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 811-3327

MFS SERIES TRUST XIII

(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: February 29

Date of reporting period: May 31, 2008

ITEM 1. SCHEDULE OF INVESTMENTS.

MFS Diversified Income Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08

Issuer	Shares/Par		Value ($)
Bonds – 58.5%
Aerospace – 0.3%
Hawker Beechcraft Acquisition Co. LLC, 9.75%, 2017	$	360,000	$	369,000
Vought Aircraft Industries, Inc., 8%, 2011		305,000		295,087
			$	664,087
Agency - Other – 3.6%
Financing Corp., 9.4%, 2018	$	3,475,000	$	4,756,267
Financing Corp., 10.35%, 2018		1,415,000		2,055,000
Financing Corp., STRIPS, 0%, 2017		3,375,000		2,184,719
			$	8,995,986
Asset Backed & Securitized – 0.8%
Banc of America Commercial Mortgage, Inc., 5.39%, 2045	$	70,467	$	64,771
Banc of America Commercial Mortgage, Inc., FRN, 6.003%, 2017		145,867		135,405
Banc of America Commercial Mortgage, Inc., FRN, 5.772%, 2017		500,000		459,029
Citigroup Commercial Mortgage Trust, FRN, 5.7%, 2017		198,555		137,752
Credit Suisse Mortgage Capital Certificate, 5.343%, 2039		48,162		43,892
JPMorgan Chase Commercial Mortgage Securities Corp., 5.44%, 2045		237,347		218,466
JPMorgan Chase Commercial Mortgage Securities Corp., 5.372%, 2047		121,251		110,970
JPMorgan Chase Commercial Mortgage Securities Corp., FRN, 5.466%, 2047		189,579		171,698
Merrill Lynch/Countrywide Commercial Mortgage Trust, FRN, 5.204%, 2049		256,753		232,604
Merrill Lynch/Countrywide Commercial Mortgage Trust, FRN, 5.749%, 2050		66,000		61,033
Wachovia Bank Commercial Mortgage Trust, FRN, 5.752%, 2047		116,771		83,975
Wachovia Bank Commercial Mortgage Trust, FRN, 6.1%, 2051		256,150		238,895
			$	1,958,490
Automotive – 0.8%
Allison Transmission, Inc., 11%, 2015 (l)(n)	$	485,000	$	457,112
Ford Motor Credit Co. LLC, 9.75%, 2010		381,000		370,671
Ford Motor Credit Co. LLC, 12%, 2015		655,000		654,424
Ford Motor Credit Co. LLC, 8%, 2016		200,000		167,905
Ford Motor Credit Co. LLC, FRN, 4.283%, 2010		185,000		170,014
General Motors Acceptance Corp., 8.375%, 2033 (l)		400,000		274,000
			$	2,094,126
Broadcasting – 2.1%
Allbritton Communications Co., 7.75%, 2012	$	350,000	$	350,875
Bonten Media Acquisition Co., 9%, 2015 (n)(p)		285,000		220,875
CanWest MediaWorks LP, 9.25%, 2015 (n)		120,000		105,000
DIRECTV Holdings LLC, 7.625%, 2016 (z)		300,000		298,875
Grupo Televisa S.A., 8.5%, 2032		422,000		486,224
ION Media Networks, Inc., FRN, 8.963%, 2013 (n)		285,000		179,550
Lamar Media Corp., 6.625%, 2015		390,000		367,575
Lamar Media Corp., “C”, 6.625%, 2015		140,000		131,950
LBI Media, Inc., 8.5%, 2017 (n)		185,000		149,850
LIN TV Corp., 6.5%, 2013		1,150,000		1,091,062
Local TV Finance LLC, 9.25%, 2015 (n)(p)		445,000		358,225
Newport Television LLC, 13%, 2017 (z)(p)		415,000		375,575
Nexstar Broadcasting Group, Inc., 7%, 2014		310,000		274,350
Univision Communications, Inc., 9.75%, 2015 (n)(l)(p)		1,215,000		917,325
			$	5,307,311
Brokerage & Asset Managers – 0.2%
Nuveen Investments, Inc., 10.5%, 2015 (n)	$	450,000	$	423,000
Building – 0.4%
Associated Materials, Inc., 9.75%, 2012	$	90,000	$	89,550
Associated Materials, Inc., 0% to 2009, 11.25% to 2014 (l)		295,000		201,337
Building Materials Corp. of America, 7.75%, 2014		175,000		150,500
Nortek Holdings, Inc., 10%, 2013 (z)		145,000		144,094

1

MFS Diversified Income Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Issuer	Shares/Par		Value ($)
Bonds – continued
Building – continued
Nortek Holdings, Inc., 8.5%, 2014	$	240,000	$	168,000
Ply Gem Industries, Inc., 9%, 2012 (l)		500,000		343,750
			$	1,097,231
Business Services – 0.2%
SunGard Data Systems, Inc., 10.25%, 2015	$	507,000	$	527,280
Cable TV – 1.2%
CCH I Holdings LLC, 11%, 2015 (l)	$	205,000	$	174,250
CCH II Holdings LLC, 10.25%, 2010		405,000		402,975
CCO Holdings LLC, 8.75%, 2013		1,185,000		1,125,750
CSC Holdings, Inc., 6.75%, 2012		315,000		305,550
CSC Holdings, Inc., 8.5%, 2015 (z)		295,000		295,000
Mediacom LLC, 9.5%, 2013		380,000		362,900
NTL Cable PLC, 9.125%, 2016		300,000		294,000
			$	2,960,425
Chemicals – 1.0%
Braskem S.A., 7.25%, 2018 (z)	$	495,000	$	495,000
Innophos, Inc., 8.875%, 2014		615,000		627,300
Koppers Holdings, Inc., 9.875%, 2013		190,000		201,400
Momentive Performance Materials, Inc., 11.5%, 2016 (l)		540,000		457,650
Nalco Co., 8.875%, 2013		610,000		642,025
			$	2,423,375
Computer Software – 0.2%
First Data Corp., 9.875%, 2015 (n)	$	585,000	$	529,425
Consumer Goods & Services – 0.5%
Corrections Corp. of America, 6.25%, 2013	$	145,000	$	142,825
Jarden Corp., 7.5%, 2017		100,000		89,250
KAR Holdings, Inc., 10%, 2015		300,000		273,000
Service Corp. International, 7.375%, 2014		120,000		120,600
Service Corp. International, 7%, 2017		540,000		523,800
			$	1,149,475
Containers – 0.5%
Crown Americas LLC, 7.625%, 2013	$	190,000	$	195,700
Greif, Inc., 6.75%, 2017		570,000		567,150
Owens-Brockway Glass Container, Inc., 8.25%, 2013		450,000		465,750
			$	1,228,600
Defense Electronics – 0.2%
L-3 Communications Corp., 5.875%, 2015	$	450,000	$	426,375
Electronics – 0.2%
Flextronics International Ltd., 6.25%, 2014	$	250,000	$	238,750
Spansion LLC, 11.25%, 2016 (n)(l)		525,000		325,500
			$	564,250
Emerging Market Quasi-Sovereign – 3.5%
Codelco, Inc., 4.75%, 2014	$	979,000	$	959,115
Codelco, Inc., 5.625%, 2035		1,645,000		1,466,416
Gazprom International S.A., 7.201%, 2020		1,326,964		1,353,503
NAK Naftogaz Ukrainy, 8.125%, 2009		500,000		493,425
National Development Co., 6.369%, 2018 (z)		565,000		580,537
National Power Corp., 6.888%, 2011		381,000		403,358
National Power Corp., 6.875%, 2016 (n)		100,000		100,250
National Power Corp., 6.875%, 2016		300,000		300,750
Pemex Project Funding Master Trust, 5.75%, 2018 (n)		711,000		707,445
Pemex Project Funding Master Trust, 5.75%, 2018		485,000		482,575

