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                                                                Exhibit 31.2

                    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 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 report.

3.     Based on my knowledge, the financial statements, and other financial
       information included in this 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 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 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 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 third 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 Audit
       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.
                           November 5, 2004