mca.htm

Before you invest, you may want to review the fund’s prospectus, which contains more information about the fund and its risks. You can find the fund’s prospectus and other information about the fund, including the fund’s statement of additional information, online at funds.mfs.com. You can also get this information at no cost by calling 1-800-225-2606 or by sending an e-mail request to orderliterature@mfs.com. The fund’s prospectus and statement of additional information, both dated July 29, 2011, as may be supplemented from time to time, are incorporated by reference into this Summary Prospectus.

The fund’s investment objective is to seek total return with an emphasis on income exempt from federal income tax and personal income tax, if any, of California, but also considering capital appreciation.

You may qualify for sales charge reductions if you and certain members of your family invest, or agree to invest in the future, at least $50,000 in MFS Funds. More information about these and other waivers and reductions is available from your financial intermediary and in “Sales Charges and Waivers or Reductions” on page 8 of the fund’s prospectus and “Waivers of Sales Charges” on page 27 of the fund’s statement of additional information Part I.

Share Class	A	B	C
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	4.75%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)	1.00% #	4.00%	1.00%

Share Class	A	B	C
Management Fee	0.45%	0.45%	0.45%
Distribution and/or Service (12b-1) Fees	0.25%	1.00%	1.00%
Other Expenses	0.15%	0.15%	0.15%
Total Annual Fund Operating Expenses	0.85%	1.60%	1.60%
Fee Reductions and/or Expense Reimbursements 1	(0.15)%	(0.13)%	0.00%
Total Annual Fund Operating Expenses After Fee Reductions and/or Expense Reimbursements	0.70%	1.47%	1.60%

#	On shares purchased without an initial sales charge and redeemed within 18 months of purchase for shares purchased on or after August 1, 2012, and within 24 months of purchase for shares purchased prior to August 1, 2012.

The fund’s distributor, MFD, has agreed in writing to waive the Class A service fee to 0.10% of the fund’s average daily net assets annually until modified by a vote of the fund’s Board of Trustees, but such agreement will continue until at least July 31, 2012. In addition, for one year from the date of sale of Class B shares, assets attributable to such Class B shares are subject to the 0.25% Class B service fee of the fund’s average daily net assets annually. On assets attributable to all other Class B shares, the fund’s distributor, MFD, has agreed in writing to waive the Class B service fee to 0.10% of the fund’s average daily net assets annually until modified by a vote of the fund’s Board of Trustees, but such agreement will continue until at least July 31, 2012.

The example assumes that: you invest $10,000 in the fund for the time periods indicated and you redeem your shares at the end of the time periods (unless otherwise indicated); your investment has a 5% return each year; and the fund’s operating expenses remain the same.

	1 YEAR	3 YEARS	5 YEARS	10 YEARS
Class A Shares	$543	$719	$910	$1,461
Class B Shares assuming
redemption at end of period	$550	$792	$1,059	$1,688
no redemption at end of period	$150	$492	$859	$1,688
Class C Shares assuming
redemption at end of period	$263	$505	$871	$1,900
no redemption at end of period	$163	$505	$871	$1,900

The fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These transaction costs, which are not reflected in “Annual Fund Operating Expenses” or in the “Example,” affect the fund’s performance. During the most recent fiscal year, the fund’s portfolio turnover rate was 24% of the average value of its portfolio.

The fund invests, under normal market conditions, at least 80% of its net assets in securities and other investments, the interest on which is exempt from federal income tax and personal income tax, if any, of California. Interest from the fund’s investments may be subject to the federal alternative minimum tax.

MFS may invest 25% or more of the fund’s assets in municipal instruments that finance similar projects, such as those relating to education, healthcare, housing, utilities, water or sewers. Municipal instruments whose interest is exempt from federal and state personal income tax include instruments issued by U.S. territories and possessions (such as Puerto Rico, Guam, and the U.S. Virgin Islands) and their political subdivisions and public corporations. Although MFS seeks to invest the fund’s assets in municipal instruments whose interest is exempt from federal and state personal income tax, MFS may also invest in taxable instruments.

While MFS may use derivatives for any investment purpose, to the extent MFS uses derivatives, MFS expects to use derivatives primarily to increase or decrease exposure to a particular market, segment of the market, or security, to increase or decrease interest rate exposure, or as alternatives to direct investments. Derivatives include futures, forward contracts, options, structured securities, inverse floating rate instruments, and swaps.

MFS uses a bottom-up investment approach to buying and selling investments for the fund. Investments are selected primarily based on fundamental analysis of individual instruments and their issuers in light of issuers’ current financial condition and current market, economic, political, and regulatory conditions. Factors considered may include the instrument’s credit quality, collateral characteristics, and indenture provisions, and the issuer’s management ability, capital structure, leverage, and ability to meet its current obligations. Quantitative models that systematically evaluate the structure of the debt instrument and its features may also be considered.

As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund. An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

Interest Rate Risk: The price of a debt instrument falls when interest rates rise and rises when interest rates fall. Instruments with longer maturities, or that do not pay current interest, are more sensitive to interest rate changes.

Credit Risk: The price of a debt instrument depends, in part, on the credit quality of the issuer, borrower, counterparty, or underlying collateral and can decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral, or changes in specific or general market, economic, industry, political, regulatory, geopolitical, or other conditions.

Municipal instruments not supported as to the payment of principal and interest by a state or local government may be subject to greater credit risk than municipal instruments that are supported by a state or local government.