2

MFS Diversified Income Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Issuer	Shares/Par		Value ($)
Bonds – continued
Emerging Market Quasi-Sovereign – continued
Pemex Project Funding Master Trust, 6.625%, 2035	$	1,882,000	$	1,900,434
			$	8,747,808
Emerging Market Sovereign – 8.8%
Banque Centrale de Tunisie, 7.375%, 2012	$	200,000	$	215,000
Federative Republic of Brazil, 6%, 2017		2,698,000		2,849,088
Federative Republic of Brazil, 8%, 2018		1,033,000		1,180,202
Gabonese Republic, 8.2%, 2017		700,000		738,500
Republic of Argentina, 7%, 2011		652,000		576,151
Republic of Argentina, 7%, 2013		174,638		138,498
Republic of Argentina, FRN, 3.092%, 2012		1,364,750		1,173,928
Republic of Colombia, 7.375%, 2017		729,000		824,499
Republic of Colombia, 7.375%, 2037		675,000		766,125
Republic of Croatia, FRN, 4%, 2010		568,182		567,176
Republic of El Salvador, 7.65%, 2035 (n)		225,000		239,625
Republic of El Salvador, 7.65%, 2035		200,000		213,000
Republic of Indonesia, 8.5%, 2035		1,265,000		1,365,249
Republic of Panama, 9.375%, 2029		1,387,000		1,870,369
Republic of Panama, 6.7%, 2036		816,000		852,720
Republic of Peru, 8.375%, 2016		202,000		242,400
Republic of Peru, 6.55%, 2037		802,000		842,100
Republic of Philippines, 9.375%, 2017		460,000		570,400
Republic of Philippines, 7.75%, 2031		575,000		636,812
Republic of Turkey, 7.375%, 2025		297,000		297,742
Republic of Turkey, 8%, 2034		85,000		88,876
Republic of Turkey, 6.875%, 2036		575,000		521,812
Republic of Ukraine, 6.75%, 2017		371,000		358,015
Republic of Uruguay, 9.25%, 2017		650,000		796,250
Republic of Uruguay, 8%, 2022		1,351,000		1,479,345
Republic of Uruguay, 7.625%, 2036		700,000		738,500
Russian Federation, 7.5%, 2030		683,658		778,413
United Mexican States, 6.75%, 2034		512,000		559,718
United Mexican States, 6.05%, 2040		466,000		459,010
			$	21,939,523
Energy - Independent – 1.4%
Chaparral Energy, Inc., 8.875%, 2017	$	175,000	$	155,312
Chesapeake Energy Corp., 6.875%, 2016		515,000		505,987
Forest Oil Corp., 7.25%, 2019		210,000		206,325
Forest Oil Corp., 7.25%, 2019 (z)		45,000		44,212
Hilcorp Energy I LP, 9%, 2016 (n)		340,000		352,750
Mariner Energy, Inc., 8%, 2017		345,000		333,787
OPTI Canada, Inc., 8.25%, 2014		395,000		406,850
Plains Exploration & Production Co., 7%, 2017		520,000		500,500
Plains Exploration & Production Co., 7.625%, 2018		155,000		155,775
Quicksilver Resources, Inc., 7.125%, 2016		295,000		287,625
SandRidge Energy, Inc., 8.625%, 2015 (z)(p)		115,000		118,162
SandRidge Energy, Inc., 8%, 2018 (z)		320,000		324,000
			$	3,391,285
Energy - Integrated – 0.3%
Petroleum Co. of Trinidad & Tobago Ltd., 6%, 2022 (n)	$	746,000	$	724,515
Entertainment – 0.0%
Marquee Holdings, Inc., 12%, 2014	$	120,000	$	96,600
Financial Institutions – 0.3%
General Motors Acceptance Corp., 6.875%, 2011	$	992,000	$	836,346

3

MFS Diversified Income Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Issuer	Shares/Par		Value ($)
Bonds – continued
Financial Institutions – continued
Residential Capital LLC, 8.5%, 2012	$	36,000	$	18,000
			$	854,346
Food & Beverages – 0.4%
ARAMARK Corp., 8.5%, 2015	$	485,000	$	496,519
Dean Foods Co., 7%, 2016		325,000		303,062
Del Monte Corp., 6.75%, 2015		300,000		290,250
			$	1,089,831
Forest & Paper Products – 0.7%
Buckeye Technologies, Inc., 8%, 2010	$	384,000	$	384,000
Catalyst Paper Corp., 8.625%, 2011		95,000		82,175
Georgia-Pacific Corp., 7.125%, 2017 (z)		165,000		162,937
Georgia-Pacific Corp., 8%, 2024		90,000		86,850
Graphic Packaging International Corp., 9.5%, 2013		125,000		125,937
Millar Western Forest Products Ltd., 7.75%, 2013		585,000		391,950
NewPage Holding Corp., 10%, 2012 (n)		515,000		548,475
Smurfit-Stone Container Corp., 8%, 2017		100,000		86,250
			$	1,868,574
Gaming & Lodging – 1.6%
Firekeepers Development Authority, 13.875%, 2015 (z)	$	270,000	$	270,675
Fontainebleau Las Vegas Holdings LLC, 10.25%, 2015 (n)		720,000		523,800
Harrah’s Operating Co., Inc., 10.75%, 2016 (n)		500,000		433,750
Harrah’s Operating Co., Inc., 5.75%, 2017		220,000		121,550
Harrah’s Operating Co., Inc., 10.75%, 2018 (n)(p)		455,000		359,450
MGM Mirage, 8.375%, 2011		200,000		198,250
MGM Mirage, 6.75%, 2013		750,000		678,750
Pinnacle Entertainment, Inc., 7.5%, 2015 (n)		235,000		193,875
Station Casinos, Inc., 6%, 2012		45,000		37,800
Station Casinos, Inc., 6.5%, 2014 (l)		645,000		406,350
Station Casinos, Inc., 6.875%, 2016		475,000		289,156
Trump Entertainment Resorts Holdings, Inc., 8.5%, 2015 (l)		765,000		518,287
			$	4,031,693
Industrial – 0.2%
Blount, Inc., 8.875%, 2012	$	280,000	$	284,200
JohnsonDiversey Holdings, Inc., 9.625%, 2012	EUR	75,000		114,337
JohnsonDiversey Holdings, Inc., 10.67%, 2013	$	240,000		240,000
			$	638,537
Insurance - Property & Casualty – 0.1%
USI Holdings Corp., 9.75%, 2015 (n)	$	280,000	$	226,800
Major Banks – 0.2%
JPMorgan Chase & Co., 7.9% to 2018, FRN to 2049	$	435,000	$	433,073
Medical & Health Technology & Services – 2.1%
Community Health Systems, Inc., 8.875%, 2015	$	560,000	$	577,500
Cooper Cos., Inc., 7.125%, 2015		230,000		220,225
DaVita, Inc., 7.25%, 2015		720,000		703,800
HCA, Inc., 6.375%, 2015		395,000		343,650
HCA, Inc., 9.25%, 2016		1,275,000		1,346,719
LVB Acquisition Merger Sub, Inc., 10%, 2017 (n)		385,000		412,913
LVB Acquisition Merger Sub, Inc., 11.625%, 2017 (n)		355,000		376,300
Psychiatric Solutions, Inc., 7.75%, 2015		190,000		194,750
U.S. Oncology, Inc., 10.75%, 2014		450,000		453,375
Universal Hospital Services, Inc., 8.5%, 2015 (p)		205,000		207,050
Universal Hospital Services, Inc., FRN, 8.287%, 2015		65,000		61,588

