N-Q

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-Q

QUARTERLY SCHEDULE OF PORTFOLIO HOLDINGS OF

REGISTERED MANAGEMENT INVESTMENT COMPANIES

Investment Company Act file number 811-09537

MFS CALIFORNIA MUNICIPAL FUND

(Exact name of registrant as specified in charter)

500 Boylston Street, Boston, Massachusetts 02116

(Address of principal executive offices) (Zip code)

Susan S. Newton

Massachusetts Financial Services Company

500 Boylston Street

Boston, Massachusetts 02116

(Name and address of agents for service)

Registrant’s telephone number, including area code: (617) 954-5000

Date of fiscal year end: November 30

Date of reporting period: February 29, 2012

ITEM 1. SCHEDULE OF INVESTMENTS.

MFS^® California Municipal Fund

QUARTERLY REPORT

February 29, 2012

PORTFOLIO OF INVESTMENTS

2/29/12 (unaudited)

The Portfolio of Investments is a complete list of all securities owned by your fund. It is categorized by broad-based asset classes.

Issuer	Shares/Par		Value ($)
Municipal Bonds - 168.6%
Airport Revenue - 7.9%
Los Angeles, CA, Department of Airports Rev. (Los Angeles International), “C”, BHAC, 5.25%, 2038	$	750,000	$	819,856
Orange County, CA, Airport Rev., “A”, 5%, 2031		190,000		207,490
San Diego County, CA, Regional Airport Authority Rev., “A”, 5%, 2021		500,000		596,690
San Francisco, CA, City & County Airports Commission, International Airport Rev., “A”, 5%, 2030		285,000		311,066
San Francisco, CA, City & County Airports Commission, International Airport Rev., “A”, 5%, 2031		150,000		162,542
San Jose, CA, Airport Rev., “A-2”, 5.25%, 2034		440,000		474,976
			$	2,572,620
General Obligations - General Purpose - 11.2%
Commonwealth of Puerto Rico, “A”, 5.5%, 2018	$	370,000	$	421,293
Commonwealth of Puerto Rico, “A”, NATL, 5.5%, 2020		435,000		489,297
State of California, AMBAC, 6%, 2017		1,000,000		1,223,720
State of California, 5%, 2019		300,000		363,003
State of California, 5.5%, 2040		630,000		694,978
State of California, 5.25%, 2040		415,000		451,981
			$	3,644,272
General Obligations - Schools - 23.5%
Alhambra, CA, Unified School District, “B”, ASSD GTY, 5.25%, 2028	$	500,000	$	563,230
Banning, CA, Unified School District (Election of 2006), “B”, ASSD GTY, 5.25%, 2033		500,000		544,120
Chabot-Las Positas, CA, Community College (Election of 2004), “B”, AMBAC, 5%, 2030		60,000		64,480
Lake Tahoe, CA, Unified School District (Election of 2008), Capital Appreciation, AGM, 0%, 2045		515,000		180,240
Montebello, CA, Unified School District (Election of 2004), “A-1”, ASSD GTY, 5.25%, 2034		355,000		389,623
