
      SierraWest Bancorp:           SierraWest Bancorp:
      Sheryl Seapy (415) 296-7383   David Broadley (530) 582-3000

       BANCWEST CORPORATION TO ACQUIRE SIERRAWEST BANCORP. 

       Bank of the West Strengthens Northern California Franchise, Expands to 
       Nevada

      (San Francisco, California -- February 25, 1999) --BancWest Corporation
(NYSE: BWE), parent of Bank of the West, announced today that it has signed a
definitive agreement to acquire SierraWest Bancorp (Nasdaq: SWBS), parent
company of SierraWest Bank, in a $194 million stock transaction.

      SierraWest will be merged into Bank of the West. The combination will
enhance Bank of the West's presence in Northern California and expand the bank's
branch network into Nevada. SierraWest, with total assets of $879 million, has
20 branches extending along the Interstate 80 corridor between the East Bay and
Reno. SierraWest is one of the top originators of U.S. Small Business
Administration (SBA) loans in the nation with ten lending offices focused on SBA
lending activities in California, Nevada, Oregon, Washington, Colorado and
Tennessee.

      According to BancWest Chairman and Chief Executive Officer Walter A. Dods,
Jr., the merger provides a niche market opportunity for the company. "SierraWest
has an impressive record of commercial lending, especially to small businesses,
and will provide us with a competitive edge in servicing the financial needs of
the small business market," Dods said.

      Don J. McGrath, president of BancWest Corp. and president and chief
executive officer of Bank of the West, added that "the SBA business line segment
of SierraWest complements Bank of the West's lending in other specialized
markets, including religious lending, consumer 
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finance, equipment leasing, real estate and business banking."

      San Francisco-based Bank of the West, which has 143 branches in Northern
California, Oregon, Washington and Idaho, is the Mainland subsidiary of BancWest
Corporation ($15.0 billion assets). The acquisition of SierraWest will increase
Bank of the West's assets to $8.6 billion; it is the fifth largest bank in
California.

      SierraWest Bancorp shareholders will receive 0.82 shares of BancWest
common stock for each share of SierraWest common stock. Based on BancWest's
closing price of $43.00 on February 25, 1999, the value for SierraWest would be
$35.26 per share.

      The transaction will be accounted for as a pooling of interests. Based on
issuance of about 4.6 million BancWest shares, the transaction is expected to be
neutral to BancWest's per-share earnings in 1999, exclusive of restructuring
charges. The transaction is expected to be 2.0% accretive to BancWest's
per-share earnings in 2000, when synergies from the merger will have been fully
achieved.

      The merger agreement provides BancWest with an option to purchase 19.99%
of SierraWest's shares under specified circumstances.

      The boards of BancWest, Bank of the West and SierraWest have all approved
the agreement. The merger requires approval from SierraWest's shareholders and
federal and state banking regulators. Once all approvals have been received, the
merger is expected to close in mid-1999.

      "Joining forces with Bank of the West gives SierraWest's customers access
to a regional bank which has the same kind of community banking roots that we
do. Bank of the West will bring SierraWest's customers a much broader line of
products including investments, mutual funds and annuities, insurance, leasing,
trust and private banking services," said William T. Fike, president and chief
executive officer of SierraWest.

      Fike will join the consolidated company with responsibility for all SBA
lending by Bank of the West and First Hawaiian Bank.

      "The transaction gives SierraWest's shareholders excellent value,
increased dividends 
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and a significant equity position in a much larger, more diversified regional
financial services company with excellent growth prospects. And Bank of the West
has always supported the communities where it does business," Fike said.

      BancWest Corporation is a bank holding company with total assets of $15.0
billion headquartered in Honolulu, Hawaii, with an administrative headquarters
in San Francisco, California. BancWest's principal subsidiaries are Bank of the
West and Honolulu-based First Hawaiian Bank, with 59 branches in Hawaii, Guam
and Saipan.

      San Francisco-based Bank of the West was founded in 1874 and is the third
oldest bank in California. It operates 143 branches -- 103 in Northern and
Central California, 29 in Oregon, eight in Washington state and three in Idaho.

      SierraWest Bancorp is the holding company for SierraWest Bank,
headquartered in Truckee, Calif., with branches in Sacramento, the Central
Valley, the Sierra foothills and Lake Tahoe regions of California and northern
Nevada. SierraWest expanded in April 1998 by acquiring Vacaville-based
Continental Pacific Bank.

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      (This release contains forward-looking statements, including statements
regarding performance of the company after the merger. Such statements are
subject to risks and uncertainties that may cause actual results to differ
materially from those presented. Factors that could cause such differences
include: failure to fully realize expected cost savings from the merger; lower
than expected revenues following the merger; problems or delays in bringing
together the two companies; legal and regulatory risks and uncertainties;
global, national and local economic conditions; competition and change in the
financial services business; and other factors described in our recent filings
with the Securities and Exchange Commission.)