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                                                                    Exhibit 99.1

                         INCOME GROWTH PARTNERS, LTD. X
                        A California Limited Partnership
                    CERTIFICATION OF CHIEF EXECUTIVE OFFICER
                            Section 302 Certification

I, David W. Maurer, certify that:

1. I have reviewed this annual report on Form 10-KSB of INCOME GROWTH PARTNERS,
LTD. X, a California Limited Partnership (the "registrant");

2. Based on my knowledge, this annual report does not contain any untrue
statement of a material fact or omit to state a material fact necessary in order
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
annual report;

3. Based on my knowledge, the financial statements, and other financial
information included in this annual 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 annual 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 we have:

    a)   designed such disclosure controls and procedures 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 annual 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
         annual report (the "Evaluation Date"); and

    c)   presented in this annual report our conclusions about the effectiveness
         of the disclosure controls and procedures based 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 function):

    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
annual report whether or not 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: March 21, 2003                        By:    /s/ DAVID W. MAURER
                                                 ------------------------------
                                                         David W. Maurer
                                                     Chief Executive Officer
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                                                        Exhibit 99.1 (Continued)

                         INCOME GROWTH PARTNERS, LTD. X
                        A California Limited Partnership
                    CERTIFICATION OF CHIEF FINANCIAL OFFICER
                            Section 302 Certification

I, Timothy C. Maurer, certify that:

1. I have reviewed this annual report on Form 10-KSB of INCOME GROWTH PARTNERS,
LTD. X, a California Limited Partnership (the "registrant");

2. Based on my knowledge, this annual report does not contain any untrue
statement of a material fact or omit to state a material fact necessary in order
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
annual report;

3. Based on my knowledge, the financial statements, and other financial
information included in this annual 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 annual 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 we have:

    d)   designed such disclosure controls and procedures 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 annual report is
         being prepared;

    e)   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
         annual report (the "Evaluation Date"); and

    f)   presented in this annual report our conclusions about the effectiveness
         of the disclosure controls and procedures based 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 function):

    c)   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

    d)   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
annual report whether or not 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: March 21, 2003                        By:    /s/ TIMOTHY C. MAURER
                                                 ------------------------------
                                                        Timothy C. Maurer
                                                     Chief Financial Officer