Napa Valley, CA, Unified School District, 5%, 2020		225,000		273,679
Peralta, CA, Community College District, AGM, 5%, 2016		500,000		580,590
Pittsburg, CA, Unified School District, “B”, AGM, 5.5%, 2034		500,000		549,995
Pomona, CA, Unified School District, “A”, NATL, 6.55%, 2029		1,000,000		1,255,210
San Diego, CA, Community College (Election of 2002), 5.25%, 2033		125,000		144,176
San Joaquin, CA, Delta Community College District (Election of 2004), “B”, Capital Appreciation, AGM, 0.00%, 2018		400,000		334,104
Vallejo City, CA, Unified School District, “A”, NATL, 5.9%, 2025		500,000		533,310
Victor, CA, Elementary School District (Election of 2008), “A”, ASSD GTY, 5.125%, 2034		500,000		539,715
Washington, CA, Yolo County Unified School District (New High School Project), 5%, 2021		450,000		479,997
West Contra Costa, CA, Unified School District, “A”, NATL, 5.7%, 2023		500,000		608,120
West Covina, CA, Unified School District, “A”, NATL, 5.8%, 2021		500,000		583,900
			$	7,624,489
Healthcare Revenue - Hospitals - 21.6%
ABAG Finance Authority for Non-Profit Corps, CA, Rev. (Sharp Healthcare), 6.25%, 2039	$	505,000	$	579,972
ABAG Finance Authority for Non-Profit Corps, CA, Rev. (Sharp Healthcare), “A”, 5%, 2026		110,000		122,142
California Health Facilities Financing Authority Rev. (Cedars-Sinai Medical Center), 5%, 2034		250,000		258,233
California Health Facilities Financing Authority Rev. (Scripps Health), “A”, 5%, 2032		150,000		167,310
California Health Facilities Financing Authority Rev. (Scripps Health), “A”, 5%, 2040		255,000		273,827
California Health Facilities Financing Authority Rev. (Sutter Health), “B”, 5.5%, 2020		500,000		623,025
California Health Facilities Financing Authority Rev. (Sutter Health), “B”, 5.875%, 2031		500,000		596,645
California Municipal Finance Authority, COP (Community Hospitals of Central California), 5.25%, 2027		250,000		256,943
California Statewide Communities Development Authority Rev. (Adventist), ASSD GTY, 5%, 2037		500,000		519,435
California Statewide Communities Development Authority Rev. (Catholic Healthcare West), “K”, ASSD GTY, 5.5%, 2041		1,000,000		1,048,720
California Statewide Communities Development Authority Rev. (Enloe Medical Center), “A”, CALHF, 5.5%, 2023		500,000		554,500
California Statewide Communities Development Authority Rev. (Huntington Memorial Hospital), 5%, 2035		535,000		543,961
California Statewide Communities Development Authority Rev. (Santa Ynez Valley Cottage Hospital), 5.25%, 2030		260,000		288,993
California Statewide Communities Development Authority Rev. (Trinity Health Corp.), 5%, 2041		450,000		486,729

