CBU

SEC source: 0001127602-25-009718 · form4.xml · derivative · entry 3

STICKELS ERIC · CIK 0001201821 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,913.7399

Underlying: Common Stock · 451 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_price: The reporting person has received deferred stock units under the Community Financial System, Inc. 2022 Long-Term Incentive Plan, as amended (the "Plan"). Each phantom stock unit which represents a deferred stock unit is the economic equivalent of one share of Community Financial System, Inc. common stock and will be settled in common stock at a predetermined date.

F2 · derivative.exercise_date: The reporting person has received deferred stock units under the Community Financial System, Inc. 2022 Long-Term Incentive Plan, as amended (the "Plan"). Each phantom stock unit which represents a deferred stock unit is the economic equivalent of one share of Community Financial System, Inc. common stock and will be settled in common stock at a predetermined date.

F2 · derivative.expiration_date: The reporting person has received deferred stock units under the Community Financial System, Inc. 2022 Long-Term Incentive Plan, as amended (the "Plan"). Each phantom stock unit which represents a deferred stock unit is the economic equivalent of one share of Community Financial System, Inc. common stock and will be settled in common stock at a predetermined date.

F3 · balance_after: Includes 102.5299 units of phantom stock acquired as dividend equivalents under the Plan.

SEC source: 0001127602-25-009718 · form4.xml · nonDerivative · entry 1

STICKELS ERIC · CIK 0001201821 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 35,339

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: On March 17, 2025, the reporting person's phantom stock units were settled for 451 shares of Community Financial System, Inc. common stock, and .3719 shares were settled in cash at the price of $57.23 per share

SEC source: 0001127602-25-009370 · form4.xml · nonDerivative · entry 1

Gillan-Myer Maureen A · CIK 0001670754 · EVP, Chief Admin & HR Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,317

F1 · kind: Payment of tax liability associated with vesting of performance stock award.

SEC source: 0001127602-25-009380 · form4.xml · nonDerivative · entry 1

LEVY JEFFREY M · CIK 0001384972 · SVP & Chief Banking Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 6,683.6389

F1 · kind: Payment of tax liability associated with vesting of performance stock award.

SEC source: 0001127602-25-009323 · form4.xml · nonDerivative · entry 1

SUTARIS JOSEPH E · CIK 0001278835 · EVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 14,350.9958

F1 · kind: Payment of tax liability associated with vesting of performance stock award.

SEC source: 0001127602-25-009322 · form4.xml · nonDerivative · entry 1

Karaivanov Dimitar · CIK 0001866135 · Director · President & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 19,230

F1 · kind: Payment of tax liability associated with vesting of performance stock award.

SEC source: 0001127602-25-009008 · form4.xml · nonDerivative · entry 1

LEVY JEFFREY M · CIK 0001384972 · SVP & Chief Banking Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 7,069.2864

F1 · shares: On March 7, 2025, the Compensation Committee approved the vesting of the three-year performance-based restricted stock award, granted to the reporting person in 2022, based on achievement of predetermined performance criteria at the target level. The reporting person received 966 shares of common stock under the award and 101.6475 shares of common stock acquired under the dividend reinvestment feature of the Community Financial System, Inc. 2022 Long-Term Incentive Plan, as amended (the "Plan").

SEC source: 0001127602-25-009004 · form4.xml · nonDerivative · entry 1

Gillan-Myer Maureen A · CIK 0001670754 · EVP, Chief Admin & HR Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,849.1799

F1 · shares: On March 7, 2025, the Compensation Committee approved the vesting of the three-year performance-based restricted stock award, granted to the reporting person in 2022, based on achievement of predetermined performance criteria at the target level. The reporting person received 1,332 shares of common stock under the award and 140.1799 shares of common stock acquired under the dividend reinvestment feature of the Community Financial System, Inc. 2022 Long-Term Incentive Plan, as amended (the "Plan").

