MFS Total Return Fund

S000002439MFS Series Trust VCIK 0000200489

Share classes

9 classes of this one portfolio · 0 exchange-listed

Class ID	Symbol	Status	Security in the master	Type
C000006555	MSFFX	NOT_LISTED	not exchange-listed	—
C000006558	MSFHX	NOT_LISTED	not exchange-listed	—
C000006547	MSFJX	NOT_LISTED	not exchange-listed	—
C000116934	MSFKX	NOT_LISTED	not exchange-listed	—
C000006546	MSFRX	NOT_LISTED	not exchange-listed	—
C000006551	MTRBX	NOT_LISTED	not exchange-listed	—
C000006552	MTRCX	NOT_LISTED	not exchange-listed	—
C000006553	MTRIX	NOT_LISTED	not exchange-listed	—
C000006557	MTRRX	NOT_LISTED	not exchange-listed	—

The share-class bridge is a snapshot, not history. The SEC's fund share-class file says what each class trades as today, not what it traded as at a past report date. A fund that changed ticker or converted from a mutual fund resolves to its present-day symbol for every historical month shown.

Share classes

Report period

1 period filed. Holdings below describe the selected month only.

2026-03-31

Filing

NPORT-P · filed 2026-05-26

Report date: 2026-03-31
Net assets: $7,465,973,116.85
Total assets: $7,550,019,626.21
Total liabilities: $84,046,509.36
Assets invested: $0
Cash not reported in C or D: $0
Amendment: No
Accession: 0002071691-26-011425

By asset category

N-PORT Item C.4.a

ECEquity - common$4.33B57.7%

DBTDebt$1.78B23.7%

ABS-MBSAsset-backed: mortgage-ba…$872.51M11.6%

ABS-CBDOAsset-backed: collaterali…$346.43M4.6%

By asset category

By issuer category

N-PORT Item C.4.b

CORPCorporate$5.88B78.3%

USTUS Treasury$789.20M10.5%

USGSEUS government sponsored e…$489.37M6.5%

USGAUS government agency$196.86M2.6%

RFRegistered fund$127.59M1.7%

MUNMunicipal$26.89M0.4%

NUSSNon-US sovereign$2.38M0.0%

OTHEROther; the filer describe…-$4.77M-0.1%

By issuer category

By investment country

as filed

USUS$6.00B80.4%

IEIE$479.57M6.4%

KYKY$285.70M3.8%

CHCH$148.00M2.0%

GBGB$143.28M1.9%

JEJE$86.92M1.2%

CACA$77.11M1.0%

NLNL$60.89M0.8%

BMBM$57.87M0.8%

DEDE$52.93M0.7%

JPJP$45.40M0.6%

HKHK$21.83M0.3%

By country

Classification look-through

Positions resolved to the master through ISIN, then rolled up through the taxonomy. 52.1% of reported value reaches a classification.

Not resolved to the master(887)$3.56B47.4%

Equity · Financials(16)$1.07B14.2%

Equity · Health Care(10)$767.29M10.2%

Equity · Information Technology(7)$377.00M5.0%

Equity · Industrials(10)$323.67M4.3%

Equity · Energy(5)$259.96M3.5%

Equity · Communication Services(4)$250.40M3.3%

Equity · Consumer Staples(6)$246.52M3.3%

Equity · Consumer Discretionary(6)$198.28M2.6%

Equity · Utilities(4)$187.53M2.5%

Equity · Materials(4)$139.69M1.9%

Equity(1)$91.95M1.2%

Resolved, not yet classified(1)$37.38M0.5%

Classification covers part of the master. 5,771 of 13,106 active securities are classified. Anything unclassified is shown as its own band rather than dropped, so a look-through total that falls short of 100% is telling you about coverage, not about the fund.

Percentages are of the reported value of positions above ($7.51B), not of the fund’s net assets ($7.47B). The two differ by cash, derivatives filed with no market value, and rounding.

