# EDGAR Filing Document

**Accession Number:** 0000783740
**File Stem:** 0001410368-26-007050
**Filing Date:** 2026-1
**Character Count:** 10456
**Document Hash:** b31409f92c1d4d346c7b697c50b319fb
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001410368-26-007050.hdr.sgml**: 20260126

**ACCESSION NUMBER**: 0001410368-26-007050

**CONFORMED SUBMISSION TYPE**: NPORT-P

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20251130

**FILED AS OF DATE**: 20260126

**DATE AS OF CHANGE**: 20260126

**PERIOD START**: 20260531

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MFS SERIES TRUST X
- **CENTRAL INDEX KEY:** 0000783740

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** MA
- **FISCAL YEAR END:** 1130

**FILING VALUES:**
- **FORM TYPE:** NPORT-P
- **SEC ACT:** 1940 Act
- **SEC FILE NUMBER:** 811-04492
- **FILM NUMBER:** 26558574

**BUSINESS ADDRESS:**
- **STREET 1:** 111 HUNTINGTON AVENUE
- **STREET 2:** 21ST FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02199
- **BUSINESS PHONE:** 18006372929

**MAIL ADDRESS:**
- **STREET 1:** 111 HUNTINGTON AVENUE
- **STREET 2:** 21ST FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02199

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MFS GOVERNMENT MORTGAGE FUND
- **DATE OF NAME CHANGE:** 19930408

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MFS GOVERNMENT INCOME PLUS FUND
- **DATE OF NAME CHANGE:** 19930312

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MASSACHUSETTS MFS GOVERNMENT INCOME PLUS FUND
- **DATE OF NAME CHANGE:** 19921015

## Series and Classes Contracts Data

### MFS Aggressive Growth Allocation Fund (Series ID: S000002506)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000006838 | A            | MAAGX           |
| C000006839 | R4           | MAALX           |
| C000006843 | B            | MBAGX           |
| C000006844 | C            | MCAGX           |
| C000006845 | I            | MIAGX           |
| C000006847 | R1           | MAAFX           |
| C000006849 | R2           | MAWAX           |
| C000006850 | R3           | MAAHX           |
| C000231058 | R6           | AGGPX           |

## Form NPORT-P: Monthly Portfolio Investments Report

### NPORT-P: Part A: General Information

**Item A.1. Information about the Registrant.**

- **a. Name of Registrant:** MFS SERIES TRUST X

- **b. Investment Company Act file number:** 811-04492

- **c. CIK number of Registrant:** 0000783740

- **d. LEI of Registrant:** 5493001MUVNRNUPJY164

- **e. Address and telephone number of Registrant.**

  - **Street Address 1:** 111 HUNTINGTON AVENUE

  - **City:** BOSTON

  - **State:** MA

  - **Foreign country:** US

  - **Zip / Postal Code:** 02199

  - **Telephone number:** 617-954-5000

**Item A.2. Information about the Series.**

- **a. Name of Series:** MFS Aggressive Growth Allocation Fund

- **b. EDGAR series identifier (if any):** S000002506

- **c. LEI of Series:** 549300UEFZYWREX0YF53

**Item A.3. Reporting period.**

- **a. Date of fiscal year-end:** 2026-05-31

- **b. Date as of which information is reported:** 2025-11-30

**Item A.4. Final filing**

Does the Fund anticipate that this will be its final filing on Form N-PORT? **No**

### Fund Information

**Total Assets:** $2984046383.43

**Total Liabilities:** $1456933.15

**Net Assets:** $2982589450.28

**Monthly Return Information**

| Class               | Month 1 Return (%)   | Month 2 Return (%)   | Month 3 Return (%)   |
|:---|:---|:---|:---|
| Class ID C000006838 | 1.45%                | 0.06%                | 0.83%                |
| Class ID C000006839 | 1.44%                | 0.09%                | 0.86%                |
| Class ID C000006843 | 1.35%                | 0.00%                | 0.79%                |
| Class ID C000006844 | 1.35%                | 0.00%                | 0.77%                |
| Class ID C000006845 | 1.44%                | 0.09%                | 0.84%                |
| Class ID C000006847 | 1.37%                | 0.00%                | 0.75%                |
| Class ID C000006849 | 1.39%                | 0.06%                | 0.79%                |
| Class ID C000006850 | 1.43%                | 0.06%                | 0.84%                |
| Class ID C000231058 | 1.47%                | 0.09%                | 0.84%                |

**Monthly Gains & Losses**

| Period   | Net Realized Gain/Loss   | Net Unrealized Appreciation/Depreciation   |
|:---|:---|:---|
| Month 1  | $2120391.10              | $39600114.85                               |
| Month 2  | $3126597.59              | $-476306.09                                |
| Month 3  | $4047412.93              | $20938360.98                               |