SEC source: 0001127602-25-009003 · form4.xml · nonDerivative · entry 1

SUTARIS JOSEPH E · CIK 0001278835 · EVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 15,044.0245

F1 · shares: On March 7, 2025, the Compensation Committee approved the vesting of the three-year performance-based restricted stock award, granted to the reporting person in 2022, based on achievement of predetermined performance criteria at the target level. The reporting person received 1,739 shares of common stock under the award and 183.0287 shares of common stock acquired under the dividend reinvestment feature of the Community Financial System, Inc. 2022 Long-Term Incentive Plan, as amended (the "Plan").

SEC source: 0001127602-25-008970 · form4.xml · nonDerivative · entry 1

Karaivanov Dimitar · CIK 0001866135 · Director · President & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 21,063.9843

F1 · shares: On March 7, 2025, the Compensation Committee approved the vesting of the three-year performance-based restricted stock award, granted to the reporting person in 2022, based on achievement of predetermined performance criteria at the target level. The reporting person received 3,069 shares of common stock under the award and 322.9843 shares of common stock acquired under the dividend reinvestment feature of the Community Financial System, Inc. 2022 Long-Term Incentive Plan, as amended (the "Plan").

SEC source: 0001127602-25-007695 · form4.xml · nonDerivative · entry 1

LEVY JEFFREY M · CIK 0001384972 · SVP & Chief Banking Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 6,001.6389

F1 · kind: Payment of tax liability associated with vesting of restricted stock award.

SEC source: 0001127602-25-007692 · form4.xml · nonDerivative · entry 1

SUTARIS JOSEPH E · CIK 0001278835 · EVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 13,121.9958

F1 · kind: Payment of tax liability associated with the vesting of restricted stock awards.

SEC source: 0001127602-25-007691 · form4.xml · nonDerivative · entry 1

Karaivanov Dimitar · CIK 0001866135 · Director · President & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 17,672

F1 · kind: Payment of tax liability associated with vesting of restricted stock award.

SEC source: 0001127602-25-007690 · form4.xml · nonDerivative · entry 1

Durkee Deresa Fischer · CIK 0001608689 · SVP, Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,654.604

F1 · kind: Payment of tax liability associated with vesting of restricted stock award.

SEC source: 0001127602-25-007689 · form4.xml · nonDerivative · entry 1

Gillan-Myer Maureen A · CIK 0001670754 · EVP, Chief Admin & HR Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 3,377

F1 · kind: Payment of tax liability associated with vesting of restricted stock awards.

SEC source: 0001127602-25-007688 · form4.xml · nonDerivative · entry 1

Abdo Michael N · CIK 0001933852 · EVP and General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,404

F1 · kind: Payment of tax liability associated with vesting of restricted stock awards.

SEC source: 0001127602-25-002076 · form4.xml · nonDerivative · entry 1

LEVY JEFFREY M · CIK 0001384972 · SVP & Chief Banking Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 6,538.6389

SEC source: 0001127602-25-001422 · form4.xml · derivative · entry 7

Bolus Mark J. · CIK 0001486056 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,672.7862

Underlying: Common Stock · 712 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F5 · derivative.exercise_price: The reporting person has received deferred stock units under the Community Financial System, Inc. 2022 Long-Term Incentive Plan, as amended (the "Plan"). Each phantom stock unit which represents a deferred stock unit is the economic equivalent of one share of Community Financial System, Inc. common stock and will be settled in common stock at a predetermined date.

F5 · derivative.exercise_date: The reporting person has received deferred stock units under the Community Financial System, Inc. 2022 Long-Term Incentive Plan, as amended (the "Plan"). Each phantom stock unit which represents a deferred stock unit is the economic equivalent of one share of Community Financial System, Inc. common stock and will be settled in common stock at a predetermined date.

F5 · derivative.expiration_date: The reporting person has received deferred stock units under the Community Financial System, Inc. 2022 Long-Term Incentive Plan, as amended (the "Plan"). Each phantom stock unit which represents a deferred stock unit is the economic equivalent of one share of Community Financial System, Inc. common stock and will be settled in common stock at a predetermined date.

F6 · balance_after: Includes 103.1993 units of phantom stock acquired as dividend equivalents under the Plan.

