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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 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 Partnership as of, and for, the periods presented
       in this quarterly 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)) 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 quarterly report
              is being prepared;

       b)     Evaluated the effectiveness of the Partnership's disclosure
              controls and procedures and presented in this quarterly 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

       c)     Disclosed in this report any change in the Partnership's
              internal control over financial reporting that occurred during
              the Partnership's most recent fiscal quarter that has
              materially affected, or is reasonably 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 12, 2006



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