Tax withholding trims Community Financial (NYSE: CBU) EVP share stake

Rhea-AI Filing Summary

Community Financial System, Inc. executive Maureen A. Gillan-Myer had 522 shares of common stock withheld at $60.55 per share to pay taxes tied to vesting restricted stock awards. After this tax-withholding disposition, she directly holds 5,028 shares and indirectly holds 175.835 shares through the company’s 401(k) plan.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider Gillan-Myer Maureen A

Role EVP, Chief Admin & HR Officer

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	522	$60.55	$32K
holding	Common Stock	--	--	--

Holdings After Transaction: Common Stock — 5,028 shares (Direct); Common Stock — 175.835 shares (Indirect, By 401(k) Plan)

Footnotes (1)

1. Payment of tax liability associated with vesting of restricted stock awards. The number of shares reported herein acquired pursuant to Community Financial System, Inc.'s 401(k) Plan and are based on a current plan statement.

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^*

Gillan-Myer Maureen A

(Last) (First) (Middle)

C/O COMMUNITY FINANCIAL SYSTEM, INC.

333 BUTTERNUT DRIVE

(Street)

SYRACUSE NY 13214

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
COMMUNITY FINANCIAL SYSTEM, INC. [ CBU ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	EVP, Chief Admin & HR Officer

3. Date of Earliest Transaction (Month/Day/Year)
03/02/2026

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	03/02/2026		F(1)		522	D	$60.55	5,028	D
Common Stock								175.835	I	By 401(k) Plan(2)

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. Payment of tax liability associated with vesting of restricted stock awards.

2. The number of shares reported herein acquired pursuant to Community Financial System, Inc.'s 401(k) Plan and are based on a current plan statement.

	/s/ Danielle M. Cima, pursuant to a Confirming Statement executed by Maureen Gillan-Myer	03/04/2026
	** 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 CBU executive Maureen Gillan-Myer report?

Maureen Gillan-Myer reported a tax-withholding disposition of 522 shares of Community Financial System, Inc. common stock. These shares were used to cover taxes from vesting restricted stock awards, rather than an open-market sale of her holdings.

At what price were the CBU shares withheld for Maureen Gillan-Myer?

The 522 Community Financial System, Inc. shares were withheld at $60.55 per share. This price is used solely for calculating the value of shares applied to her tax liability from vesting restricted stock awards on the transaction date.

How many CBU shares does Maureen Gillan-Myer own after the transaction?

After the tax-withholding disposition, Maureen Gillan-Myer directly owns 5,028 shares of Community Financial System, Inc. common stock. She also indirectly owns 175.835 additional shares through the company’s 401(k) Plan, based on a current plan statement.

Was Maureen Gillan-Myer’s CBU transaction an open-market sale?

No, the transaction was not an open-market sale. The 522 Community Financial System, Inc. shares were withheld to pay tax liabilities associated with vesting restricted stock awards, a common administrative mechanism instead of selling shares on the open market.

How are Maureen Gillan-Myer’s indirect CBU holdings structured?

Her indirect holdings consist of 175.835 shares of Community Financial System, Inc. common stock. These shares are held through the company’s 401(k) Plan, with the reported amount based on a current plan statement rather than a new purchase or sale.

What role does Maureen Gillan-Myer hold at Community Financial System, Inc.?

Maureen Gillan-Myer serves as Executive Vice President, Chief Administration and Human Resources Officer at Community Financial System, Inc. Her position makes her a reporting person for insider transactions involving the company’s common stock.