4

MFS Diversified Income Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Issuer	Shares/Par		Value ($)
Bonds – continued
Medical & Health Technology & Services – continued
VWR Funding, Inc., 10.25%, 2015 (p)	$	355,000	$	331,925
			$	5,229,795
Metals & Mining – 1.3%
FMG Finance Ltd., 10.625%, 2016 (n)	$	790,000	$	916,400
Foundation PA Coal Co., 7.25%, 2014		100,000		102,500
Freeport-McMoRan Copper & Gold, Inc., 8.375%, 2017		670,000		720,250
Freeport-McMoRan Copper & Gold, Inc., FRN, 5.883%, 2015		280,000		279,972
Peabody Energy Corp., 7.375%, 2016		105,000		107,363
Peabody Energy Corp., “B”, 6.875%, 2013		540,000		545,400
PNA Group, Inc., 10.75%, 2016		500,000		475,000
			$	3,146,885
Mortgage Backed – 14.5%
Fannie Mae, 4.35%, 2013	$	185,468	$	180,087
Fannie Mae, 4.374%, 2013		132,587		129,272
Fannie Mae, 4.518%, 2013		123,344		121,221
Fannie Mae, 5.549%, 2013		97,317		98,742
Fannie Mae, 4.559%, 2014		134,536		131,149
Fannie Mae, 4.775%, 2014		84,589		83,618
Fannie Mae, 4.871%, 2014		317,532		314,899
Fannie Mae, 4.88%, 2014		104,125		102,798
Fannie Mae, 4.935%, 2014		168,755		167,670
Fannie Mae, 4.56%, 2015		76,409		73,973
Fannie Mae, 4.6%, 2015		28,800		27,850
Fannie Mae, 4.69%, 2015		201,200		196,264
Fannie Mae, 4.7%, 2015		150,489		146,528
Fannie Mae, 4.78%, 2015		85,441		83,471
Fannie Mae, 4.79%, 2015		128,504		125,659
Fannie Mae, 4.81%, 2015		192,231		188,085
Fannie Mae, 4.85%, 2015		185,199		182,180
Fannie Mae, 4.856%, 2015		67,254		65,403
Fannie Mae, 4.86%, 2015		168,874		166,479
Fannie Mae, 4.925%, 2015		152,874		151,075
Fannie Mae, 5.034%, 2015		66,761		66,100
Fannie Mae, 5.09%, 2016		142,971		141,376
Fannie Mae, 5.395%, 2016		111,952		112,502
Fannie Mae, 5.423%, 2016		34,057		34,469
Fannie Mae, 5.845%, 2016		69,585		71,835
Fannie Mae, 5.93%, 2016		121,561		126,247
Fannie Mae, 4.996%, 2017		281,144		278,918
Fannie Mae, 5.05%, 2017		70,000		68,875
Fannie Mae, 5.06%, 2017		110,000		108,295
Fannie Mae, 5.28%, 2017		115,000		114,655
Fannie Mae, 5.3%, 2017		167,902		167,546
Fannie Mae, 5.32%, 2017		115,905		115,763
Fannie Mae, 5.38%, 2017		108,671		108,961
Fannie Mae, 5.45%, 2017		112,535		113,304
Fannie Mae, 5.5%, 2017 - 2038		10,741,368		10,713,181
Fannie Mae, 5.54%, 2017		190,000		192,317
Fannie Mae, 6%, 2017 - 2037		4,091,773		4,166,835
Fannie Mae, 6.5%, 2017 - 2037		349,496		361,213
Fannie Mae, 4.5%, 2018 - 2020		2,317,769		2,273,645
Fannie Mae, 5.19%, 2020		99,455		97,125
Fannie Mae, 5.35%, 2023		98,240		97,971
Fannie Mae, 5%, 2025 - 2028		1,910,087		1,933,246
Freddie Mac, 4.5%, 2015 - 2021		113,719		114,507

5

MFS Diversified Income Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Issuer	Shares/Par		Value ($)
Bonds – continued
Mortgage Backed – continued
Freddie Mac, 6%, 2017 - 2037		627,538	$	638,670
Freddie Mac, 5%, 2018 - 2027		3,767,678		3,797,702
Freddie Mac, 5.5%, 2022 - 2035		3,224,463		3,245,827
Freddie Mac, 4%, 2024		200,576		201,165
Freddie Mac, 6.5%, 2037		1,333,986		1,378,300
Ginnie Mae, 5.5%, 2033 - 2038		1,390,861		1,393,889
Ginnie Mae, 5.612%, 2058		340,000		337,875
Ginnie Mae, TBA, 5.5%, 2038		909,000		909,000
			$	36,217,737
Municipals – 1.0%
California Educational Facilities Authority Rev. (Stanford University), “T-1”, 5%, 2039	$	585,000	$	629,349
Clark County, NV School District, 5%, 2017		500,000		548,300
Commonwealth of Puerto Rico, ‘‘A’’, 5%, 2014 (c)		1,000,000		1,099,220
Minnesota Public Facilities Authority, Water Pollution Control Rev., “B”, 5%, 2018		310,000		340,563
			$	2,617,432
Natural Gas - Distribution – 0.4%
AmeriGas Partners LP, 7.125%, 2016	$	285,000	$	276,450
Inergy LP, 6.875%, 2014		820,000		791,300
			$	1,067,750
Natural Gas - Pipeline – 0.6%
Deutsche Bank (El Paso Performance-Linked Trust, CLN), 7.75%, 2011 (n)	$	375,000	$	385,755
El Paso Corp., 7.25%, 2018		190,000		190,713
Intergas Finance B.V., 6.875%, 2011		500,000		495,000
Transcapitalinvest, 5.67%, 2014		248,000		240,275
Williams Partners LP, 7.25%, 2017		175,000		178,938
			$	1,490,681
Network & Telecom – 0.9%
Cincinnati Bell, Inc., 8.375%, 2014	$	395,000	$	393,025
Citizens Communications Co., 9.25%, 2011		250,000		262,188
Nordic Telephone Co. Holdings, 8.875%, 2016 (n)		195,000		192,075
Qwest Capital Funding, Inc., 7.25%, 2011		985,000		962,838
Windstream Corp., 8.625%, 2016		385,000		397,994
			$	2,208,120
Other Banks & Diversified Financials – 0.0%
RSHB Capital S.A., 7.125%, 2014 (z)	$	100,000	$	100,620
Precious Metals & Minerals – 0.2%
Alrosa Finance S.A., 8.875%, 2014	$	482,000	$	523,500
Printing & Publishing – 1.0%
American Media Operations, Inc., 10.25%, 2009	$	14,726	$	12,370
American Media Operations, Inc., “B”, 10.25%, 2009 (l)		405,000		340,200
Dex Media West LLC, 9.875%, 2013		443,000		426,941
Dex Media, Inc., 0% to 2008, 9% to 2013		250,000		193,750
Idearc, Inc., 8%, 2016		591,000		422,565
Nielsen Co. B.V., 0% to 2011, 11.125% to 2016	EUR	115,000		116,281
Nielsen Finance LLC, 10%, 2014	$	575,000		592,969
Nielsen Finance LLC, 0% to 2011, 12.5% to 2016		25,000		18,125
Quebecor World, Inc., 6.125%, 2013 (l)(d)		120,000		59,400
R.H. Donnelley Corp., 8.875%, 2016		390,000		267,150
			$	2,449,751
Retailers – 0.1%
Couche-Tard, Inc., 7.5%, 2013	$	130,000	$	131,625
Sally Holdings LLC, 10.5%, 2016 (l)		55,000		53,625
			$	185,250

