<PAGE>

                          SHELBOURNE PROPERTIES I, INC.
                            FORM 10Q - JUNE 30, 2003


EXHIBIT 31

                                 CERTIFICATIONS

I, Michael L. Ashner, certify that:

1.     I have reviewed this quarterly report on Form 10-Q of Shelbourne
       Properties I, 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 officers and I are responsible for
       establishing and maintaining disclosure controls and procedures (as
       defined in Exchange Act Rules 13a-14 and 15d-14) 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 is made known to us, particularly during the period in
          which this quarterly report is being prepared:

       b) evaluated the effectiveness of the registrant's disclosure controls
          and procedures as of a date within 90 days prior to the filing date of
          this quarterly report (the "Evaluation Date"); and

       c) presented in this quarterly report our conclusions about the
          effectiveness of the disclosure controls and procedures on our
          evaluation as of the Evaluation Date;

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

       a) all significant deficiencies in the design or operation of internal
          controls which could adversely affect the registrant's ability to
          record, process, summarize and report financial data and have
          identified for the registrant's auditors any material weaknesses in
          internal controls; and

       b) any fraud, whether or not material, that involves management or other
          employees who have a significant role in the registrant's internal
          controls; and

6.     The registrant's other certifying officers and I have indicated in this
       quarterly report whether there were significant changes in internal
       controls or in other factors that could significantly affect internal
       controls subsequent to the date of our most recent evaluation, including
       any corrective actions with regard to significant deficiencies and
       material weaknesses.


Date:  August 11, 2003                             /s/ Michael L. Ashner
                                                   -----------------------------
                                                   Michael L. Ashner
                                                   Chief Executive Officer




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<PAGE>

                          SHELBOURNE PROPERTIES I, INC.
                            FORM 10Q - JUNE 30, 2003


                                 CERTIFICATIONS

I, Carolyn B. Tiffany, certify that:

1.     I have reviewed this quarterly report on Form 10-Q of Shelbourne
       Properties, I 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 officers and I are responsible for
       establishing and maintaining disclosure controls and procedures (as
       defined in Exchange Act Rules 13a-14 and 15d-14) 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 is made known to us, particularly during the period in
          which this quarterly report is being prepared:

       b) evaluated the effectiveness of the registrant's disclosure controls
          and procedures as of a date within 90 days prior to the filing date of
          this quarterly report (the "Evaluation Date"); and

       c) presented in this quarterly report our conclusions about the
          effectiveness of the disclosure controls and procedures on our
          evaluation as of the Evaluation Date;

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

       a) all significant deficiencies in the design or operation of internal
          controls which could adversely affect the registrant's ability to
          record, process, summarize and report financial data and have
          identified for the registrant's auditors any material weaknesses in
          internal controls; and

       b) any fraud, whether or not material, that involves management or other
          employees who have a significant role in the registrant's internal
          controls; and

6.     The registrant's other certifying officers and I have indicated in this
       quarterly report whether there were significant changes in internal
       controls or in other factors that could significantly affect internal
       controls subsequent to the date of our most recent evaluation, including
       any corrective actions with regard to significant deficiencies and
       material weaknesses.


Date:  August 11, 2003                       /s/ Carolyn B. Tiffany
                                             -----------------------------
                                             Carolyn B. Tiffany
                                             Chief Financial Officer




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