### Schedule of Portfolio Investments

| Name                                     | Title                                    | Identifiers                                   | Payoff Profile   | Asset Category   | Issuer Category   | Country   |   Balance | Units   | Value (USD)   | % of Net Assets   | Maturity Date   | Coupon Type   | Annualized Rate (%)   | Restricted?   |   Fair Value Level | Lending Status   |
|:---|:---|:---|:---|:---|:---|:---|---:|:---|:---|:---|:---|:---|:---|:---|---:|:---|
| MFS New Discovery Fund                   | MFS New Discovery Fund                   | CUSIP: 55273H346<br>LEI: ZVEMRLDGMDO1D1VDSU87 | Long             | EC               | RF                | US        |   2161901 | NS      | $76639390.56  | 2.57%             |  |  |  | No            |                  1 | On Loan: No      |
| MFS Value Fund                           | MFS Value Fund                           | CUSIP: 55273H353<br>LEI: HV6C0RMURVKFUQ3UTB42 | Long             | EC               | RF                | US        |   6740674 | NS      | $359143107.74 | 12.04%            |  |  |  | No            |                  1 | On Loan: No      |
| MFS Research International Fund          | MFS Research International Fund          | CUSIP: 55273H361<br>LEI: UH91KW1VFNZQF5FY7237 | Long             | EC               | RF                | US        |   9127119 | NS      | $243785347.56 | 8.17%             |  |  |  | No            |                  1 | On Loan: No      |
| MFS Mid Cap Value Fund                   | MFS Mid Cap Value Fund                   | CUSIP: 55273W475<br>LEI: BXHSCSBXYY1DOHP6E209 | Long             | EC               | RF                | US        |   8906636 | NS      | $300866171.51 | 10.09%            |  |  |  | No            |                  1 | On Loan: No      |
| MFS International Large Cap Value Fund   | MFS International Large Cap Value Fund   | CUSIP: 552743445<br>LEI: 549300YEW2NKJCMQAR75 | Long             | EC               | RF                | US        |   8706450 | NS      | $153668837.12 | 5.15%             |  |  |  | No            |                  1 | On Loan: No      |
| MFS Emerging Markets Equity Fund         | MFS Emerging Markets Equity Fund         | CUSIP: 552746331<br>LEI: GLINMRWNKCBOHYKQ2131 | Long             | EC               | RF                | US        |   1979475 | NS      | $90244277.38  | 3.03%             |  |  |  | No            |                  1 | On Loan: No      |
| MFS International Intrinsic Value Fund   | MFS International Intrinsic Value Fund   | CUSIP: 552746349<br>LEI: 7540QFSKYNTDFH7HAK24 | Long             | EC               | RF                | US        |   3280287 | NS      | $153976682.39 | 5.16%             |  |  |  | No            |                  1 | On Loan: No      |
| MFS International Growth Fund            | MFS International Growth Fund            | CUSIP: 552746356<br>LEI: PTNAY8DC4VJYOKVJ5B83 | Long             | EC               | RF                | US        |   3030647 | NS      | $150835304.18 | 5.06%             |  |  |  | No            |                  1 | On Loan: No      |
| MFS Commodity Strategy Fund              | MFS Commodity Strategy Fund              | CUSIP: 55276T826<br>LEI: T0OEQ8I3F6DXUJCOV412 | Long             | EC               | RF                | US        |  35955489 | NS      | $149574833.99 | 5.01%             |  |  |  | No            |                  1 | On Loan: No      |
| MFS Institutional Money Market Portfolio | MFS Institutional Money Market Portfolio | CUSIP: 55291X109<br>LEI: 5L2W638H85N8T1136O07 | Long             | EC               | RF                | US        |  29756916 | NS      | $29762866.88  | 1.00%             |  |  |  | No            |                  1 | On Loan: No      |
| MFS International New Discovery Fund     | MFS International New Discovery Fund     | CUSIP: 552981383<br>LEI: RC53GXLQZ5LVIZBRHR66 | Long             | EC               | RF                | US        |   3468453 | NS      | $120285949.35 | 4.03%             |  |  |  | No            |                  1 | On Loan: No      |
| MFS Research Fund                        | MFS Research Fund                        | CUSIP: 552981391<br>LEI: XFPOOG2XVG5TW1LZ8588 | Long             | EC               | RF                | US        |   4726657 | NS      | $308225315.69 | 10.33%            |  |  |  | No            |                  1 | On Loan: No      |
| MFS New Discovery Value Fund             | MFS New Discovery Value Fund             | CUSIP: 552982696<br>LEI: LRMRW30Z8FYTIFW1W860 | Long             | EC               | RF                | US        |   4135402 | NS      | $75016189.25  | 2.52%             |  |  |  | No            |                  1 | On Loan: No      |
| MFS Global Real Estate Fund              | MFS Global Real Estate Fund              | CUSIP: 552982720<br>LEI: ROYDM6SL56ZXYAENS860 | Long             | EC               | RF                | US        |   8723323 | NS      | $146726293.84 | 4.92%             |  |  |  | No            |                  1 | On Loan: No      |
| MFS Growth Fund                          | MFS Growth Fund                          | CUSIP: 552985673<br>LEI: K4ZYIH3WSXKUSPKIPM59 | Long             | EC               | RF                | US        |   1477699 | NS      | $334669300.32 | 11.22%            |  |  |  | No            |                  1 | On Loan: No      |
| MFS Mid Cap Growth Fund                  | MFS Mid Cap Growth Fund                  | CUSIP: 552987554<br>LEI: XPX0WXKIO6CLKBLYF666 | Long             | EC               | RF                | US        |   8709978 | NS      | $288909968.70 | 9.69%             |  |  |  | No            |                  1 | On Loan: No      |

### Signature

**Date Signed:** 2025-12-29

**Name of Applicant:** MFS SERIES TRUST X

**Signature:** James Byrne

**Name of Signer:** James Byrne

**Title:** Assistant Treasurer