6

MFS Diversified Income Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Issuer	Shares/Par		Value ($)
Bonds – continued
Specialty Stores – 0.1%
Payless ShoeSource, Inc., 8.25%, 2013	$	170,000	$	152,150
Steel – 0.2%
Evraz Group S.A., 8.875%, 2013 (z)	$	620,000	$	632,400
Supermarkets – 0.1%
Stater Brothers Holdings, Inc., 7.75%, 2015	$	230,000	$	231,150
Telecommunications - Wireless – 0.8%
Alltel Corp., 7%, 2012	$	263,000	$	230,125
MetroPCS Wireless, Inc., 9.25%, 2014		315,000		302,794
Vimpel-Communications, 8.375%, 2013 (z)		562,000		572,546
Wind Acquisition Finance S.A., 10.75%, 2015 (n)		750,000		802,500
			$	1,907,965
Transportation - Services – 0.1%
Hertz Corp., 8.875%, 2014	$	180,000	$	179,100
U.S. Government Agencies – 1.5%
Freddie Mac, 5.4%, 2009	$	2,522,000	$	2,530,020
Small Business Administration, 5.16%, 2018		500,000		483,800
Small Business Administration, 6.34%, 2021		413,637		428,519
Small Business Administration, 6.07%, 2022		359,616		375,535
			$	3,817,874
U.S. Treasury Obligations – 1.8%
U.S. Treasury Bonds, 9.25%, 2016	$	47,000	$	63,792
U.S. Treasury Bonds, 6.75%, 2026 (l)		2,686,000		3,347,008
U.S. Treasury Bonds, 4.375%, 2038		130,000		123,195
U.S. Treasury Notes, 6.5%, 2010		53,000		56,428
U.S. Treasury Notes, 5.125%, 2011 (f)(l)		531,000		563,773
U.S. Treasury Notes, 4.125%, 2012 (l)		294,000		303,785
U.S. Treasury Notes, 4%, 2014 (l)		18,000		18,440
			$	4,476,421
Utilities - Electric Power – 2.1%
AES Corp., 9.375%, 2010	$	30,000	$	31,800
Centrais Eletricas Brasileiras S.A., 7.75%, 2015		418,000		452,485
Dynegy Holdings, Inc., 7.5%, 2015		180,000		170,100
Edison Mission Energy, 7%, 2017		430,000		420,325
Enersis S.A., 7.375%, 2014		450,000		476,297
Mirant Americas Generation LLC, 8.3%, 2011		600,000		622,500
Mirant North America LLC, 7.375%, 2013		135,000		136,013
NRG Energy, Inc., 7.375%, 2016		1,155,000		1,126,125
Reliant Energy, Inc., 6.75%, 2014		440,000		449,900
Reliant Energy, Inc., 7.875%, 2017		415,000		417,075
Sierra Pacific Resources, 8.625%, 2014		135,000		141,223
Texas Competitive Electric Holdings LLC, 10.25%, 2015 (n)		690,000		704,663
			$	5,148,506
Total Bonds			$	146,175,108
Floating Rate Loans – 1.9% (g)(r)
Aerospace – 0.1%
Hawker Beechcraft Acquisition Co., Letter of Credit, 4.7%, 2014	$	11,609	$	10,867
Hawker Beechcraft Acquisition Co., Term Loan B, 4.7%, 2014		299,087		279,973
			$	290,840
Automotive – 0.5%
Federal Mogul Corp., Term Loan B, 4.49%, 2015	$	229,020	$	195,812
Ford Motor Co., Term Loan B, 5.8%, 2013		879,640		757,773

7

MFS Diversified Income Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Issuer	Shares/Par		Value ($)
Floating Rate Loans (g)(r) – continued
Automotive – continued
Mark IV Industries, Inc., Second Lien Term Loan, 11.3%, 2011	$	300,597	$	121,742
			$	1,075,327
Broadcasting – 0.1%
Young Broadcasting, Inc., Term Loan, 5.23%, 2012	$	158,436	$	141,800
Young Broadcasting, Inc., Term Loan B-1, 5.25%, 2012		146,627		131,231
			$	273,031
Computer Software – 0.2%
First Data Corp., Term Loan B-2, 5.17%, 2014	$	593,644	$	550,268
Forest & Paper Products – 0.1%
Abitibi-Consolidated, Inc., Term Loan, 11.5%, 2009	$	148,613	$	147,498
Gaming & Lodging – 0.3%
Green Valley Ranch Gaming LLC, Second Lien Term Loan, 5.89%, 2014 (o)	$	302,859	$	198,751
Harrahs Entertainment, Inc., Term Loan B-2, 5.92%, 2015		620,883		579,653
			$	778,404
Medical & Health Technology & Services – 0.2%
Community Health Systems, Inc., Delayed Draw Term Loan B, 2014 (q)	$	5,230	$	4,930
Community Health Systems, Inc., Term Loan, 4.83%, 2014		102,256		96,396
HCA, Inc., Term Loan B, 4.95%, 2013		432,370		406,594
			$	507,920
Printing & Publishing – 0.1%
Idearc, Inc., Term Loan B, 2014 (o)	$	24,624	$	20,456
Tribune Co., Term Loan B, 2014 (o)		347,940		257,186
			$	277,642
Specialty Stores – 0.0%
Michaels Stores, Inc., Term Loan B, 5.04%, 2013	$	83,135	$	72,244
Telecommunications - Wireless – 0.1%
Alltel Corp., Term Loan B-2, 2015 (o)	$	333,333	$	308,981
Utilities - Electric Power – 0.2%
Calpine Corp., Term Loan, 5.58%, 2009	$	215,817	$	208,735
TXU Corp. Term Loan B-3, 6.26%, 2014		279,535		262,693
			$	471,428
Total Floating Rate Loans			$	4,753,583
Common Stocks – 35.2%
Aerospace – 0.2%
Northrop Grumman Corp.		7,076	$	533,955
Apparel Manufacturers – 0.1%
Coach, Inc. (a)		7,420	$	269,346
Automotive – 0.1%
Goodyear Tire & Rubber Co. (a)		5,380	$	136,706
Biotechnology – 0.0%
Amgen, Inc. (a)		2,567	$	113,025
Broadcasting – 0.2%
Walt Disney Co.		13,949	$	468,686
Brokerage & Asset Managers – 0.6%
Goldman Sachs Group, Inc.		740	$	130,543
Lehman Brothers Holdings, Inc.		5,152		189,645
Merrill Lynch & Co., Inc.		4,450		195,444
Morgan Stanley		20,860		922,638
			$	1,438,270

