<PAGE>

                          SHELBOURNE PROPERTIES I, INC.
                          FORM 10Q - SEPTEMBER 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:    November 12, 2003                           /s/ Michael L. Ashner
                                                     ---------------------------
                                                     Michael L. Ashner
                                                     Chief Executive Officer


<PAGE>

                          SHELBOURNE PROPERTIES I, INC.
                          FORM 10Q - SEPTEMBER 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:  November 12, 2003                               /s/ Carolyn B. Tiffany
                                                       ------------------------
                                                       Carolyn B. Tiffany
                                                       Chief Financial Officer