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                                                                    Exhibit 31


                   CHIEF EXECUTIVE OFFICER CERTIFICATION

I, Douglas E. Hill, certify that:

1.  I have reviewed this quarterly report on Form 10-Q of The Jones
    Financial Companies, L.L.L.P.

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 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 Partnership as of, and for, the periods presented
    in this annual report.

4.  The Partnership'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)) and internal
    control over financial reporting (as defined in Exchange Act Rules
    13a-15(f) and 15d-15(f)) for the Partnership 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
       Partnership, 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) Designed such internal control over financial reporting, or caused
       such internal control over financial reporting to be designed under
       our supervision, to provide reasonable assurance regarding the
       reliability of financial reporting and the preparation of financial
       statements for external purposes in accordance with generally
       accepted accounting principles;

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

    d) Disclosed in this report any change in the Partnership's internal
       control over financial reporting that occurred during the
       Partnership's fourth quarter that has materially affected, or is
       reasonable likely to materially affect, the Partnership's internal
       control over financial reporting; and

5.  The Partnership's other certifying officer and I have disclosed,
    based on our most recent evaluation of internal control over
    financial reporting, to the Partnership's auditors and the Executive
    Committee:

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

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

                           /s/ Douglas E. Hill
                           ---------------------------------------
                           Chief Executive Officer

                           The Jones Financial Companies, L.L.L.P.
                           May 4, 2004

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                                                                   Exhibit 31


                    CHIEF FINANCIAL OFFICER CERTIFICATION

I, Steven Novik, certify that:

1.  I have reviewed this quarterly report on Form 10-Q of The Jones
    Financial Companies, L.L.L.P.

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 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 Partnership as of, and for, the periods presented
    in this annual report.

4.  The Partnership'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)) and internal
    control over financial reporting (as defined in Exchange Act Rules
    13a-15(f) and 15d-15(f)) for the Partnership 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
       Partnership, 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) Designed such internal control over financial reporting, or caused
       such internal control over financial reporting to be designed under
       our supervision, to provide reasonable assurance regarding the
       reliability of financial reporting and the preparation of financial
       statements for external purposes in accordance with generally
       accepted accounting principles;

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

    d) Disclosed in this report any change in the Partnership's internal
       control over financial reporting that occurred during the
       Partnership's fourth quarter that has materially affected, or is
       reasonable likely to materially affect, the Partnership's internal
       control over financial reporting; and

5.  The Partnership's other certifying officer and I have disclosed,
    based on our most recent evaluation of internal control over
    financial reporting, to the Partnership's auditors and the Executive
    Committee:

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

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

                                    /s/ Steven Novik
                                    ---------------------------------------
                                    Chief Financial Officer
                                    The Jones Financial Companies, L.L.L.P.
                                    May 4, 2004