1

Portfolio of Investments (unaudited) – continued

Issuer	Shares/Par		Value ($)
Municipal Bonds - continued
Healthcare Revenue - Hospitals - continued
Santa Clara County, CA, Financing Authority Rev. (El Camino Hospital), AMBAC, 5.125%, 2041	$	400,000	$	411,668
Upland, CA, COP (San Antonio Community Hospital), 6.375%, 2032		250,000		287,140
			$	7,019,243
Healthcare Revenue - Long Term Care - 3.6%
ABAG Finance Authority for Non-Profit Corps., CA, Rev. (Episcopal Senior Communities), 6.125%, 2041	$	150,000	$	157,086
ABAG Finance Authority for Non-Profit Corps., CA, Rev. (Odd Fellows Home), NATL, 6%, 2024		1,000,000		1,003,630
			$	1,160,716
Miscellaneous Revenue - Other - 1.8%
ABAG Finance Authority for Non-Profit Corps., CA, Rev. (Jackson Lab), 5.75%, 2037	$	385,000	$	405,821
California Infrastructure & Economic Development Bank Rev. (Walt Disney Family Museum), 5.25%, 2033		160,000		170,334
			$	576,155
Sales & Excise Tax Revenue - 2.1%
California Economic Recovery, “A”, 5%, 2020	$	250,000	$	302,738
Puerto Rico Sales Tax Financing Corp., Sales Tax Rev., Capital Appreciation, “A”, 0%, 2032		250,000		245,568
Puerto Rico Sales Tax Financing Corp., Sales Tax Rev., Capital Appreciation, “A”, AMBAC, 0%, 2054		1,625,000		134,664
			$	682,970
Single Family Housing - Local - 0.0%
California Rural Home Mortgage Finance Authority Rev., Mortgage Backed Securities Program, “A”, GNMA, 6.35%, 2029	$	5,000	$	5,095
California Rural Home Mortgage Finance Authority Rev., Mortgage Backed Securities Program, “B4”, FHA, 6.35%, 2029		5,000		5,157
			$	10,252
Single Family Housing - Other - 1.6%
California Department of Veterans Affairs, Home Purchase Rev., “A”, 4.5%, 2028	$	500,000	$	516,390
Single Family Housing - State - 7.5%
California Housing Finance Agency Rev. (Home Mortgage), “E”, 4.75%, 2030	$	305,000	$	284,367
California Housing Finance Agency Rev. (Home Mortgage), “G”, 4.95%, 2023		295,000		296,746
California Housing Finance Agency Rev. (Home Mortgage), “K”, 4.55%, 2021		775,000		762,747
California Housing Finance Agency Rev. (Home Mortgage), “K”, 5.3%, 2023		365,000		365,661
California Housing Finance Agency Rev. (Home Mortgage), “L”, 5.45%, 2033		555,000		556,915
California Housing Finance Agency Rev. (Home Mortgage), “L”, FNMA, 5.5%, 2038		165,000		165,155
			$	2,431,591
Solid Waste Revenue - 1.5%
Salinas Valley, CA, Solid Waste Authority Rev., AMBAC, 5.125%, 2022	$	500,000	$	501,605
State & Agency - Other - 1.4%
Sacramento County, CA, Public Facilities Project, COP, AMBAC, 4.75%, 2027	$	500,000	$	468,550
State & Local Agencies - 22.3%
Compton, CA, Public Finance Authority, AMBAC, 5%, 2032	$	500,000	$	403,060
Golden State, CA, Tobacco Securitization Corp., Tobacco Settlement Rev., FGIC, 5%, 2035		255,000		257,484
Golden State, CA, Tobacco Securitization Corp., Tobacco Settlement Rev., BHAC, 5%, 2038		1,000,000		1,017,260
Golden State, CA, Tobacco Securitization Corp., Tobacco Settlement Rev., Enhanced, “A”, FGIC, 5%, 2035		1,000,000		1,006,160
Golden State, CA, Tobacco Securitization Corp., Tobacco Settlement Rev., Enhanced, “A”, FGIC, 5%, 2038		1,000,000		1,003,180
Huntington Park, CA, Public Financing Authority Rev., “A”, AGM, 5.25%, 2019		500,000		548,520
Los Angeles County, CA, Schools Regionalized Business Service Corp., Pooled Financing, Capital Appreciation, “A”, AMBAC, 0%, 2018		2,020,000		1,446,684
Los Angeles County, CA, Schools Regionalized Business Service Corp., Pooled Financing, Capital Appreciation, “A”, AMBAC, 0%, 2023		2,220,000		1,117,459
Los Angeles, CA, Municipal Improvement Corp. Lease Rev., “B”, ASSD GTY, 5.5%, 2030		390,000		438,224
			$	7,238,031