8

MFS Diversified Income Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Issuer	Shares/Par	Value ($)
Common Stocks – continued
Cable TV – 0.2%
Comcast Corp., “A”	21,620	$	486,450
Chemicals – 0.4%
Dow Chemical Co.	14,024	$	566,570
PPG Industries, Inc.	7,470		470,834
		$	1,037,404
Computer Software - Systems – 0.6%
International Business Machines Corp.	11,440	$	1,480,679
Construction – 0.3%
Lennar Corp.	7,740	$	130,651
NVR, Inc. (a)	980		554,063
		$	684,714
Consumer Goods & Services – 0.4%
Kimberly-Clark Corp.	1,983	$	126,515
Procter & Gamble Co.	11,660		770,143
		$	896,658
Electrical Equipment – 0.6%
General Electric Co.	34,762	$	1,067,889
Rockwell Automation, Inc.	2,047		119,852
WESCO International, Inc. (a)	5,500		243,705
		$	1,431,446
Electronics – 0.3%
Intel Corp.	36,497	$	846,000
Energy - Independent – 0.2%
Apache Corp.	2,610	$	349,897
Stone Energy Corp. (a)	1,820		122,996
		$	472,893
Energy - Integrated – 3.1%
Chevron Corp.	25,185	$	2,497,093
ConocoPhillips	5,280		491,568
Exxon Mobil Corp.	32,150		2,853,634
Hess Corp.	9,590		1,177,748
Marathon Oil Corp.	11,870		609,999
		$	7,630,042
Food & Beverages – 0.3%
General Mills, Inc.	10,767	$	680,474
SYSCO Corp.	3,550		109,553
		$	790,027
Food & Drug Stores – 0.2%
CVS Caremark Corp.	14,380	$	615,320
Forest & Paper Products – 0.6%
Weyerhaeuser Co.	24,004	$	1,496,169
Gaming & Lodging – 0.2%
Royal Caribbean Cruises Ltd.	18,451	$	548,364
General Merchandise – 0.3%
Macy’s, Inc.	7,395	$	175,040
Wal-Mart Stores, Inc.	8,970		517,928
		$	692,968
Health Maintenance Organizations – 0.1%
WellPoint, Inc. (a)	4,190	$	233,886

9

MFS Diversified Income Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Issuer	Shares/Par	Value ($)
Common Stocks – continued
Insurance – 1.9%
Ace Ltd.	2,897	$	174,023
Allstate Corp.	7,570		385,616
Endurance Specialty Holdings Ltd.	8,690		292,505
Hartford Financial Services Group, Inc.	9,650		685,826
IPC Holdings Ltd.	13,980		397,032
MetLife, Inc.	11,442		686,863
Protective Life Corp.	3,090		129,718
Prudential Financial, Inc.	6,930		517,671
Travelers Cos., Inc.	27,310		1,360,311
XL Capital Ltd., “A”	6,060		211,555
		$	4,841,120
Machinery & Tools – 0.9%
Eaton Corp.	10,880	$	1,051,878
Ingersoll-Rand Co. Ltd., “A”	6,310		277,892
Timken Co.	28,726		1,052,233
		$	2,382,003
Major Banks – 2.0%
Bank of America Corp.	58,151	$	1,977,716
JPMorgan Chase & Co.	49,310		2,120,330
PNC Financial Services Group, Inc.	7,620		489,585
Regions Financial Corp.	16,589		295,616
		$	4,883,247
Medical & Health Technology & Services – 0.6%
Omnicare, Inc.	15,760	$	385,805
Tenet Healthcare Corp. (a)	204,939		1,209,140
		$	1,594,945
Metals & Mining – 0.6%
Allegheny Technologies, Inc.	2,132	$	159,900
Freeport-McMoRan Copper & Gold, Inc.	3,980		460,526
Nucor Corp.	5,071		379,311
Southern Copper Corp. (l)	1,493		164,573
United States Steel Corp.	1,700		293,607
		$	1,457,917
Natural Gas - Distribution – 0.1%
Energen Corp.	4,200	$	314,790
Natural Gas - Pipeline – 0.4%
El Paso Corp.	26,940	$	526,677
Williams Cos., Inc.	14,079		535,565
		$	1,062,242
Other Banks & Diversified Financials – 0.9%
Allied Capital Corp. (l)	16,520	$	328,087
American Capital Strategies Ltd. (l)	9,320		298,240
Citigroup, Inc.	40,793		892,959
New York Community Bancorp, Inc.	22,370		459,032
TCF Financial Corp.	11,120		183,702
		$	2,162,020
Pharmaceuticals – 1.5%
Bristol-Myers Squibb Co.	20,886	$	475,992
Eli Lilly & Co.	2,422		116,595
Johnson & Johnson	16,960		1,131,910
Merck & Co., Inc.	19,983		778,538
Pfizer, Inc.	49,410		956,578

10

MFS Diversified Income Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Issuer	Shares/Par	Value ($)
Common Stocks – continued
Pharmaceuticals – continued
Wyeth	6,090	$	270,822
		$	3,730,435
Printing & Publishing – 0.1%
Deluxe Corp.	5,690	$	128,196
Railroad & Shipping – 0.2%
Frontline Ltd. (l)	7,330	$	467,214
Real Estate – 13.4%
Alexandria Real Estate Equities, Inc., REIT	16,866	$	1,759,124
AvalonBay Communities, Inc., REIT	10,595		1,072,214
BRE Properties, Inc., REIT	25,190		1,220,707
Douglas Emmett, Inc., REIT	11,992		293,804
EastGroup Properties, Inc., REIT	25,885		1,230,314
Equity Residential, REIT	23,967		1,013,564
General Growth Properties, Inc., REIT	39,998		1,662,317
HCP, Inc., REIT	9,178		314,438
Highwoods Properties, Inc., REIT	41,822		1,505,592
Host Hotels & Resorts, Inc., REIT	69,071		1,187,330
Kimco Realty Corp., REIT	40,843		1,607,172
Lexington Corporate Properties Trust, REIT	87,177		1,359,089
Macerich Co., REIT	23,233		1,661,856
Medical Properties Trust, Inc., REIT	174,503		2,130,682
Nationwide Health Properties, Inc., REIT	20,704		706,628
Pennsylvania Real Estate Investment Trust, REIT	37,337		1,002,498
Plum Creek Timber Co., Inc., REIT	34,478		1,608,399
ProLogis, REIT	31,651		1,960,146
Public Storage, Inc., REIT	13,763		1,212,933
Regency Centers Corp., REIT	16,548		1,100,277
Simon Property Group, Inc., REIT	28,412		2,823,016
SL Green Realty Corp., REIT	20,660		2,059,802
Ventas, Inc., REIT	24,528		1,169,004
Vornado Realty Trust, REIT	17,486		1,708,907
		$	33,369,813
Restaurants – 0.4%
Darden Restaurants, Inc.	29,712	$	1,017,636
Specialty Stores – 0.1%
Advance Auto Parts, Inc.	4,770	$	192,231
Telephone Services – 1.4%
AT&T, Inc.	29,140	$	1,162,686
Citizens Communications Co.	12,210		142,369
Embarq Corp.	19,269		911,809
Qwest Communications International, Inc. (l)	93,090		451,487
Verizon Communications, Inc.	23,580		907,123
		$	3,575,474
Tobacco – 0.4%
Altria Group, Inc.	18,210	$	405,355
Philip Morris International, Inc.	13,700		721,442
		$	1,126,797
Utilities - Electric Power – 1.3%
American Electric Power Co., Inc.	11,751	$	497,420
Duke Energy Corp.	18,070		333,934
Edison International	14,620		778,223
FirstEnergy Corp.	8,990		707,603
FPL Group, Inc.	3,110		209,987

