EXHIBIT 99
                                                                      ----------


                                     [LOGO]


April 27, 2004

Dear Shareholder:

Enterprise  Bancorp,  Inc.'s net income  amounted to $1.7  million for the three
months  ended March 31,  2004,  compared to $0.5  million for the same period in
2003.  The primary  factors  contributing  to the  increase in net income in the
first quarter of 2004, as compared to the first quarter of 2003, were a decrease
in the  provision  for income tax  expenses  (primarily  due to the $1.9 million
provision in 2003 related to changes in the  Massachusetts  tax laws  concerning
the company's REIT  subsidiary(1)  ), offset by a decrease in net gains on sales
of  investment  securities,  and an  increase in the  provision  for loan losses
during the first quarter of 2004.

At March 31, 2004,  total assets amounted to $776.1  million,  an increase of 6%
from March 31,  2003.  Total loans were  $505.7  million at March 31,  2004,  an
increase of 17% over the prior year. Deposits plus repurchase agreements grew to
$703.0  million at March 31,  2004,  an increase of 8% over March 31,  2003.  In
addition,  the Investment  Management and Trust Group reported investment assets
under  management of $386.7  million,  a 15% increase versus one year ago. Total
assets,  investment  assets under  management,  and mortgage  loans serviced for
others  amounted to $1.2 billion at March 31, 2004, an increase of 8% from March
31, 2003.

At our February 11 annual Employees' Celebration of Success, the Bank recognized
the retirement of three valued members of the Enterprise  Bank family.  VP/Human
Resources  Manager Jeannette  Sheehan,  Mary Lou Allen from the Mortgage Center,
and SVP/Sr.  Trust Officer Paul Shaughnessy  from our Investment  Management and
Trust Group are ending  successful  banking  careers.  These  three  individuals
represent over 70 combined years of service to the banking  community in Greater
Lowell.  We salute  Jeannie,  Mary Lou and Paul for their  contributions  to the
success of  Enterprise  Bank during  their  tenure  here,  and we wish them good
health and happiness in the years ahead.  For those  shareholders  and customers
that did business with Paul Shaughnessy, he will be available on a limited basis
throughout 2004 to assist clients during the transition period.

The first quarter of 2004 was a period of  significant  business  development at
Enterprise.  On March 15, we opened our twelfth  branch office at 63 Park Street
in Andover. Staffed by a talented group of local professionals, our Andover team
was very  encouraged  by the warm  welcome we  received  from the large group of
business and community leaders on hand at ribbon-cutting ceremonies.  After only
thirty days,  business is strong in Andover.  Our new branch reports deposits of
approximately of $20 million!  Such growth is truly impressive,  and far exceeds
our original projections. The 63 Park Street facility is about one half the size
of our  typical  branch  facility.  We opened  there to create a presence in the
Andover  market  quickly,  as  we  wanted  to  take  full  advantage  of  market
opportunities  presented  by the current  bank-acquisition  turmoil.  Due to the
strong growth we've  experienced,  and the  tremendous  potential for Enterprise
Bank in the Andover  area,  we plan to relocate  into a larger,  more  permanent
office in downtown  Andover at 8 High Street,  within the next 12-18 months.  We
plan to share more  details with you  concerning  this major  initiative  in the
months ahead.

At our April 20 meeting of the Board of Directors,  it was voted to increase the
annual  dividend to 43 cents per share,  payable on June 25 to  shareholders  of
record as of June 4, 2004. The 2004 dividend represents a 13% increase over last
year's payout of 38 cents per share.  The majority of shareholders  have elected
to  participate  in our  dividend  reinvestment  plan.  We are pleased to invite
additional   shareholders   interested  in  dividend   reinvestment  to  contact
Equiserve,   Inc.,  our  recently-appointed   transfer  agent,   toll-free,   at
1-888-218-4390  prior  to  June  4  to  arrange  for  dividend  reinvestment.  A
confirmation of your dividend reinvestment transaction,  including the number of
additional shares purchased, will be sent to all participants on June 25.

We appreciate the positive reaction we've received from shareholders  concerning
our 2003  annual  report.  As a  reminder,  in  preparation  for our 2004 annual
meeting,  proxy materials were mailed to all  shareholders on March 26. The 2004
annual  meeting is scheduled for May 4, 2004, at 4 p.m. at the American  Textile
History  Museum,  491  Dutton  Street  in  Lowell.  It  is  important  that  you
participate by voting your proxy as soon as possible, whether or not you plan to
join us on May 4. A ballot and  self-addressed  envelope to Equiserve  Inc., was
enclosed  in the March  mailing.  We look  forward to the  annual  meeting as it
presents an opportunity for us to discuss plans for the bank's  continued growth
and profitability.  Our annual meeting also gives us a special chance to express
our appreciation to you for your loyal support over the past sixteen years.

Sincerely,



/s/ George L. Duncan    /s/ Richard W. Main             /s/ John P. Clancy, Jr.
- --------------------    -------------------------       -----------------------
George L. Duncan        Richard W. Main                 John P. Clancy, Jr.
Chairman/Chief          President/Chief Lending         President/Enterprise
Executive Officer       Officer/Chief Operating         Bancorp Inc./EVP/
                        Officer                         Treasurer/Enterprise
                                                        Bank



(1) In June 2003,  the company  subsequently  reversed $0.8 million of the March
tax  charge.  The  reversal  was  due  to a  settlement  agreement  between  the
Massachusetts   Department   of  Revenue  and   Enterprise   Bank,   along  with
approximately   sixty-five  other   Massachusetts   banks,   regarding  disputed
retroactive   assessments  for  1999  through  2002.  Under  the  terms  of  the
settlement,  the tax expense recorded in 2003 related to prior year assessments,
was approximately $1.1 million.