Lower quality debt instruments (commonly referred to as “high yield securities” or “junk bonds”) can involve a substantially greater risk of default or can already be in default, and their values can decline significantly. Lower quality debt instruments are regarded as having predominantly speculative characteristics. Lower quality debt instruments tend to be more sensitive to adverse news about the issuer, or the market or economy in general, than higher quality debt instruments.

Geographic Focus Risk: The fund’s performance will be closely tied to the economic and political conditions in California, and can be more volatile than the performance of a more geographically diversified fund. In addition, the fund's performance can also be tied to the economic and political conditions of U.S. territories and possessions. These conditions may include constitutional or statutory limits on an issuer’s ability to raise revenues or increase taxes, anticipated or actual budget deficits or other financial difficulties, or changes in the credit quality of municipal issuers in the state or in U.S. territories and possessions.

Prepayment/Extension Risk: Instruments subject to prepayment and/or extension can reduce the potential for gain for the instrument’s holders if the instrument is prepaid and increase the potential for loss if the maturity of the instrument is extended.

Municipal Risk: The price of a municipal instrument can be volatile and significantly affected by adverse tax or court rulings, legislative or political changes, changes in specific or general market and economic conditions, and the financial condition of municipal issuers and insurers. Because many municipal instruments are issued to finance similar projects, conditions in these industries can significantly affect the fund and the overall municipal market.

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MFS California Municipal Bond Fund

Derivatives Risk: Derivatives can be highly volatile and involve risks in addition to the risks of the underlying indicator(s) on which the derivative is based. Gains or losses from derivatives can be substantially greater than the derivatives’ original cost. Derivatives can involve leverage.

Leveraging Risk: Leverage involves investment exposure in an amount exceeding the initial investment. Leverage can cause increased volatility by magnifying gains or losses.

Investment Selection Risk: The MFS analysis of an investment can be incorrect and can lead to an investment focus that results in the fund underperforming other funds with similar investment strategies and/or underperforming the markets in which the fund invests.

Counterparty and Third Party Risk: Transactions involving a counterparty or third party other than the issuer of the instrument are subject to the credit risk of the counterparty or third party, and to the counterparty’s or third party’s ability to perform in accordance with the terms of the transaction.

Liquidity Risk: It may not be possible to sell certain investments, types of investments, and/or segments of the market at any particular time or at an acceptable price.

The bar chart and performance table below are intended to provide some indication of the risks of investing in the fund by showing changes in the fund’s performance over time and how the fund’s performance over time compares with that of a broad measure of market performance.

The fund’s past performance (before and after taxes) does not necessarily indicate how the fund will perform in the future. Updated performance is available online at mfs.com or by calling 1-800-225-2606.

Class A Bar Chart. The bar chart does not take into account any sales charges (loads) that you may be required to pay upon purchase or redemption of the fund’s shares. If these sales charges were included, they would reduce the returns shown.

The total return for the six-month period ended June 30, 2011 was 4.25%. During the period(s) shown in the bar chart, the highest quarterly return was 10.24% (for the calendar quarter ended September 30, 2009) and the lowest quarterly return was (6.08)% (for the calendar quarter ended December 31, 2010).

Share Class	1 YEAR	5 YEARS	10 YEARS
Returns Before Taxes
B Shares	(3.79)%	1.56%	3.40%
C Shares	(1.03)%	1.75%	3.12%
A Shares	(3.95)%	1.68%	3.53%
Returns After Taxes on Distributions A Shares	(3.95)%	1.68%	3.52%
Returns After Taxes on Distributions and Sale of Fund Shares A Shares	(1.01)%	2.10%	3.70%
Index Comparison (Reflects no deduction for fees, expenses or taxes)
Barclays Capital Municipal Bond Index	2.38%	4.09%	4.83%

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your own tax situation, and may differ from those shown. The after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. The after-tax returns are shown for only one of the fund’s classes of shares, and after-tax returns for the fund’s other classes of shares will vary from the returns shown.

You may purchase and redeem shares of the fund each day the New York Stock Exchange is open for trading. You may purchase or redeem shares either by having your financial intermediary process your purchase or redemption, or by overnight mail (MFS Service Center, Inc. (MFSC), c/o Boston Financial Data Services, 30 Dan Road, Canton, MA 02021-2809), by mail ([Fund Name], P.O. Box 55824, Boston, MA 02205-5824), by telephone (1-800-225-2606), or via the Internet at mfs.com (MFS Access).

Class	Initial Minimum	Subsequent Minimum
Class A, Class B, Class C	None – automatic investment plans and certain asset-based fee programs $25 – employer-sponsored retirement plans $250 – Traditional and Roth IRAs $1,000 – other accounts	$50 – by check and non-systematic written exchange request, and via MFSC telephone representatives None – other purchases

If you purchase shares of the fund through a broker/dealer or other financial intermediary (such as a bank), the fund, MFS, and MFS’ affiliates may pay the financial intermediary for the sale of shares of a fund and/or the servicing of shareholder accounts. These payments may create a conflict of interest by influencing your broker/dealer or other financial intermediary and your salesperson to recommend the fund over another investment. Ask your financial intermediary or visit your financial intermediary’s Web site for more information.

CLASS	TICKER SYMBOL
Class A	MCFTX
Class B	MBCAX
Class C	MCCAX

Portfolio Manager	Since	Title
Michael L. Dawson	1999	Investment Officer of MFS