11

MFS Diversified Income Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Issuer	Shares/Par		Value ($)
Common Stocks – continued
Utilities - Electric Power – continued
NRG Energy, Inc. (a)		10,020	$	416,732
Public Service Enterprise Group, Inc.		7,420		328,409
			$	3,272,308
Total Common Stocks			$	87,881,396
Preferred Stocks – 0.2%
Brokerage & Asset Managers – 0.2%
Merrill Lynch Co., Inc., 8.625% (a)		20,475	$	509,213
Money Market Funds (v) – 4.5%
U.S. Treasury Obligations – 4.5%
MFS Institutional Money Market Portfolio, 2.45%, at Net Asset Value	$	11,279,180	$	11,279,180
Issuer/Expiration Date/Strike Price	Number of Contracts		Value ($)
Call Options Purchased – 0.0%
U.S. Treasury Future – June 08 @ $115 (a)		5	$	781
Issuer	Shares/Par		Value ($)
Collateral for Securities Loaned – 2.7%
Citigroup Global Markets, Inc., Repurchase Agreement, 2.3%, dated 5/30/08, due 6/02/08, total to be received $5,665,885 (secured by U.S. Treasury and Federal Agency obligations and Mortgage Backed securities in a jointly traded account), at Net Asset Value		5,664,799	$	5,664,799
Merrill Lynch Repurchase Agreement, 2.2%, dated 5/30/08, due 6/02/08, total to be received $1,000,183 (secured by U.S. Treasury and Federal Agency obligations and Mortgage Backed securities in a jointly traded account), at Net Asset Value		1,000,000		1,000,000
Total Collateral for Securities Loaned			$	6,664,799
Total Investments			$	257,264,060
Other Assets, Less Liabilities – (3.0)%				(7,537,444	)
Net Assets – 100.0%			$	249,726,616

(a) Non-income producing security.

(c) Refunded bond.

(d) Non-income producing security - in default.

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

(g) The rate shown represents a weighted average coupon rate on settled positions at period end unless otherwise indicated.

(l) All or a portion of this security is on loan.

(n) Securities exempt from registration under Rule 144A of the Securities Act of 1933. These securities may be sold in the ordinary course of business in transactions exempt from registration, normally to qualified institutional buyers. At period end, the aggregate value of these securities was $11,867,203, representing 4.8% of net assets.

(o) All or a portion of this position has not settled. Upon settlement date, interest rates will be determined.

(p) Payment-in-kind security.

(q) All or a portion of this position represents an unfunded loan commitment. The rate shown represents a weighted average coupon rate on the full position, including the unfunded loan commitment which has no current coupon rate.

(r) Remaining maturities of floating rate loans may be less than stated maturities shown as a result of contractual or optional prepayments by the borrower. Such prepayments cannot be predicted with certainty. These loans may be subject to restrictions on resale. Floating rate loans generally have rates of interest which are determined periodically by reference to a base lending rate plus a premium.

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

(z) Restricted securities are not registered under the Securities Act of 1933 and are subject to legal restrictions on resale. These securities generally may be resold in transactions exempt from registration or to the public if the securities are subsequently registered. Disposal of these securities may involve time-consuming negotiations and prompt sale at an acceptable price may be difficult. The fund holds the following restricted securities:

Restricted Securities	Acquisition Date	Cost		Current Market Value
Braskem S.A., 7.25%, 2018	5/29/08	$	490,679	$	495,000
CSC Holdings, Inc., 8.5%, 2015	5/28/08		295,000		295,000
DIRECTV Holdings LLC, 7.625%, 2016	5/07/08		300,000		298,875

12

MFS Diversified Income Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Restricted Securities	Acquisition Date	Cost		Current Market Value
Evraz Group S.A., 8.875%, 2013	4/25/08	$	629,168	$	632,400
Firekeepers Development Authority, 13.875%, 2015	4/22/08		261,252		270,675
Forest Oil Corp., 7.25%, 2019	5/19/08		45,112		44,212
Georgia-Pacific Corp., 7.125%, 2017	4/22/08 - 4/23/08		165,223		162,937
National Development Co., 6.369%, 2018	5/28/08		566,617		580,537
Newport Television LLC, 13%, 2017	5/05/08 - 5/16/08		370,381		375,575
Nortek Holdings, Inc., 10%, 2013	5/13/08		143,494		144,094
RSHB Capital S.A., 7.125%, 2014	5/21/08		100,000		100,620
SandRidge Energy, Inc., 8%, 2018	5/15/08		320,000		324,000
SandRidge Energy, Inc., 8.625%, 2015	5/07/08		119,572		118,162
Vimpel-Communications, 8.375%, 2013	4/24/08		562,000		572,546
Total Restricted Securities				$	4,414,633
% of Net Assets					1.8	%

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

CLN	Credit-Linked Note
FRN	Floating Rate Note. Interest rate resets periodically and may not be the rate reported at period end.
REIT	Real Estate Investment Trust
STRIPS	Separate Trading of Registered Interest and Principal of Securities
TBA	To Be Announced

Abbreviations indicate amounts shown in currencies other than the U.S. dollar. All amounts are stated in U.S. dollars unless otherwise indicated. A list of abbreviations is shown below:

EUR Euro

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

13

MFS Diversified Income Fund

Supplemental Information (Unaudited) 5/31/08

(1) Fair Value Disclosure

The fund adopted FASB Statement No. 157, Fair Value Measurements (the “Statement”) in this reporting period. This Statement provides a single definition of fair value, a hierarchy for measuring fair value and expanded disclosures about fair value measurements.

Various inputs are used in determining the value of the fund’s assets or liabilities carried at market value. These inputs are categorized into three broad levels. Level 1 includes 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, forwards, swap contracts and written options, which are valued at the unrealized appreciation/depreciation on the instrument. The following is a summary of the levels used as of May 31, 2008 in valuing the fund’s assets or liabilities carried at market value:

	Level 1			Level 2			Level 3		Total
Investments in Securities	$	99,670,571		$	157,593,489		$	—	$	257,264,060
Other Financial Instruments	$	(15,498	)	$	(1,437	)	$	—	$	(16,935	)

(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	$	262,751,230
Gross unrealized appreciation	$	5,767,468
Gross unrealized depreciation		(11,254,638	)
Net unrealized appreciation (depreciation)	$	(5,487,170	)

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

(3) Securities Lending Collateral

At May 31, 2008, the value of securities loaned was $9,194,874. These loans were collateralized by cash of $6,664,799 and U.S. Treasury obligations of $2,742,273.

(4) Derivative Contracts at 5/31/08

Forward Foreign Currency Exchange Contracts at 5/31/08

Type	Currency	Contracts to Deliver/Receive	Settlement Date Range	In Exchange For		Contracts at Value		Net Unrealized Appreciation (Depreciation)
Depreciation
SELL	EUR	100,793	6/30/2008	$	155,661	$	156,603	$	(942	)
SELL	EUR	28,830	6/30/2008		44,299		44,794		(495	)
								$	(1,437	)

14

MFS Diversified Income Fund

Supplemental Information (Unaudited) 5/31/08

Futures contracts outstanding at 5/31/08

Description	Contracts	Value		Expiration Date	Unrealized Appreciation (Depreciation)
U.S. Treasury Bond (Short)	24	$	2,724,000	Sep-08	$	(12,834	)
U.S. Treasury Note 2 yr (Long)	35		7,371,875	Sep-08		2,612
U.S. Treasury Note 5 yr (Long)	46		5,057,125	Sep-08		(8,786	)
U.S. Treasury Note 10 yr (Short)	25		2,810,156	Sep-08		3,510
					$	(15,498	)

At May 31, 2008, the fund had sufficient cash and/or other liquid securities to cover any commitments under these derivative contracts.