Issuer↕	In master	CUSIP / ISIN	Asset	Balance↕	Value↕	Weight▲	Country
Morgan Stanley Residential Mortgage Loan Trust Morgan Stanley Residential Mortgage Loan Trus…	—	617955AB5 US617955AB52	ABS-MBS CORP	5,098,142 PA	$5.08M	0.068%	US
HCA, Inc.	—	404119BY4 US404119BY43	DBT CORP	5,387,000 PA	$5.08M	0.068%	US
Santander Drive Auto Receivables Trust Santander Drive Auto Receivables Trust, Serie…	—	80288FAB7 US80288FAB76	ABS-O CORP	5,108,000 PA	$5.11M	0.068%	US
GNMA	—	21H032647 US21H0326478	ABS-MBS USGA	5,600,000 PA	$5.14M	0.069%	US
Duke Energy Progress LLC	—	26442UAH7 US26442UAH77	DBT CORP	5,272,000 PA	$5.16M	0.069%	US
Philip Morris International, Inc.	—	718172DA4 US718172DA46	DBT CORP	5,093,000 PA	$5.20M	0.070%	US
Magna International, Inc.	—	559222AV6 US559222AV67	DBT CORP	5,772,000 PA	$5.29M	0.071%	CA
Verizon Communications, Inc.	—	92343VDR2 US92343VDR24	DBT CORP	5,693,000 PA	$5.31M	0.071%	US
FNMA UMBS	—	3140XMWM4 US3140XMWM40	ABS-MBS USGSE	5,270,338.82 PA	$5.31M	0.071%	US
Brazos Securitization LLC	—	106230AB1 US106230AB12	DBT CORP	5,403,000 PA	$5.36M	0.072%	US
FNMA UMBS	—	31418EBR0 US31418EBR09	ABS-MBS USGSE	6,693,901.54 PA	$5.42M	0.073%	US
Brixmor Operating Partnership LP	—	11120VAJ2 US11120VAJ26	DBT CORP	5,578,000 PA	$5.43M	0.073%	US
FNMA UMBS	—	3140BCVV1 US3140BCVV14	ABS-MBS USGSE	5,331,496.71 PA	$5.44M	0.073%	US
Verisk Analytics, Inc.	—	92345YAH9 US92345YAH99	DBT CORP	5,258,000 PA	$5.44M	0.073%	US
Equinix, Inc.	—	29444UBS4 US29444UBS42	DBT CORP	6,102,000 PA	$5.45M	0.073%	US
JPMorgan Chase & Co.	—	46647PCU8 US46647PCU84	DBT CORP	6,063,000 PA	$5.50M	0.074%	US
FNMA UMBS	—	31418EBJ8 US31418EBJ82	ABS-MBS USGSE	6,373,301.17 PA	$5.53M	0.074%	US
GNMA	—	36179XHV1 US36179XHV10	ABS-MBS USGA	6,269,929.73 PA	$5.61M	0.075%	US
NTT Finance Corp.	—	62954WAV7 US62954WAV72	DBT CORP	5,588,000 PA	$5.67M	0.076%	JP
Neuberger Berman CLO XX Ltd. Neuberger Berman CLO XX Ltd., Series 2015-20A…	—	64130TBJ3 US64130TBJ34	ABS-CBDO CORP	5,725,000 PA	$5.71M	0.076%	KY
GNMA	—	36179TQN8 US36179TQN80	ABS-MBS USGA	6,391,539.5 PA	$5.78M	0.077%	US
FNMA UMBS	—	3140XGQ36 US3140XGQ365	ABS-MBS USGSE	6,711,837.5 PA	$5.90M	0.079%	US
Alimentation Couche-Tard, Inc.	—	01626PAP1 US01626PAP18	DBT CORP	7,513,000 PA	$5.92M	0.079%	CA
BSPRT Issuer Ltd. BSPRT Issuer Ltd., Series 2022-FL8, Class B	—	055983AE0 US055983AE09	ABS-CBDO CORP	5,979,000 PA	$5.96M	0.080%	KY
