NB Bancorp (NBBK) director reports 5,524 restricted shares and 105,761 owned

Rhea-AI Filing Summary

NB Bancorp, Inc. reported that a director acquired 5,524 shares of restricted common stock on January 2, 2026 at a stated price of $0 per share. These restricted shares vest 100% on January 2, 2027, meaning they become fully owned at that time if conditions are met. After this grant, the director beneficially owns 105,761 shares of NB Bancorp stock in total, including other restricted shares that vest at a rate of 20% per year starting on April 24, 2026. The filing is made as a single-reporting-person Form 4 for a board member.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Elliott Mary Susan

Role Director

Type	Security	Shares	Price	Value
Grant/Award	Common Stock	5,524	$0.00	--

Holdings After Transaction: Common Stock — 105,761 shares (Direct)

Footnotes (1)

1. Shares of restricted stock vest 100% on January 2, 2027. Includes shares of restricted stock which vest at a rate of 20% per year commencing on April 24, 2026.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Elliott Mary Susan

(Last) (First) (Middle)

1063 GREAT PLAIN AVE

(Street)

NEEDHAM MA 02492

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
NB Bancorp, Inc. [ NBBK ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
01/02/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	01/02/2026		A		5,524(1)	A	$0	105,761(2)	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Shares of restricted stock vest 100% on January 2, 2027.

2. Includes shares of restricted stock which vest at a rate of 20% per year commencing on April 24, 2026.

	/s/ Steven Lanter, pursuant to power of attorney	01/06/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transaction did NB Bancorp (NBBK) disclose in this filing?

The filing shows a director acquired 5,524 shares of NB Bancorp restricted common stock on January 2, 2026 at a stated price of $0 per share.

How many NB Bancorp (NBBK) shares does the director own after this transaction?

Following the reported transaction, the director beneficially owns 105,761 NB Bancorp shares in total, including restricted stock.

When do the newly granted NB Bancorp restricted shares vest?

The newly granted 5,524 restricted shares vest 100% on January 2, 2027, at which point they become fully owned if conditions are met.

Are there other restricted NB Bancorp (NBBK) shares with different vesting terms?

Yes. The total includes restricted shares that vest at a rate of 20% per year, commencing on April 24, 2026.

What is the reporting person’s relationship to NB Bancorp (NBBK)?

The reporting person is identified as a Director of NB Bancorp, Inc., filing individually as a single reporting person.

Does this NB Bancorp insider filing involve derivative securities?

No derivative securities are reported. The tables show only non-derivative common stock and restricted stock holdings in this filing.