SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

Catalyst Bancorp, Inc.

(Name of Issuer)

Common Stock, par value $0.01 per share

(Title of Class of Securities)

14888L101

(CUSIP Number)

Mr. Joseph Stilwell
200 Calle del Santo Cristo, Segundo Piso
San Juan, PR, 00901
787-985-2193

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

10/23/2025

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. Checkbox not checked

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

CUSIP No.

14888L101

Name of reporting person

Stilwell Activist Fund, L.P.

Check the appropriate box if a member of a Group (See Instructions)

(a)

(b)

SEC use only

Source of funds (See Instructions)

WC, OO

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

Checkbox not checked

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 215,983.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 215,983.00

Aggregate amount beneficially owned by each reporting person

215,983.00

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in Row (11)

5.2 %

Type of Reporting Person (See Instructions)

SCHEDULE 13D

CUSIP No.

14888L101

Name of reporting person

Stilwell Activist Investments, L.P.

Check the appropriate box if a member of a Group (See Instructions)

(a)

(b)

SEC use only

Source of funds (See Instructions)

WC, OO

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

Checkbox not checked

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 215,983.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 215,983.00

Aggregate amount beneficially owned by each reporting person

215,983.00

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in Row (11)

5.2 %

Type of Reporting Person (See Instructions)

SCHEDULE 13D

CUSIP No.

14888L101

Name of reporting person

STILWELL PARTNERS L P

Check the appropriate box if a member of a Group (See Instructions)

(a)

(b)

SEC use only

Source of funds (See Instructions)

WC, OO

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

Checkbox not checked

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 215,983.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 215,983.00

Aggregate amount beneficially owned by each reporting person

215,983.00

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in Row (11)

5.2 %

Type of Reporting Person (See Instructions)

SCHEDULE 13D

CUSIP No.

14888L101

Name of reporting person

Stilwell Value LLC

Check the appropriate box if a member of a Group (See Instructions)

(a)

(b)

SEC use only

Source of funds (See Instructions)

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

Checkbox checked

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 215,983.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 215,983.00

Aggregate amount beneficially owned by each reporting person

215,983.00

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in Row (11)

5.2 %

Type of Reporting Person (See Instructions)

SCHEDULE 13D

CUSIP No.

14888L101

Name of reporting person

STILWELL JOSEPH

Check the appropriate box if a member of a Group (See Instructions)

(a)

(b)

SEC use only

Source of funds (See Instructions)

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

Checkbox not checked

Citizenship or place of organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 215,983.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 215,983.00

Aggregate amount beneficially owned by each reporting person

215,983.00

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in Row (11)

5.2 %

Type of Reporting Person (See Instructions)

SCHEDULE 13D

Item 1.

Security and Issuer

(a)

Title of Class of Securities:

Common Stock, par value $0.01 per share

(b)

Name of Issuer:

Catalyst Bancorp, Inc.

(c)

Address of Issuer's Principal Executive Offices:

235 N. COURT STREET, OPELOUSAS, LOUISIANA , 70570.

Item 2.

Identity and Background

(a)

This Schedule 13D is being filed jointly by Stilwell Activist Fund, L.P., a Delaware limited partnership ("Stilwell Activist Fund"); Stilwell Activist Investments, L.P., a Delaware limited partnership ("Stilwell Activist Investments"); Stilwell Partners, L.P., a Delaware limited partnership ("Stilwell Partners"); Stilwell Value LLC, a Delaware limited liability company ("Stilwell Value LLC") and the general partner of Stilwell Activist Fund, Stilwell Activist Investments, and Stilwell Partners; and Joseph Stilwell, the managing member and owner of Stilwell Value LLC (collectively, "we" or "us"). The filers of this statement are collectively referred to herein as the "Group." The joint filing agreement of the members of the Group is filed as Exhibit 1 to this Schedule 13D. This statement is filed by Joseph Stilwell with respect to the shares of common stock, par value $0.01 per share (the "Common Stock") of Catalyst Bancorp, Inc. (the "Issuer") beneficially owned by Joseph Stilwell, including shares of Common Stock held in the names of Stilwell Activist Fund, Stilwell Activist Investments, and Stilwell Partners, in Joseph Stilwell's capacities as the managing member and owner of Stilwell Value LLC, which is the general partner of Stilwell Activist Fund, Stilwell Activist Investments, and Stilwell Partners.

