# EDGAR Filing Document

**Accession Number:** 0001943802
**File Stem:** 0001193125-26-289494
**Filing Date:** 2026-6
**Character Count:** 7245
**Document Hash:** a6bb6f2e791954db7633323323f8a028
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-289494.hdr.sgml**: 20260630

**ACCESSION NUMBER**: 0001193125-26-289494

**CONFORMED SUBMISSION TYPE**: NT 11-K

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20251231

**FILED AS OF DATE**: 20260630

**DATE AS OF CHANGE**: 20260630

**EFFECTIVENESS DATE**: 20260630

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** First Seacoast Bancorp, Inc.
- **CENTRAL INDEX KEY:** 0001943802
- **STANDARD INDUSTRIAL CLASSIFICATION:** SAVINGS INSTITUTION, FEDERALLY CHARTERED [6035]
- **ORGANIZATION NAME:** 02 Finance
- **EIN:** 920334805
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** NT 11-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-41597
- **FILM NUMBER:** 261138162

**BUSINESS ADDRESS:**
- **STREET 1:** 633 CENTRAL AVENUE
- **CITY:** DOVER
- **STATE:** NH
- **ZIP:** 03820
- **BUSINESS PHONE:** 603-742-4680

**MAIL ADDRESS:**
- **STREET 1:** 633 CENTRAL AVENUE
- **CITY:** DOVER
- **STATE:** NH
- **ZIP:** 03820

**UNITED STATES** 

**SECURITIES AND EXCHANGE COMMISSION** 

**WASHINGTON, D.C. 20549** 

**FORM 12b-25** 

**Commission File No. 001-41597** 

**NOTIFICATION OF LATE FILING** 

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| | |
|:---|:---|
| *(Check One):* | ☐ Form 10-K ☐ Form 20-F ☒ Form 11-K ☐ Form 10-Q<br> ☐ Form 10-D ☐ Form N-CEN ☐ Form N-CSR |
|  | For Period Ended: December 31, 2025 |
|  | ☐ Transition Report on Form 10-K |
|  | ☐ Transition Report on Form 20-F |
|  | ☐ Transition Report on Form 11-K |
|  | ☐ Transition Report on Form 10-Q |
|  | For the Transition Period Ended:<u> </u> |

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&nbsp;&nbsp;&nbsp; **Nothing in this form shall be construed to imply that the Commission has verified any information contained herein.**<br>

If the notification relates to a portion of the filing checked above, identify the Item(s) to which the notification relates: N/A

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**PART I — REGISTRANT INFORMATION** 

## First Seacoast Bank 401(k) Plan
**Full name of registrant** 

**Former name if applicable** 

**633 Central Avenue** 

**Address of principal executive office (Street and Number)** 

**Dover, New Hampshire 03820** 

**City, state and zip code** 

**PART II – RULES 12b-25(b) AND (c)** 

If the subject report could not be filed without unreasonable effort or expense and the registrant seeks relief pursuant to Rule 12b-25(b), the following should be completed. (Check box if appropriate)

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| | | |
|:---|:---|:---|
| ☒ | (a) | The reasons described in reasonable detail in Part III of this form could not be eliminated without unreasonable effort or expense; |
| ☒ | (b) | The subject annual report, semi-annual report, transition report on Form 10-K, Form 20-F, Form 11-K, Form N-CEN or Form N-CSR, or portion thereof, will be filed on or before the fifteenth calendar day following the prescribed due date; or the subject quarterly report or transition report on Form 10-Q or subject distribution report on Form 10-D, or portion thereof, will be filed on or before the fifth calendar day following the prescribed due date; and |
| ☒ | (c) | The accountant's statement or other exhibit required by Rule 12b-25(c) has been attached if applicable. |

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**PART III — NARRATIVE** 

State below in reasonable detail why Forms 10-K, 20-F, 11-K, 10-Q, 10-D, N-SAR, N-CSR, or the transition report or portion thereof, could not be filed within the prescribed time period.

The Form 11-K which is the subject of this 12b-25 extension is being filed in order to report the information required of the First Seacoast Bank 401(k) Plan (the "Plan"). Although the Plan's Annual Report on Form 11-K for the year ended December 31, 2025 had been fully prepared within the prescribed time period, the Plan was unable to complete the necessary iXBRL tagging and testing without unreasonable effort or expense. In order to ensure the accuracy of the information contained in the Form 11-K, the Plan believes it is necessary to obtain an extension of the filing date. The Registrant plans to file the Form 11-K no later than the fifteenth calendar day following the prescribed due date.

**PART IV — OTHER INFORMATION** 

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| | | | |
|:---|:---|:---|:---|
| (1) | Name and telephone number of person to contact in regard to this notification. | Name and telephone number of person to contact in regard to this notification. | Name and telephone number of person to contact in regard to this notification. |
|  | **James R. Brannen** | **(603)** | **742-4680** |
|  | (Name) | (Area Code) | (Telephone Number) |
| (2) | Have all other periodic reports required under Section 13 or 15(d) of the Securities Exchange Act of 1934 or Section 30 of the Investment Company Act of 1940 during the preceding 12 months or for such shorter period that the registrant was required to file such report(s) been filed? If the answer is no, identify report(s). ☑ Yes ☐ No | Have all other periodic reports required under Section 13 or 15(d) of the Securities Exchange Act of 1934 or Section 30 of the Investment Company Act of 1940 during the preceding 12 months or for such shorter period that the registrant was required to file such report(s) been filed? If the answer is no, identify report(s). ☑ Yes ☐ No | Have all other periodic reports required under Section 13 or 15(d) of the Securities Exchange Act of 1934 or Section 30 of the Investment Company Act of 1940 during the preceding 12 months or for such shorter period that the registrant was required to file such report(s) been filed? If the answer is no, identify report(s). ☑ Yes ☐ No |
| (3) | It is anticipated that any significant change in results of operations from the corresponding period for the last fiscal year will be reflected by the earnings statements to be included in the subject report or portion thereof? ☐ Yes ☑ No | It is anticipated that any significant change in results of operations from the corresponding period for the last fiscal year will be reflected by the earnings statements to be included in the subject report or portion thereof? ☐ Yes ☑ No | It is anticipated that any significant change in results of operations from the corresponding period for the last fiscal year will be reflected by the earnings statements to be included in the subject report or portion thereof? ☐ Yes ☑ No |
|  | If so: attach an explanation of the anticipated change, both narratively and quantitatively, and if appropriate, state the reasons why a reasonable estimate of the results cannot be made. | If so: attach an explanation of the anticipated change, both narratively and quantitatively, and if appropriate, state the reasons why a reasonable estimate of the results cannot be made. | If so: attach an explanation of the anticipated change, both narratively and quantitatively, and if appropriate, state the reasons why a reasonable estimate of the results cannot be made. |

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**First Seacoast Bank 401(k) Plan** 

**(Name of Registrant as Specified in Charter)** 

Has caused this notification to be signed on its behalf by the undersigned thereunto duly authorized.

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| | | |
|:---|:---|:---|
| Date: June 30, 2026 | By: | /s/ James R. Brannen |
|  |  | James R. Brannen<br> Chief Executive Officer |

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