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Exhibit 10
INDEPENDENT AUDITORS' CONSENT
We consent to the incorporation by reference in this Post-Effective Amendment
No. 40 to Registration Statement No. 2-50409 of MFS Series Trust IX, of our
report dated June 7, 2000 appearing in the annual report to shareholders for the
year ended April 30, 2000 for MFS Bond Fund, MFS Limited Maturity Fund, MFS
Municipal Limited Maturity Fund, MFS Intermediate Investment Grade Bond Fund and
MFS Research Bond Fund, each a series of MFS Series Trust IX, and to the
references to us under the headings "Financial Highlights" in the Prospectuses
and "Independent Auditors and Financial Statements" in the Statements of
Additional Information, both of which are part of such Registration Statement.
DELOITTE & TOUCHE, LLP
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Deloitte & Touche, LLP
Boston, Massachusetts
August 25, 2000
