EXHIBIT 99.(a)(5)(iii)

May 12, 2004

FOR IMMEDIATE RELEASE                                  CONTACT: Mel Switzer, Jr.
                                                       (707) 935-3200


       SONOMA VALLEY BANCORP EXTENDS TENDER OFFER TO FRIDAY, MAY 21, 2004

     Sonoma,  CA - May  12,  2004  -  Sonoma  Valley  Bancorp  (OTC  BB -  SBNK)
("Sonoma"),  announced the extension of its tender offer from 2:00 p.m. (EST) on
May 14, 2004 to the new  expiration  date of 2:00 p.m. (EST) on May 21, 2004. As
previously  announced  on April 6,  2004,  Sonoma  commenced  a tender  offer to
purchase  up to 100,000  shares of its  outstanding  common  stock at $35.00 per
share.  Tendering  shareholders  whose shares are  purchased in the tender offer
will be paid for the purchased shares after the expiration of the offer period.

     Sonoma is  extending  its tender  offer  because  there was a  distribution
problem  that  delayed  the  mailing  of the  tender  offer  documents  to  some
shareholders.  The problem was corrected; however, Sonoma is extending the offer
to  allow  all  shareholders  ample  time  to  consider  whether  they  wish  to
participate in the offer and to tender their shares.

     Information  regarding  Sonoma's tender offer was filed with the Securities
and Exchange  Commission on Schedule TO and can be viewed at the  Securities and
Exchange   Commission's  website  at  www.sec.gov  or  on  Sonoma's  website  at
www.sonomavalleybank.com.

     Shareholders  who have  questions,  need assistance or would like copies of
the tender offer documents may contact Mel Switzer,  Jr., Sonoma Valley Bancorp,
202 W. Napa Street, Sonoma, California 95476, Telephone: (707) 935-3200.

     Shareholders should review the offer to purchase as supplemented, letter of
transmittal and related  documents mailed to shareholders and made available for
distribution  to  beneficial  owners of Sonoma  Valley  Bancorp's  common stock.
Shareholders  are urged to carefully  read these  materials  prior to making any
decision with respect to the offer.

     Neither Sonoma, nor its Board of Directors, is making any recommendation to
shareholders as to whether to tender or refrain from tendering their shares into
the tender offer.  Shareholders must decide how many shares they will tender, if
any, for purchase by Sonoma.


This news release includes forward-looking statements,  which are not historical
facts are and which are  subject to risks and  uncertainties  that  could  cause
actual results to differ materially from those expressed in the  forward-looking
statements.  Management  believes there are benefits to  shareholders  in making
these statements.  This forward-looking  statement includes,  but is not limited
to, Sonoma's ability to enhance  shareholder value.  Future events are difficult
to predict, and the expectations described above are necessarily subject to risk
and  uncertainty  that  may  cause  actual  results  to  differ  materially  and
adversely. In addition,  discussions about risks and uncertainties are set forth
from  time  to time in  Sonoma's  publicly  available  Securities  and  Exchange
Commission  filings.  Sonoma Valley  Bancorp  (NASDAQ-OTCBB:SBNK)  undertakes no
obligation  to  publicly  revise  these  forward-looking  statements  to reflect
subsequent events or circumstances.