(b)

The business address of Stilwell Activist Fund, Stilwell Activist Investments, Stilwell Partners, and Stilwell Value LLC is 111 Broadway, 12th Floor, New York, New York 10006. The business address of Joseph Stilwell is 200 Calle del Santo Cristo, Segundo Piso, San Juan, Puerto Rico 00901.

(c)

The principal employment of Joseph Stilwell is investment management. Stilwell Activist Fund, Stilwell Activist Investments, and Stilwell Partners are private investment partnerships engaged in the purchase and sale of securities for their own accounts. Stilwell Value LLC serves as the general partner of Stilwell Activist Fund, Stilwell Activist Investments, Stilwell Partners, and related partnerships.

(d)

During the past five years, no member of the Group has been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors).

(e)

During the past five years, no member of the Group has been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and, as a result of such proceeding, was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, Federal or State securities laws or finding any violation with respect to such laws, except as indicated in Schedule B, attached hereto and incorporated herein by reference.

(f)

Joseph Stilwell is a citizen of the United States.

Item 3.

Source and Amount of Funds or Other Consideration

Stilwell Activist Fund has expended $373,276.51 to acquire 28,839 shares of Common Stock. Such funds were provided from Stilwell Activist Fund's working capital and may, from time to time, be provided in part by margin account loans from subsidiaries of Morgan Stanley or Interactive Brokers extended in the ordinary course of business. Stilwell Activist Investments has expended $1,907,466.52 to acquire 147,153 shares of Common Stock. Such funds were provided from Stilwell Activist Investments' working capital and may, from time to time, be provided in part by margin account loans from subsidiaries of Morgan Stanley, Interactive Brokers or Velocity Clearing LLC extended in the ordinary course of business. Stilwell Partners has expended a total of $517,678.83 to acquire 39,991 shares of Common Stock. Such funds were provided from Stilwell Partners' working capital and may, from time to time, be provided in part by margin account loans from subsidiaries of Morgan Stanley or J.P. Morgan extended in the ordinary course of business. All purchases of shares of Common Stock made by the Group using funds borrowed from subsidiaries of Morgan Stanley, J.P. Morgan, Interactive Brokers or Velocity Clearing LLC, if any, were made in margin transactions on their usual terms and conditions, except as disclosed below in Item 5. All or part of the shares of Common Stock owned by members of the Group may from time to time be pledged with one or more banking institutions or brokerage firms as collateral for loans made by such entities to members of the Group. Such loans generally bear interest at a rate based on the broker's call rate from time to time in effect. Such indebtedness, if any, may be refinanced with other banks or broker-dealers.

Item 4.

Purpose of Transaction

We hope to work with management and the board to maximize shareholder value. Our purpose in acquiring shares of Common Stock of the Issuer is to profit from the appreciation in the market price of the shares of Common Stock through asserting shareholder rights. We do not believe the value of the Issuer's assets is adequately reflected in the current market price of the Issuer's Common Stock. Members of the Group may seek to make additional purchases or sales of shares of Common Stock. Except as described in this filing, no member of the Group has any plans or proposals which relate to, or could result in, any of the matters referred to in paragraphs (a) through (j), inclusive, of Item 4 of Schedule 13D. Members of the Group may, at any time and from time to time, review or reconsider their positions and formulate plans or proposals with respect thereto. Since 2000, members or affiliates of the Group have taken an 'activist position' in 78 other publicly-traded companies. In each instance, our purpose has been to profit from the appreciation in the market price of the shares we held by asserting shareholder rights. In addition, we believed that the values of the companies' assets were not adequately reflected in the market prices of their shares. Our actions with respect to such publicly-traded companies are described in Schedule A, attached hereto and incorporated herein by reference.

Item 5.

Interest in Securities of the Issuer

(a)

The members of the Group beneficially own an aggregate of 215,983 shares of Common Stock. The percentages used in this filing are calculated based on 4,129,604 shares of Common Stock outstanding as of September 30, 2025, as reported in Exhibit 99.1 to the Issuer's Current Report on Form 8-K filed with the Securities and Exchange Commission on October 23, 2025. The purchases and sales of Common Stock reported in this item, if any, were made in open-market transactions. Each of Stilwell Activist Fund, Stilwell Activist Investments, Stilwell Partners, Stilwell Value LLC and Joseph Stilwell may be deemed to beneficially own 215,983 shares of Common Stock, constituting approximately 5.2% of the shares of Common Stock outstanding.