                    Enterprise Bancorp, Inc. and Subsidiaries

                              STATEMENTS OF INCOME
                                   (unaudited)



                                                               Three Months Ended March 31,
                                                            ---------------------------------
                                                                  2004             2003
                                                            ---------------  ----------------
                                                                        
INTEREST AND DIVIDEND INCOME
    Loans                                                      $ 7,559,331    $ 6,889,722
    Investment securities                                        1,723,787      2,501,598
    Short term investments                                          14,358         24,018
                                                               -----------    -----------
               Total interest and dividend income                9,297,476      9,415,338
                                                               -----------    -----------

INTEREST EXPENSE
    Deposits                                                     1,455,989      1,852,407
    Repurchase agreements                                           10,541          2,926
    Federal Home Loan Bank borrowings                               56,653         22,599

    Junior subordinated debentures                                 294,305        294,305
                                                               -----------    -----------
               Total interest expense                            1,817,488      2,172,237
                                                               -----------    -----------

NET INTEREST INCOME                                              7,479,988      7,243,101

    Provision for loan losses                                      750,000        300,000
                                                               -----------    -----------
      Net interest income after provision for loan losses        6,729,988      6,943,101
                                                               -----------    -----------


       Non-interest income                                       1,549,176      1,588,699
       Net gains on sales of investment securities                 630,917      1,315,754
       Operating expenses                                       (6,199,090)    (5,882,608)
                                                               -----------    -----------
                    Income before provision for income taxes     2,710,991      3,964,946

       Provision for income taxes                                  995,745      3,460,872
                                                               -----------    -----------
NET INCOME                                                     $ 1,715,246    $   504,074
                                                               ===========    ===========

EARNINGS PER SHARE
Basic earnings per common share                                $      0.48    $      0.14
                                                               ===========    ===========

Diluted earnings per common share                              $      0.45    $      0.14
                                                               ===========    ===========

Dividend per common share (1)                                  $        -     $         -
                                                               ===========    ===========

Basic weighted average common shares outstanding (2)             3,605,344      3,533,488
                                                               ===========    ===========

Diluted weighted average common shares outstanding               3,789,679      3,660,855
                                                               ===========    ===========



(1)  Annual  dividends  are  generally  declared  in the second  quarter of each
     fiscal year.

(2)  Weighted  average  common  shares  outstanding  have  increased  due to the
     exercise of employee stock options and  reinvestment  of dividends from the
     dividend reinvestment plan.





                    Enterprise Bancorp, Inc. and Subsidiaries

                                 BALANCE SHEETS
                                   (unaudited)




                                                       March 31, 2004     December 31, 2003   March 31, 2003
                                                    -------------------   ------------------ ----------------
                                                                                   
ASSETS
   Cash and due from banks                            $    32,146,863    $    31,101,961    $    34,252,334
   Short term investments                                  38,500,000         14,000,000         38,500,000
   Investment securities                                  179,320,102        196,308,098        208,002,227
   Loans                                                  505,731,228        488,839,152        431,593,565
       Allowance for loan losses                          (10,329,239)        (9,986,425)        (9,744,360)
                                                      ---------------    ---------------    ---------------
       Net loans                                          495,401,989        478,852,727        421,849,205
                                                      ---------------    ---------------    ---------------
   Bank premises and equipment                             12,217,891         12,429,021         13,271,471
   Intangible assets                                        6,496,931          6,530,123          6,629,700
   Other assets                                            12,041,146         12,323,241         10,490,826
                                                      ---------------    ---------------    ---------------

TOTAL ASSETS                                          $   776,124,922    $   751,545,171    $   732,995,763
                                                      ===============    ===============    ===============

LIABILITIES AND STOCKHOLDERS' EQUITY
   Deposits                                           $   688,499,974    $   660,824,382    $   651,471,411
   Repurchase agreements                                   14,505,876            953,924            962,832
   Federal Home Loan Bank borrowings                        1,932,500         20,470,000         10,470,000
   Junior subordinated debentures                          10,825,000         10,825,000         10,825,000
   Other liabilities                                        3,143,034          3,721,291         10,498,451
                                                      ---------------    ---------------    ---------------
        Total liabilities                                 718,906,384        696,794,597        684,227,694
                                                      ---------------    ---------------    ---------------

   Stockholders' equity                                    54,282,128         52,511,133         46,134,145
   Net unrealized appreciation on investment
           securities, net of taxes                         2,936,410          2,239,441          2,633,924
                                                      ---------------    ---------------    ---------------
        Total stockholders' equity                         57,218,538         54,750,574         48,768,069
                                                      ---------------    ---------------    ---------------

TOTAL LIABILITIES & STOCKHOLDERS' EQUITY              $   776,124,922    $   751,545,171    $   732,995,763
                                                      ===============    ===============    ===============


   Investment assets under management                 $   386,661,205    $   375,296,992    $   336,537,613
                                                      ===============    ===============    ===============

   Mortgage loans serviced for others                 $    14,741,485    $    15,077,295    $    16,975,274
                                                      ===============    ===============    ===============

   Total assets, investment assets under management
     and mortgage loans serviced for others           $ 1,177,527,612    $ 1,141,919,458    $ 1,086,508,650
                                                      ===============    ===============    ===============