2

Portfolio of Investments (unaudited) – continued

Issuer	Shares/Par		Value ($)
Municipal Bonds - continued
Tax Assessment - 11.4%
Fontana, CA, Public Finance Authority, Tax Allocation Rev. (Sub Lien North Fontana Redevelopment), “A”, AMBAC, 5%, 2029	$	1,000,000	$	1,008,090
Huntington Beach, CA, Community Facilities District, Special Tax (Grand Coast Resort), “2000-1”, 6.45%, 2031		100,000		101,140
Lancaster, CA, Financing Authority, Tax Allocation Rev. (Projects No. 5 & 6 Redevelopment Projects), NATL, 5.25%, 2020		825,000		828,663
San Diego, CA, Redevelopment Agency, Tax Allocation Rev. (Centre City), “A”, AMBAC, 5.25%, 2025		500,000		527,125
San Dieguito, CA, Public Facilities Authority, “A”, AMBAC, 5%, 2032		500,000		517,980
San Jose, CA, Redevelopment Agency, Tax Allocation (Merged Area Redevelopment Project), “C”, NATL, 4.25%, 2030		900,000		732,825
			$	3,715,823
Tobacco - 3.8%
Golden State, CA, Tobacco Securitization Corp., Tobacco Settlement Rev., “A-1”, 5.125%, 2047	$	1,000,000	$	684,410
Golden State, CA, Tobacco Securitization Corp., Tobacco Settlement Rev., “A-1”, 5.75%, 2047		715,000		547,154
			$	1,231,564
Toll Roads - 0.8%
Foothill/Eastern Corridor Agency, CA, Toll Road Rev., NATL, 5.125%, 2019	$	250,000	$	250,073
Transportation - Special Tax - 2.5%
Commonwealth of Puerto Rico Highway & Transportation Authority, Highway Rev., “K”, 5%, 2014	$	235,000	$	252,190
Commonwealth of Puerto Rico Highway & Transportation Authority, Highway Rev., “Y”, AGM, 5.5%, 2016 (c)		450,000		545,868
			$	798,058
Universities - Colleges - 7.8%
California Educational Facilities Authority Rev. (Dominican University of California), 5%, 2025	$	120,000	$	122,887
California Educational Facilities Authority Rev. (University of San Francisco), 6.125%, 2030		285,000		338,503
California Public Works Board Lease Rev. (The Regents of the University of California), 5%, 2028		375,000		430,740
California State University Rev., “A”, 5%, 2024		370,000		442,590
University Enterprises, Inc. (Auxiliary Organization), “A”, FGIC, 4.375%, 2030		500,000		503,190
University of California Rev., “U”, 5%, 2017		570,000		690,270
			$	2,528,180
Universities - Secondary Schools - 1.4%
California Statewide Communities Development Authority, School Facility Rev. (Alliance for College-Ready Public Schools), “A”, 6.1%, 2032	$	150,000	$	150,831
California Statewide Communities Development Authority, School Facility Rev. (Alliance for College-Ready Public Schools), “A”, 6.375%, 2047		315,000		316,830
			$	467,661
Utilities - Municipal Owned - 13.3%
California Department of Water Resources, Power Supply Rev., “L”, 5%, 2019	$	805,000	$	996,091
California Department of Water Resources, Power Supply Rev., “N”, 5%, 2020		205,000		255,252
Imperial Irrigation District Electric Rev., “A”, 5%, 2017		500,000		601,760
Los Angeles, CA, Department of Water & Power Rev., “A”, 5%, 2019		590,000		737,783
Northern California Power Agency, Capital Facilities Rev., “A”, 5.25%, 2024		390,000		446,616
Sacramento, CA, Municipal Utility District Rev., “U”, AGM, 5%, 2019		750,000		897,930
Vernon, CA, Electric System Rev., “A”, 5.5%, 2041		370,000		383,327
			$	4,318,759
Utilities - Other - 2.8%
California M-S-R Energy Authority Gas Rev., “A”, 6.5%, 2039	$	245,000	$	301,000
Southern California Public Power Authority (Natural Gas Project No. 1), “A”, 5%, 2033		585,000		591,154
			$	892,154
Water & Sewer Utility Revenue - 18.8%
Atwater, CA, Public Financing Authority Wastewater Rev., ASSD GTY, 5%, 2034	$	500,000	$	524,475
California Department of Water Resources (Center Valley Project), “A-E”, 5%, 2028		500,000		574,580
Chino Basin, CA, Regional Financing Authority Rev. (Inland Empire Utilities Agency), “A”, AMBAC, 5%, 2038 (f)		1,000,000		1,057,900
Commonwealth of Puerto Rico Aqueduct & Sewer Authority Rev., “A”, 5%, 2033		135,000		134,991
Commonwealth of Puerto Rico Aqueduct & Sewer Authority Rev., “A”, 5.125%, 2037		65,000		65,021