(5) Transactions in Underlying 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 transactions in securities which the fund assumes to be affiliated issuers during the three months ended May 31, 2008, is set forth below:

Underlying Funds	Beginning Shares/Par Amount	Acquisitions Shares/Par Amount		Dispositions Shares/Par Amount			Ending Shares/Par Amount
MFS Institutional Money Market Portfolio	6,652,415		30,326,428		(25,699,663	)		11,279,180
Underlying Funds	Realized Gain (Loss)	Capital Gain Distributions		Dividend Income			Ending Value
MFS Institutional Money Market Portfolio	—	$	—	$	69,657		$	11,279,180

15

MFS Government Securities Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08

Issuer	Shares/Par		Value ($)
Bonds – 98.6%
Agency - Other – 6.8%
Financing Corp., 10.7%, 2017	$	14,360,000	$	20,970,480
Financing Corp., 9.4%, 2018		11,750,000		16,082,343
Financing Corp., 9.8%, 2018		14,975,000		21,008,997
Financing Corp., 10.35%, 2018		15,165,000		22,024,084
Financing Corp., STRIPS, 0%, 2017		18,780,000		12,156,745
			$	92,242,649
Mortgage Backed – 54.4%
Fannie Mae, 4.35%, 2013	$	904,156	$	877,922
Fannie Mae, 4.374%, 2013		2,519,162		2,456,177
Fannie Mae, 4.5%, 2019		43,955,247		43,094,141
Fannie Mae, 4.518%, 2014		3,067,382		2,993,387
Fannie Mae, 4.543%, 2013		1,440,241		1,415,719
Fannie Mae, 4.56%, 2015		2,330,810		2,256,493
Fannie Mae, 4.6%, 2014		1,804,079		1,763,195
Fannie Mae, 4.62%, 2015		3,331,044		3,239,329
Fannie Mae, 4.665%, 2015		1,573,667		1,532,085
Fannie Mae, 4.666%, 2014		5,883,008		5,760,657
Fannie Mae, 4.69%, 2015		1,282,530		1,251,069
Fannie Mae, 4.7%, 2015		1,805,600		1,761,191
Fannie Mae, 4.73%, 2012		2,756,464		2,740,746
Fannie Mae, 4.74%, 2015		1,781,476		1,740,553
Fannie Mae, 4.77%, 2014		1,554,276		1,528,400
Fannie Mae, 4.78%, 2015		1,942,113		1,897,328
Fannie Mae, 4.786%, 2012		778,948		777,140
Fannie Mae, 4.79%, 2012 - 2015		13,260,028		13,304,107
Fannie Mae, 4.81%, 2015		1,672,410		1,636,340
Fannie Mae, 4.815%, 2015		1,968,000		1,928,259
Fannie Mae, 4.82%, 2014 - 2015		6,548,902		6,430,633
Fannie Mae, 4.839%, 2014		8,841,493		8,742,253
Fannie Mae, 4.845%, 2013		3,736,886		3,712,594
Fannie Mae, 4.85%, 2015		1,434,336		1,410,956
Fannie Mae, 4.87%, 2015		1,368,682		1,345,884
Fannie Mae, 4.871%, 2014		5,640,388		5,593,610
Fannie Mae, 4.88%, 2020		1,273,957		1,275,526
Fannie Mae, 4.89%, 2015		1,267,023		1,248,460
Fannie Mae, 4.92%, 2014		1,217,088		1,215,567
Fannie Mae, 4.925%, 2015		5,327,346		5,264,662
Fannie Mae, 4.935%, 2014		783,773		778,732
Fannie Mae, 4.996%, 2017		4,466,879		4,431,512
Fannie Mae, 5%, 2013 - 2027		46,153,074		46,420,015
Fannie Mae, 5.05%, 2017		1,897,000		1,866,506
Fannie Mae, 5.06%, 2013 - 2017		2,882,129		2,861,064
Fannie Mae, 5.09%, 2016		600,000		592,097
Fannie Mae, 5.1%, 2014		1,964,247		1,960,714
Fannie Mae, 5.19%, 2020		1,537,284		1,501,280
Fannie Mae, 5.3%, 2017		790,126		788,450
Fannie Mae, 5.369%, 2013		1,946,336		1,974,830
Fannie Mae, 5.38%, 2017		2,084,501		2,090,062
Fannie Mae, 5.423%, 2016		2,951,313		2,986,997
Fannie Mae, 5.471%, 2015		2,391,825		2,428,493
Fannie Mae, 5.5%, 2017 - 2038		203,576,024		203,323,085
Fannie Mae, 6%, 2017 - 2037		71,722,713		73,050,351
Fannie Mae, 6.5%, 2016 - 2036		23,660,488		24,545,904
Fannie Mae, 7.5%, 2024 - 2031		577,880		623,330

