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Exhibit 31.1

                    Certification of Chief Executive Officer
            Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002

I, Richard B. Collins, President and Chief Executive Officer, certify that:

1. I have reviewed this Quarterly Report on Form 10-Q of United Financial
Bancorp, Inc.;

2. Based on my knowledge, this quarterly report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this quarterly
report;

3. Based on my knowledge, the financial statements, and other financial
information included in this quarterly report, fairly present in all material
respects the financial condition, results of operations and cash flows of the
registrant as of, and for, the periods presented in this quarterly report;

4. The registrant's other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:

      (a) Designed such disclosure controls and procedures, or caused such
      disclosure controls and procedures to be designed under our supervision,
      to ensure that material information relating to the registrant, including
      its consolidated subsidiaries, is made known to us by others within those
      entities, particularly during the period in which this quarterly report is
      being prepared;

      (b) Evaluated the effectiveness of the registrant's disclosure controls
      and procedures and presented in this quarterly report our conclusions
      about the effectiveness of the disclosure controls and procedures, as of
      the end of the period covered by this quarterly report based on such
      evaluation; and

      (c) Disclosed in this quarterly report any change in the registrant's
      internal control over financial reporting that occurred during the
      registrant's most recent fiscal quarter that has materially affected, or
      is reasonably likely to materially affect, the registrant's internal
      control over financial reporting; and

5. The registrant's other certifying officer and I have disclosed, based on our
most recent evaluation of internal control over financial reporting, to the
registrant's auditors and the audit committee of the registrant's board of
directors (or persons performing the equivalent functions):

      (a) All significant deficiencies and material weaknesses in the design or
      operation of internal control over financial reporting which are
      reasonably likely to adversely affect the registrant's ability to record,
      process, summarize and report financial information; and

      (b) Any fraud, whether or not material, that involves management or other
      employees who have a significant role in the registrant's internal control
      over financial reporting.


Date: November 14, 2005                    /s/ Richard B. Collins
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                                           Richard B. Collins
                                           President and Chief Executive Officer


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