Intercontinental Exchange, Inc.	—	45866FAK0 US45866FAK03	DBT CORP	6,569,000 PA	$5.97M	0.080%	US
GNMA	—	36179XLG9 US36179XLG96	ABS-MBS USGA	6,180,818.05 PA	$6.02M	0.081%	US
FHLMC Pool UMBS	—	3132DWE66 US3132DWE664	ABS-MBS USGSE	6,215,846.64 PA	$6.02M	0.081%	US
T-Mobile USA, Inc.	—	87264AAZ8 US87264AAZ84	DBT CORP	7,504,000 PA	$6.06M	0.081%	US
GNMA	—	36179XHX7 US36179XHX75	ABS-MBS USGA	6,434,542.66 PA	$6.10M	0.082%	US
Plains All American Pipeline LP	—	72650RBN1 US72650RBN17	DBT CORP	6,329,000 PA	$6.10M	0.082%	US
FHLMC Pool UMBS	—	3142J6BU6 US3142J6BU67	ABS-MBS USGSE	6,025,003.68 PA	$6.14M	0.082%	US
T-Mobile USA, Inc.	—	87264ACA1 US87264ACA16	DBT CORP	6,433,000 PA	$6.17M	0.083%	US
FNMA UMBS	—	31418ECY4 US31418ECY41	ABS-MBS USGSE	7,122,307.6 PA	$6.17M	0.083%	US
Voya Ltd. Voya Ltd., Series 2012-4A, Class A2R3	—	92916GBF0 US92916GBF00	ABS-CBDO CORP	6,178,036.74 PA	$6.18M	0.083%	KY
Walt Disney Co. (The)	—	254687FY7 US254687FY73	DBT CORP	7,611,000 PA	$6.23M	0.083%	US
JPMorgan Chase & Co.	—	46647PBM7 US46647PBM77	DBT CORP	8,178,000 PA	$6.24M	0.084%	US
UBS Group AG	—	902613BH0 US902613BH06	DBT CORP	6,119,000 PA	$6.27M	0.084%	CH
FHLMC Pool UMBS	—	3132DWDS9 US3132DWDS98	ABS-MBS USGSE	7,130,569.45 PA	$6.28M	0.084%	US
Philip Morris International, Inc.	—	718172CX5 US718172CX57	DBT CORP	5,979,000 PA	$6.29M	0.084%	US
Pacific Gas and Electric Co.	—	694308JG3 US694308JG36	DBT CORP	7,060,000 PA	$6.33M	0.085%	US
GNMA	—	36179XNF9 US36179XNF95	ABS-MBS USGA	6,418,592.36 PA	$6.38M	0.086%	US
GNMA	—	36179W7K8 US36179W7K87	ABS-MBS USGA	7,154,843.86 PA	$6.39M	0.086%	US
GNMA GNMA, Series 2026-26, Class GF	—	38385NFG4 US38385NFG43	ABS-MBS USGA	6,420,064.37 PA	$6.41M	0.086%	US
GNMA	—	36179WVT2 US36179WVT25	ABS-MBS USGA	7,832,095.79 PA	$6.47M	0.087%	US
United States of America U.S. Treasury Bonds	—	912810TL2 US912810TL26	DBT UST	7,700,000 PA	$6.62M	0.089%	US
Enterprise Fleet Financing LLC Enterprise Fleet Financing LLC, Series 2026-1…	—	29376JAB9 US29376JAB98	ABS-O CORP	6,746,000 PA	$6.73M	0.090%	US
Benchmark Mortgage Trust Benchmark Mortgage Trust, Series 2025-V18, Cl…	—	08164EAC8 US08164EAC84	ABS-MBS CORP	6,657,910 PA	$6.78M	0.091%	US
Rhode Island Student Loan Authority	—	762323CU5 US762323CU56	DBT MUN	6,600,000 PA	$6.80M	0.091%	US
Aon Corp.	—	037389BB8 US037389BB82	DBT CORP	6,796,000 PA	$6.83M	0.091%	US
Avolon Holdings Funding Ltd.	—	05401AAJ0 US05401AAJ07	DBT CORP	6,935,000 PA	$6.86M	0.092%	KY