3

Portfolio of Investments (unaudited) – continued

Issuer	Shares/Par		Value ($)
Municipal Bonds - continued
Water & Sewer Utility Revenue - continued
Commonwealth of Puerto Rico Aqueduct & Sewer Authority Rev., “A”, 5.75%, 2037	$	75,000	$	79,798
Commonwealth of Puerto Rico Aqueduct & Sewer Authority Rev., “A”, 5.25%, 2042		35,000		35,053
Los Angeles, CA, Department of Water & Power Waterworks Rev., “C”, NATL, 5%, 2029		500,000		522,250
Madera, CA, Irrigation Financing Authority Rev., 6.5%, 2040		440,000		483,450
Norco, CA, Financing Authority Enterprise Rev., AGM, 5.625%, 2039		215,000		235,711
Sacramento, CA, Municipal Utility District, “X”, 5%, 2025		370,000		436,463
San Francisco, CA, City & County Public Utilities Commission Water Rev., “A”, 5%, 2023		445,000		557,242
San Francisco, CA, City & County Public Utilities Commission Water Rev., “A”, 5.25%, 2031		335,000		391,441
Sonoma County, CA, Water Agency Rev., “A”, AGM, 5%, 2036		600,000		635,784
Southern California Metropolitan Water District Rev., “A”, 5%, 2028		325,000		374,780
			$	6,108,939
Total Municipal Bonds			$	54,758,095
Money Market Funds - 6.6%
MFS Institutional Money Market Portfolio, 0.1%, at Net Asset Value (v)		2,152,749	$	2,152,749
Total Investments			$	56,910,844
Other Assets, Less Liabilities - 0.1%				27,100
Preferred shares (Issued by the Fund) - (75.3)%				(24,450,000	)
Net Assets applicable to common shares - 100.0%			$	32,487,944

(c) Refunded bond.

(f) All or a portion of the security has been segregated as collateral for open futures contracts.

(v) Underlying affiliated fund that is available only to investment companies managed by MFS. The rate quoted for the MFS Institutional Money Market Portfolio is the annualized seven-day yield of the fund at period end.

The following abbreviations are used in this report and are defined:

COP Certificate of Participation

Insurers
AGM	Assured Guaranty Municipal
AMBAC	AMBAC Indemnity Corp.
ASSD GTY	Assured Guaranty Insurance Co.
BHAC	Berkshire Hathaway Assurance Corp.
CALHF	California Housing Finance Agency
FGIC	Financial Guaranty Insurance Co.
FHA	Federal Housing Administration
FNMA	Federal National Mortgage Assn.
GNMA	Government National Mortgage Assn.
NATL	National Public Finance Guarantee Corp.

Derivative Contracts at 2/29/12

Futures Contracts Outstanding at 2/29/12

Description	Currency		Contracts		Value	Expiration Date		Unrealized Appreciation (Depreciation)
Liability Derivatives
Interest Rate Futures
U.S. Treasury Note 10 yr (Short)		USD		20	$2,619,063		June - 2012		$(850	)
U.S. Treasury Bond 30 yr (Short)		USD		4	566,625		June - 2012		(389	)
									$(1,239	)

At February 29, 2012, the fund had sufficient cash and/or other liquid securities to cover any commitments under these derivative contracts.

See attached supplemental information. For more information see notes to financial statements as disclosed in the most recent semiannual or annual report.

4

Supplemental Information

2/29/12 (unaudited)

(1) Investment Valuations

Debt instruments and floating rate loans (other than short-term instruments), including restricted debt instruments, are generally valued at an evaluated or composite bid as provided by a third-party pricing service. Short-term instruments with a maturity at issuance of 60 days or less generally are valued at amortized cost, which approximates market value. Futures contracts are generally valued at last posted settlement price as provided by a third-party pricing service on the market on which they are primarily traded. Futures contracts for which there were no trades that day for a particular position are generally valued at the closing bid quotation as provided by a third-party pricing service on the market on which such futures contracts are primarily traded. Open-end investment companies are generally valued at net asset value per share. Securities and other assets generally valued on the basis of information from a third-party pricing service may also be valued at a broker/dealer bid quotation. Values obtained from third-party pricing services can utilize both transaction data and market information such as yield, quality, coupon rate, maturity, type of issue, trading characteristics, and other market data.

