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MFS CALIFORNIA MUNICIPAL BOND FUND
Supplement to the Current Prospectus
As of February 10, 1999, the Expense Summary section of the Fund's
Prospectus is revised as follows:
1. EXPENSE SUMMARY
<TABLE>
<CAPTION>
<S> <C> <C> <C> <C>
Shareholder Transaction Expenses: Class A Class B Class C
Maximum Initial Sales Charge Imposed on Purchases of
Fund Shares (as a percentage of offering price)............................. 4.75% 0.00% 0.00%
Maximum Contingent Deferred Sales Charge (as a
percentage of original purchase price or
redemption proceeds, as applicable)......................................... See Below(1) 4.00% 1.00%
Annual Operating Expenses of the Fund (as a percentage of average daily net
assets):
Management Fees(2)............................................................. 0.20% 0.20% 0.20%
Rule 12b-1 Fees................................................................ 0.10%(3) 0.90%(4) 1.00%(4)
Other Expenses(5).............................................................. 0.24% 0.24% 0.24%
----- ----- -----
Total Operating Expenses....................................................... 0.54%(6) 1.34%(6) 1.44%
</TABLE>
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(1) Purchases of $1 million or more and certain purchases by retirement plans
are not subject to an initial sales charge; however, a contingent deferred
sales charge ("CDSC") of 1% will be imposed on such purchases in the event
of certain redemption transactions within 12 months following such
purchases (see "Information Concerning Shares of the Fund - Purchases" in
the Prospectus).
(2) The Adviser has voluntarily reduced its management fee for an indefinite
period of time to 0.20%. Absent this reduction, "Management Fees" would
have been 0.55%. See "Management of the Trust" below.
(3) The Fund has adopted a distribution plan for its shares in accordance with
Rule 12b-1 under the Investment Company Act of 1940, as amended (the "1940
Act") (the "Distribution Plan"), which provides that it will pay
distribution/service fees aggregating up to (but not necessarily all of)
0.35% per annum of the average daily net assets attributable to Class A
shares. The 0.10% per annum Class A distribution fee will commence on such
date as the Trustees of the Trust may determine. Payment of the Class A
service fee has been set by the Trust's Board of Trustees at 0.10% per
annum and may be increased to a maximum of 0.25% per annum on such date as
the Trustees of the Trust may determine. Distribution expenses paid under
this Plan, together with the initial sales charge, may cause long-term
shareholders to pay more than the maximum sales charge that would have
been permissible if imposed entirely as an initial sales charge. (See
"Information Concerning Shares of the Fund - Distribution Plan" below and
in the Prospectus).
(4) The Fund's Distribution Plan provides that it will pay
distribution/service fees aggregating up to 1.00% per annum of the average
daily net assets attributable to Class B and Class C shares, respectively.
Except in the case of the 0.25% per annum Class B service fee paid by the
Fund upon the sale of Class B shares in the first year, payment of the
Class B service fee has been set by the Trust's Board of Trustees at 0.10%
per annum and may be increased to a maximum of 0.25% per annum on such
date as the Trustees of the Trust may determine. Distribution expenses
paid under the Distribution Plan with respect to Class B or Class C
shares, together with any CDSC, may cause long-term shareholders to pay
more than the maximum sales charge that would have been permissible if
imposed entirely as an initial sales charge. (See "Information Concerning
Shares of the Fund - Distribution Plan" below and in the Prospectus.)
(5) The Fund has an expense offset arrangement which reduces the Fund's
custodian fee based upon the amount of cash maintained by the Fund with
its custodian and dividend disbursing agent, and may enter into other such
arrangements and directed brokerage arrangements (which would also have
the effect of reducing the Fund's expenses). These fee reductions, if any,
are not reflected under "Other Expenses."
(6) Absent the fee reductions mentioned above, "Total Expenses" would have
been 0.89%, 1.69% and 1.79% for Class A, Class B and Class C shares,
respectively.
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Example of Expenses
An investor would pay the following dollar amounts of expenses on a $1,000
investment in the Fund, assuming (a) a 5% annual return and (b) redemption at
the end of each of the time periods indicated (unless otherwise noted):
<TABLE>
<CAPTION>
<S> <C> <C> <C>
Period Class A Class B Class C
------ ------- ------- -------
(1) (1)
1 year.................... $ 53 $ 54 $ 14 $ 25 $ 15
3 years................... 64 72 42 46 46
5 years................... 76 93 73 79 79
10 years.................. 112 139(2) 139(2) 172 172
</TABLE>
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1. Assumes no redemption.
2. Class B shares convert to Class A shares approximately eight years after
purchase; therefore, years nine and ten reflect Class A expenses.
The purpose of the expense table above is to assist investors in
understanding the various costs and expenses that a shareholder of the Fund will
bear directly or indirectly. More complete descriptions of the following Fund
expenses are set forth in the following sections: (i) varying sales charges on
shares purchases - "Purchases"; (ii) varying CDSCs - "Purchases"; (iii)
management fees - "Investment Adviser"; and (iv) Rule 12b-1 (i.e., distribution
plan) fees - "Distribution Plan."
The "Example" set forth above should not be considered a representation of
past or future expenses of the Fund; actual expenses may be greater or less than
those shown.
***
2. MANAGEMENT OF THE TRUST- INVESTMENT ADVISER
Effective February 10, 1999, the Adviser has voluntarily reduced its
management fee for the Fund for an indefinite period of time to 0.20% per annum
of the Fund's average daily net assets. This fee reduction may be revised or
rescinded by the Adviser at any time without notice to shareholders.
***
3. INFORMATION CONCERNING SHARES OF THE TRUST - DISTRIBUTION PLAN
Current Level of Distribution and Service Fees. The Fund's Class A,
Class B and Class C distribution and service fees are 0.10%, 0.90% and 1.00%,
respectively.
The 0.10% per annum Class A distribution fee will commence on such date
as the Trustees of the Trust may determine. Payment of the Class A service fee
has been set by the Trust's Board of Trustees at 0.10% per annum and may be
increased to a maximum of 0.25% per annum on such date as the Trustees of the
Trust may determine. Except in the case of the 0.25% per annum Class B service
fee paid by the Fund upon the sale of Class B shares in the first year, payment
of the Class B service fee has been set by the Trust's Board of Trustees at
0.10% per annum and may be increased to a maximum of 0.25% per annum on such
date as the Trustees of the Trust may determine.
The date of this Supplement is February 10, 1999.