(b)

Each of Stilwell Activist Fund, Stilwell Activist Investments, Stilwell Partners, Stilwell Value LLC and Joseph Stilwell may be deemed to share the power to vote and dispose of 215,983 shares of Common Stock owned in the aggregate by Stilwell Activist Fund, Stilwell Activist Investments, and Stilwell Partners. Because he is the managing member and owner of Stilwell Value LLC, which is the general partner of each of Stilwell Activist Fund, Stilwell Activist Investments, and Stilwell Partners, Joseph Stilwell has the power to direct the affairs of each of Stilwell Activist Fund, Stilwell Activist Investments, and Stilwell Partners, including the voting and disposition of shares of Common Stock held in the name of each of Stilwell Activist Fund, Stilwell Activist Investments, and Stilwell Partners. Therefore, Joseph Stilwell is deemed to share voting and disposition power with each of Stilwell Activist Fund, Stilwell Activist Investments, and Stilwell Partners with regard to those shares of Common Stock. Because he is the managing member and owner of Stilwell Value LLC, Joseph Stilwell has the power to direct the affairs of Stilwell Value LLC. Stilwell Value LLC is the general partner of each of Stilwell Activist Fund, Stilwell Activist Investments, and Stilwell Partners. Therefore, Stilwell Value LLC may be deemed to share with Joseph Stilwell voting and disposition power with regard to the shares of Common Stock held by each of Stilwell Activist Fund, Stilwell Activist Investments, and Stilwell Partners.

(c)

Within the past sixty days, each of Stilwell Activist Fund and Stilwell Activist Investments purchased shares of Common Stock in the open market as set forth in Schedule C, attached hereto and incorporated herein by reference. Within the past sixty days, Stilwell Partners has not purchased or sold any shares of Common Stock. Stilwell Value LLC and Joseph Stilwell have not purchased or sold any shares of Common Stock.

(d)

No person other than Stilwell Activist Fund, Stilwell Activist Investments, Stilwell Partners, Stilwell Value LLC and Joseph Stilwell is known to have the right to receive, or the power to direct the receipt of dividends from, or proceeds from the sale of, the shares of Common Stock.

(e)

Not applicable.

Item 6.

Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer

Other than the Joint Filing Agreement filed as Exhibit 1 to this Schedule 13D, there are no contracts, arrangements, understandings or relationships among the persons named in Item 2 hereof and between such persons and any person with respect to any securities of the Issuer, including but not limited to transfer or voting of any of the securities, finders' fees, joint ventures, loan or option arrangements, puts or calls, guarantees of profits, divisions of profits or losses, or the giving or withholding of proxies, except for sharing of profits. See Items 1 and 2 above regarding disclosure of the relationships between the Group, which disclosure is incorporated herein by reference.

Item 7.

Material to be Filed as Exhibits.

Schedule A - Stilwell Activist History Schedule B - Item 2(e) Schedule C - Transactions in Securities Exhibit 1 - Joint Filing Agreement, dated October 30, 2025.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Stilwell Activist Fund, L.P.

Signature:	/s/ Megan Parisi
Name/Title:	Megan Parisi, Member of Stilwell Value LLC, its General Partner
Date:	10/30/2025

Stilwell Activist Investments, L.P.

Signature:	/s/ Megan Parisi
Name/Title:	Megan Parisi, Member of Stilwell Value LLC, its General Partner
Date:	10/30/2025

STILWELL PARTNERS L P

Signature:	/s/ Megan Parisi
Name/Title:	Megan Parisi, Member of Stilwell Value LLC, its General Partner
Date:	10/30/2025

Stilwell Value LLC

Signature:	/s/ Megan Parisi
Name/Title:	Megan Parisi, Member
Date:	10/30/2025

STILWELL JOSEPH

Signature:	/s/ Joseph Stilwell
Name/Title:	Joseph Stilwell*
Date:	10/30/2025

Megan Parisi

Signature:	/s/ Megan Parisi
Name/Title:	*Megan Parisi, Attorney-in-Fact
Date:	10/30/2025

SEC Form SCHEDULE 13D filed by Catalyst Bancorp Inc.