SEC source: 0001127602-25-001422 · form4.xml · nonDerivative · entry 1

Bolus Mark J. · CIK 0001486056 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 101,769.069

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: On January 15, 2025, the reporting person's deferred stock units were settled for 712 shares of Community Financial System, Inc. common stock, and .0872 shares were settled in cash at the price of $61.60 per share.

F2 · balance_after: Includes 2,129.519 shares acquired pursuant to the Community Financial System, Inc. Dividend Reinvestment Plan.

SEC source: 0001127602-25-001205 · form4.xml · derivative · entry 3

STEELE SALLY A · CIK 0001264816 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 28 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_price: 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.

F2 · derivative.exercise_date: 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.

F2 · derivative.expiration_date: 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.

F3 · derivative.underlying_shares: Includes 28.7195 units of phantom stock acquired on January 10, 2025 under the Deferred Compensation Plan's dividend reinvestment feature.

SEC source: 0001127602-25-001205 · form4.xml · nonDerivative · entry 1

STEELE SALLY A · CIK 0001264816 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 38,783

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: On January 13, 2025, the reporting person's phantom stock units were settled for 28 shares of Community Financial System, Inc. common stock, and .7195 shares were settled in cash at the price of $58.68 per share.

SEC source: 0001127602-25-000675 · form4.xml · derivative · entry 3

STEELE SALLY A · CIK 0001264816 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 3,663 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_price: 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.

F2 · derivative.exercise_date: 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.

F2 · derivative.expiration_date: 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.

F3 · derivative.underlying_shares: Includes 165.9356 units of phantom stock acquired under the Deferred Compensation Plan's dividend reinvestment feature.

SEC source: 0001127602-25-000675 · form4.xml · nonDerivative · entry 1

STEELE SALLY A · CIK 0001264816 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 38,755

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: On January 2, 2025, the reporting person's phantom stock units were settled for 3,663 shares of Community Financial System, Inc. common stock, and .5912 shares were settled in cash at the price of $61.68 per share.

SEC source: 0001127602-24-029841 · form4.xml · derivative · entry 1

Pecor Raymond C III · CIK 0001475265 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,451.9553

Underlying: Common Stock · 375.6329 shares

Expires not disclosed

F1 · derivative.exercise_price: 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.

F1 · derivative.exercise_date: 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.

F1 · derivative.expiration_date: 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.

F2 · balance_after: Includes 67.8293, 66.08, and 60.6914 units of phantom stock acquired on April 10, 2024, July 10, 2024, and October 10, 2024, respectively, under the dividend reinvestment feature.

SEC source: 0001127602-24-029837 · form4.xml · derivative · entry 1

Sullivan Michele · CIK 0002009605 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,362.0292

Underlying: Common Stock · 326.6373 shares

Expires not disclosed

F1 · derivative.exercise_price: 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.

F1 · derivative.exercise_date: 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.

F1 · derivative.expiration_date: 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.

F2 · balance_after: Includes 2.5397 and 5.4648 units of phantom stock acquired on July 10, 2024 and October 10, 2024, respectively, under the dividend reinvestment feature.

SEC source: 0001127602-24-028354 · form4.xml · derivative · entry 2

Whipple John F. · CIK 0001485739 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 6,848.6393

Underlying: Common Stock · 1,313 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_price: 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 (the "Plan") will be settled in Community Financial System, Inc. common stock at future dates selected by the reporting person.

F1 · price: On December 2, 2024, the reporting person's phantom stock units were settled for 1,313 shares of Community Financial System, Inc. common stock and a cash payment in lieu of .2529 shares of common stock.

F2 · derivative.exercise_date: 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 (the "Plan") will be settled in Community Financial System, Inc. common stock at future dates selected by the reporting person.

F2 · derivative.expiration_date: 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 (the "Plan") will be settled in Community Financial System, Inc. common stock at future dates selected by the reporting person.

F3 · balance_after: Includes 70.4764, 82.1037, 74.9451 and 64.499 units of phantom stock acquired on January 10, 2024, April 10, 2024, July 10, 2024, and October 10, 2024, respectively, as dividend equivalents under the Plan.