The Board of Trustees has delegated primary responsibility for determining or causing to be determined the value of the fund’s investments (including any fair valuation) to the adviser pursuant to valuation policies and procedures approved by the Board. If the adviser determines that reliable market quotations are not readily available, investments are valued at fair value as determined in good faith by the adviser in accordance with such procedures under the oversight of the Board of Trustees. Under the fund’s valuation policies and procedures, market quotations are not considered to be readily available for most types of debt instruments and floating rate loans and many types of derivatives. These investments are generally valued at fair value based on information from third-party pricing services. In addition, investments may be valued at fair value if the adviser determines that an investment’s value has been materially affected by events occurring after the close of the exchange or market on which the investment is principally traded (such as foreign exchange or market) and prior to the determination of the fund’s net asset value, or after the halting of trading of a specific security where trading does not resume prior to the close of the exchange or market on which the security is principally traded. The adviser generally relies on third-party pricing services or other information (such as the correlation with price movements of similar securities in the same or other markets; the type, cost and investment characteristics of the security; the business and financial condition of the issuer; and trading and other market data) to assist in determining whether to fair value and at what value to fair value an investment. The value of an investment for purposes of calculating the fund’s net asset value can differ depending on the source and method used to determine value. When fair valuation is used, the value of an investment used to determine the fund’s net asset value may differ from quoted or published prices for the same investment. There can be no assurance that the fund could obtain the fair value assigned to an investment if it were to sell the investment at the same time at which the fund determines its net asset value per share.

Various inputs are used in determining the value of the fund’s assets or liabilities. These inputs are categorized into three broad levels. In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, an investment’s level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. The fund’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the investment. Level 1 includes unadjusted quoted prices in active markets for identical assets or liabilities. Level 2 includes other significant observable market-based inputs (including quoted prices for similar securities, interest rates, prepayment speed, and credit risk). Level 3 includes unobservable inputs, which may include the adviser’s own assumptions in determining the fair value of investments. Other financial instruments are derivative instruments not reflected in total investments, such as futures. The following is a summary of the levels used as of February 29, 2012 in valuing the fund’s assets or liabilities:

Investments at Value	Level 1			Level 2		Level 3		Total
Municipal Bonds		$—			$54,758,095		$—		$54,758,095
Mutual Funds		2,152,749			—		—		2,152,749
Total Investments		$2,152,749			$54,758,095		$—		$56,910,844
Other Financial Instruments
Futures		$(1,239	)		$—		$—		$(1,239	)

For further information regarding security characteristics, see the Portfolio of Investments.

5

Supplemental Information (unaudited) – continued

(2) Portfolio Securities

The cost and unrealized appreciation and depreciation in the value of the investments owned by the fund, as computed on a federal income tax basis, are as follows:

Aggregate cost	$54,104,437
Gross unrealized appreciation	$3,416,907
Gross unrealized depreciation	(610,500	)
Net unrealized appreciation (depreciation)	$2,806,407

The aggregate cost above includes prior fiscal year end tax adjustments, if applicable.

(3) Transactions in Underlying Affiliated Funds – Affiliated Issuers

An affiliated issuer may be considered one in which the fund owns 5% or more of the outstanding voting securities, or a company which is under common control. For the purposes of this report, the fund assumes the following to be affiliated issuers:

Underlying Affiliated Funds	Beginning Shares/Par Amount		Acquisitions Shares/Par Amount		Dispositions Shares/Par Amount			Ending Shares/Par Amount
MFS Institutional Money Market Portfolio		2,533,794		3,401,682		(3,782,727	)		2,152,749
Underlying Affiliated Funds	Realized Gain (Loss)		Capital Gain Distributions		Dividend Income			Ending Value
MFS Institutional Money Market Portfolio		$—		$—		$325			$2,152,749

6

ITEM 2. CONTROLS AND PROCEDURES.