1

MFS Government Securities Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Issuer	Shares/Par		Value ($)
Bonds – continued
Mortgage Backed – continued
Freddie Mac, 3.75%, 2024	$	2,103,053	$	2,104,491
Freddie Mac, 4%, 2024		1,967,698		1,973,473
Freddie Mac, 4.375%, 2015		5,825,017		5,822,840
Freddie Mac, 4.5%, 2013 - 2021		4,627,457		4,647,491
Freddie Mac, 5%, 2016 - 2027		53,859,580		54,377,321
Freddie Mac, 5.5%, 2022 - 2035		67,648,138		67,832,399
Freddie Mac, 6%, 2017 - 2037		27,868,130		28,413,611
Freddie Mac, 6.5%, 2016 - 2037		11,620,514		12,011,222
Ginnie Mae, 5.5%, 2033 - 2038		31,835,787		31,901,470
Ginnie Mae, 5.612%, 2058		7,610,000		7,562,438
Ginnie Mae, TBA, 5.5%, 2038		18,617,000		18,617,000
			$	737,681,561
Municipals – 3.0%
California Educational Facilities Authority Rev. (Stanford University), “T-1”, 5%, 2039	$	12,420,000	$	13,361,560
Clark County, NV School District, 5%, 2017		9,115,000		9,995,509
Commonwealth of Puerto Rico, ‘‘A’’, 5%, 2014 (c)		5,960,000		6,551,351
Minnesota Public Facilities Authority, Water Pollution Control Rev., “B”, 5%, 2018		2,325,000		2,554,222
New Jersey State Turnpike Authority, 5.75%, 2010 (c)		6,915,000		7,281,841
			$	39,744,483
U.S. Government Agencies – 7.4%
Aid-Egypt, 4.45%, 2015	$	7,118,000	$	7,117,573
Empresa Energetica Cornito Ltd., 6.07%, 2010		3,889,000		4,049,888
Farmer Mac, 5.5%, 2011 (n)		11,110,000		11,661,012
Federal Home Loan Bank, 5%, 2008		15,000,000		15,039,405
Small Business Administration, 4.77%, 2024		4,596,922		4,496,662
Small Business Administration, 4.86%, 2024 - 2025		7,970,335		7,816,088
Small Business Administration, 4.88%, 2024		2,720,462		2,655,420
Small Business Administration, 4.89%, 2023		5,816,186		5,685,636
Small Business Administration, 4.98%, 2023		2,236,773		2,217,385
Small Business Administration, 4.99%, 2024		4,135,937		4,056,524
Small Business Administration, 5.11%, 2025		4,140,968		4,093,037
Small Business Administration, 5.52%, 2024		3,610,214		3,671,472
Small Business Administration, 6.07%, 2022		2,609,782		2,725,311
Small Business Administration, 6.34%, 2021		2,688,638		2,785,371
Small Business Administration, 6.35%, 2021		2,353,610		2,438,185
Small Business Administration, 6.44%, 2021		2,578,348		2,677,621
Small Business Administration, 6.625%, 2021		2,825,892		2,974,989
Small Business Administration, 8.625%, 2011		93,823		95,762
Small Business Administration, 8.8%, 2011		68,610		70,380
Small Business Administration, 9.05%, 2009		10,349		10,554
Small Business Administration, 9.1%, 2009		7,999		8,218
Small Business Administration, 9.25%, 2010		29,797		30,337
Small Business Administration, 9.3%, 2010		64,334		66,208
Small Business Administration, 9.5%, 2010		49,980		51,289
Small Business Administration, 9.65%, 2010		39,301		40,461
Small Business Administration, 9.7%, 2010		29,743		30,508
Small Business Administration, 9.9%, 2008		3,360		3,413
Small Business Administration, 10.05%, 2008 - 2009		2,374		2,422
U.S. Department of Housing & Urban Development, 6.36%, 2016		7,000,000		7,400,092
U.S. Department of Housing & Urban Development, 6.59%, 2016		6,599,000		6,638,264
			$	100,609,487
U.S. Treasury Obligations – 27.0%
U.S. Treasury Bonds, 7.5%, 2016	$	3,421,000	$	4,259,946
U.S. Treasury Bonds, 4.75%, 2017		2,555,000		2,688,739
U.S. Treasury Bonds, 6.25%, 2023		8,165,000		9,597,068

2

MFS Government Securities Fund

PORTFOLIO OF INVESTMENTS (Unaudited) 5/31/08 - continued

Issuer	Shares/Par		Value ($)
Bonds – continued
U.S. Treasury Obligations – continued
U.S. Treasury Bonds, 6.875%, 2025	$	1,307,000	$	1,641,306
U.S. Treasury Bonds, 6%, 2026		5,933,000		6,831,755
U.S. Treasury Bonds, 6.75%, 2026		49,895,000		62,173,860
U.S. Treasury Bonds, 6.25%, 2030		3,166,000		3,828,140
U.S. Treasury Bonds, 4.375%, 2038		14,722,000		13,951,392
U.S. Treasury Notes, 4.875%, 2009		65,154,000		67,088,292
U.S. Treasury Notes, 6%, 2009		4,566,000		4,760,055
U.S. Treasury Notes, 6.5%, 2010		10,339,000		11,007,809
U.S. Treasury Notes, 2.125%, 2010		20,559,000		20,374,298
U.S. Treasury Notes, 5.125%, 2011 (f)		78,741,000		83,600,816
U.S. Treasury Notes, 4.125%, 2012		15,630,000		16,150,182
U.S. Treasury Notes, 3.375%, 2012		41,349,000		41,400,686
U.S. Treasury Notes, 4.25%, 2013		2,114,000		2,193,440
U.S. Treasury Notes, 4%, 2014		14,781,000		15,142,440
			$	366,690,224
Total Bonds			$	1,336,968,404
Money Market Funds (v) – 1.9%
MFS Institutional Money Market Portfolio, 2.45%, at Net Asset Value		26,399,266	$	26,399,266
Issuer/Expiration Date/Strike Price	Number of Contracts		Value ($)
Call Options Purchased – 0.0%
U.S. Treasury Future
June 2008 @ 115		118	$	18,438
Total Investments			$	1,363,386,108
Other Assets, Less Liabilities – (0.5)%				(6,733,482	)
Net Assets – 100.0%			$	1,356,652,626

(c) Refunded bond.

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

(n) Securities exempt from registration under Rule 144A of the Securities Act of 1933. These securities may be sold in the ordinary course of business in transactions exempt from registration, normally to qualified institutional buyers. At period end, the aggregate value of these securities was $11,661,012 representing 0.9% of net assets.

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

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

STRIPS	Separate Trading of Registered Interest and Principal of Securities
TBA	To Be Announced

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

3

MFS Government Securities Fund

Supplemental Information (Unaudited) 5/31/08

(1) Fair Value Disclosure

The fund adopted FASB Statement No. 157, Fair Value Measurements (the “Statement”) in this reporting period. This Statement provides a single definition of fair value, a hierarchy for measuring fair value and expanded disclosures about fair value measurements.

Various inputs are used in determining the value of the fund’s investments. These inputs are categorized into three broad levels. Level 1 includes 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, credit risk, etc.). 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, forwards, swap contracts and written options, which are valued at the unrealized appreciation/depreciation on the instrument. The following is a summary of the levels used as of May 31, 2008 in valuing the fund’s assets carried at market value:

	Level 1			Level 2		Level 3		Total
Investments in Securities	$	26,417,704		$	1,336,968,404	$	—	$	1,363,386,108
Other Financial Instruments	$	(265,974	)	$	—	$	—	$	(265,974	)

(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	$	1,356,593,274
Gross unrealized appreciation	$	17,146,270
Gross unrealized depreciation		(10,353,436	)
Net unrealized appreciation (depreciation)	$	6,792,834

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

(3) Derivative Contracts at 5/31/08

Futures contracts outstanding at 5/31/08

Description	Contracts	Value		Expiration Date	Unrealized Appreciation (Depreciation)
U.S. Treasury Bond 30 yr (Short)	252	$	28,467,243	Sep-08	$	(134,757	)
U.S. Treasury Note 5 yr (Long)	687		75,658,280	Sep-08		(131,217	)
					$	(265,974	)

At May 31, 2008, the fund had sufficient cash and/or other liquid securities to cover any commitments under these derivative contracts.

4

MFS Government Securities Fund

Supplemental Information (Unaudited) 5/31/08

(4) Transactions in Underlying 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 transactions in securities which the fund assumes to be affiliated issuers during the three months ended May 31, 2008, is set forth below:

Underlying Funds	Beginning Shares/Par Amount		Acquisitions Shares/Par Amount		Dispositions Shares/Par Amount			Ending Shares/Par Amount
MFS Institutional Money Market Portfolio		36,523,941		115,595,247		(125,719,922	)		26,399,266
Underlying Funds	Realized Gain (Loss)		Capital Gain Distributions		Dividend Income			Ending Value
MFS Institutional Money Market Portfolio	$	—	$	—	$	234,584		$	26,399,266

5

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 Amended and Restated 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 SERIES TRUST XIII

By (Signature and Title)*	ROBERT J. MANNING
	Robert J. Manning, President

Date:  July 17, 2008

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)*	ROBERT J. MANNING
	Robert J. Manning, President (Principal Executive Officer)

Date:  July 17, 2008

By (Signature and Title)*	MARIA F. DWYER
	Maria F. Dwyer, Treasurer (Principal Financial Officer and Accounting Officer)

Date:  July 17, 2008

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