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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 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 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.
                                      August 9, 2004