[Form 4] COMMUNITY FINANCIAL SYSTEM, INC. Insider Trading Activity

Rhea-AI Filing Summary

Michele Sullivan, a director of Community Financial System, Inc. (CBU), reported a grant of 416.318 units of deferred (phantom) stock under the company's Deferred Compensation Plan on 09/18/2025. Each unit equals one share of common stock and will be settled in Community Financial System, Inc. common stock at future dates chosen by the reporting person. The reported per-unit value for the award was $59.75. After this transaction Sullivan beneficially owned 2,620.6326 shares (direct). The Form 4 was signed by Danielle M. Cima on 09/22/2025 confirming the transaction.

Positive

• Director participation in Deferred Compensation Plan evidenced by grant of phantom stock units
• Clear disclosure of unit economics: each phantom unit equals one share and settlement will be in common stock

Negative

• None.

Insights

Corporate Governance Expert

TL;DR: Routine deferred compensation award to a director recorded as phantom stock; confirms director participation in company plan.

This Form 4 discloses a non-cash, deferred compensation allocation to a director in the form of phantom stock units, each economically equivalent to one share and payable in common stock at future election dates. Such awards are commonly used to align director interests with shareholders without immediate cash payout. The filing is routine, contains clear settlement mechanics, and specifies post-transaction direct beneficial ownership of 2,620.6326 shares.

Securities/Compensation Analyst

TL;DR: Disclosure shows a 416.318-unit phantom stock grant valued at $59.75 per unit; routine, non-derivative reporting.

The report captures a single non-derivative transaction under the Deferred Compensation Plan dated 09/18/2025. The form clarifies that phantom units are economically equivalent to shares and will be settled in common stock on dates selected by the recipient. Transaction details are complete for SEC Form 4 purposes and the filing was executed by an authorized confirming signer on 09/22/2025.

09/22/2025 - 11:36 AM

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
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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^*

Sullivan Michele

(Last) (First) (Middle)

C/O COMMUNITY FINANCIAL SYSTEM, INC.

5790 WIDEWATERS PARKWAY

(Street)

DEWITT 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)

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

3. Date of Earliest Transaction (Month/Day/Year)
09/18/2025

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

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
Deferred Stock (Deferred Compensation)	(1)	09/18/2025		A		416.318		(1)	(1)	Common Stock	416.318	$59.75	2,620.6326	D

Explanation of Responses:

1. Each unit of phantom stock is the economic equivalent of one share of Community Financial System, Inc. common stock. The units of phantom stock relating to the Deferred Compensation Plan will be settled in Community Financial System, Inc. common stock at future dates selected by the reporting person.

	/s/ Danielle M. Cima, pursuant to Confirming Statement executed by Michele Sullivan	09/22/2025
	** 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 did Michele Sullivan report on Form 4 for CBU?

The report discloses a grant of 416.318 phantom stock units under the Deferred Compensation Plan, each unit equal to one share, dated 09/18/2025.

How many shares does Michele Sullivan beneficially own after the transaction (CBU)?

Following the reported transaction Sullivan beneficially owned 2,620.6326 shares (direct ownership).

At what value were the phantom stock units reported?

The phantom stock units were reported with a per-unit value of $59.75.

How will the phantom stock units be settled?

The filing states the units are the economic equivalent of common stock and will be settled in Community Financial System, Inc. common stock at future dates selected by the reporting person.

Who signed the Form 4 and when was it executed?

The Form 4 was signed by /s/ Danielle M. Cima pursuant to a confirming statement executed by Michele Sullivan on 09/22/2025.