(a) Based upon their evaluation of the effectiveness of the registrant’s disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940 (the “Act”)) as conducted within 90 days of the filing date of this Form N-Q, the registrant’s principal financial officer and principal executive officer have concluded that those disclosure controls and procedures provide reasonable assurance that the material information required to be disclosed by the registrant on this report is recorded, processed, summarized and reported within the time periods specified in the Securities and Exchange Commission’s rules and forms.

(b) There were no changes in the registrant’s internal controls over financial reporting (as defined in Rule 30a-3(d) under the Act) that occurred during the registrant’s last fiscal quarter that have materially affected, or are reasonably likely to materially affect, the registrant’s internal control over financial reporting.

ITEM 3. EXHIBITS.

File as exhibits as part of this Form a separate certification for each principal executive officer and principal financial officer of the registrant as required by Rule 30a-2(a) under the Act (17 CFR 270.30a-2): Attached hereto.

Notice

A copy of the Agreement and Declaration of Trust, as amended, of the Registrant is on file with the Secretary of State of The Commonwealth of Massachusetts and notice is hereby given that this instrument is executed on behalf of the Registrant by an officer of the Registrant as an officer and not individually and the obligations of or arising out of this instrument are not binding upon any of the Trustees or shareholders individually, but are binding only upon the assets and property of the respective constituent series of the Registrant.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Registrant: MFS CALIFORNIA MUNICIPAL FUND

By (Signature and Title)*	JOHN M. CORCORAN
	John M. Corcoran, President

Date: April 13, 2012

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By (Signature and Title)*	JOHN M. CORCORAN
	John M. Corcoran, President (Principal Executive Officer)

Date: April 13, 2012

By (Signature and Title)*	DAVID L. DILORENZO
	David L. DiLorenzo, Treasurer (Principal Financial Officer and Accounting Officer)

Date: April 13, 2012

* Print name and title of each signing officer under his or her signature.

EX-99.CERT

EX-99.CERT

MFS CALIFORNIA MUNICIPAL FUND

CERTIFICATION

I, David L. DiLorenzo, certify that:

1. I have reviewed this report on Form N-Q of MFS California Municipal Fund;

2. Based on my knowledge, this 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 report;

3. Based on my knowledge, the schedules of investments included in this report fairly present in all material respects the investments of the registrant as of the end of the fiscal quarter for which the report is filed;

4. The registrant’s other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940) and internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act of 1940) for the registrant 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 registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this 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 registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of a date within 90 days prior to the filing date of this report, based on such evaluation; and

d. Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer and I have disclosed to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a. All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize, and report financial information; and

b. Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: April 13, 2012	DAVID L. DILORENZO
	David L. DiLorenzo
	Treasurer (Principal Financial Officer and Accounting Officer)

EX-99.CERT

MFS CALIFORNIA MUNICIPAL FUND

CERTIFICATION

I, John M. Corcoran, certify that:

1. I have reviewed this report on Form N-Q of MFS California Municipal Fund;

2. Based on my knowledge, this 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 report;

3. Based on my knowledge, the schedules of investments included in this report fairly present in all material respects the investments of the registrant as of the end of the fiscal quarter for which the report is filed;

4. The registrant’s other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940) and internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act of 1940) for the registrant 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 registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this 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 registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of a date within 90 days prior to the filing date of this report, based on such evaluation; and

d. Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer and I have disclosed to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a. All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize, and report financial information; and

b. Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: April 13, 2012	JOHN M. CORCORAN
	John M. Corcoran
	President (Principal Executive Officer)