SEC source: 0001127602-24-028354 · form4.xml · nonDerivative · entry 1

Whipple John F. · CIK 0001485739 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 7,136.0302

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: On December 2, 2024, the reporting person's phantom stock units were settled for 1,313 shares of Community Financial System, Inc. common stock and a cash payment in lieu of .2529 shares of common stock.

SEC source: 0001127602-24-028166 · form4.xml · derivative · entry 4

Abdo Michael N · CIK 0001933852 · EVP and General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 2,100 shares

Expires 2025-03-18

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: The option vested ratably on March 18, 2016, 2017, 2018, 2019, and 2020.

SEC source: 0001127602-24-028166 · form4.xml · nonDerivative · entry 2

Abdo Michael N · CIK 0001933852 · EVP and General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,836

SEC source: 0001127602-24-028166 · form4.xml · nonDerivative · entry 1

Abdo Michael N · CIK 0001933852 · EVP and General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 7,258

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-24-028163 · form4.xml · derivative · entry 10

SUTARIS JOSEPH E · CIK 0001278835 · EVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,382

Underlying: Common Stock · 2,524 shares

Expires 2030-03-17

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F5 · derivative.exercise_date: The option vests ratably on March 17, 2021, 2022, 2023, 2024, and 2025.

SEC source: 0001127602-24-028163 · form4.xml · derivative · entry 9

SUTARIS JOSEPH E · CIK 0001278835 · EVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 1,559 shares

Expires 2028-03-20

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F4 · derivative.exercise_date: The option vested ratably on March 20, 2019, 2020, 2021, 2022 and 2023.

SEC source: 0001127602-24-028163 · form4.xml · derivative · entry 8

SUTARIS JOSEPH E · CIK 0001278835 · EVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 1,503 shares

Expires 2027-03-15

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F3 · derivative.exercise_date: The option vested ratably on March 15, 2018, 2019, 2020, 2021 and 2022.

SEC source: 0001127602-24-028163 · form4.xml · derivative · entry 7

SUTARIS JOSEPH E · CIK 0001278835 · EVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 2,061 shares

Expires 2026-03-16

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: The option vested ratably on March 16, 2017, 2018, 2019, 2020 and 2021.

SEC source: 0001127602-24-028163 · form4.xml · nonDerivative · entry 5

SUTARIS JOSEPH E · CIK 0001278835 · EVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 13,919.9958

SEC source: 0001127602-24-028163 · form4.xml · nonDerivative · entry 4

SUTARIS JOSEPH E · CIK 0001278835 · EVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,093.9958

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-24-028163 · form4.xml · nonDerivative · entry 3

SUTARIS JOSEPH E · CIK 0001278835 · EVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 17,569.9958

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-24-028163 · form4.xml · nonDerivative · entry 2

SUTARIS JOSEPH E · CIK 0001278835 · EVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,010.9958

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-24-028163 · form4.xml · nonDerivative · entry 1

SUTARIS JOSEPH E · CIK 0001278835 · EVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 14,507.9958

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-24-028048 · form4.xml · derivative · entry 3

Whipple John F. · CIK 0001485739 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 3,937 shares

Expires 2025-03-18

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-24-028048 · form4.xml · nonDerivative · entry 2

Whipple John F. · CIK 0001485739 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,823.0302

SEC source: 0001127602-24-028048 · form4.xml · nonDerivative · entry 1

Whipple John F. · CIK 0001485739 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,760.0302

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-24-027345 · form4a.xml · derivative · entry 7

Durkee Deresa Fischer · CIK 0001608689 · SVP, Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 427

Underlying: Common Stock · 1,705 shares

Expires 2030-03-17

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · date: Due to an administrative error, the Reporting Person is filing this amendment to correct the date of the transaction to November 7, 2024 and update the price of the Community Financial System, Inc. common stock used for the settlement of shares to cover the exercise price and the taxes associated with this stock option exercise. The number of shares tendered to cover the exercise price and taxes has been reduced from 1,841 shares to 1,711 shares.

F3 · derivative.exercise_date: The option vests ratably on March 17, 2021, 2022, 2023, 2024, and 2025.

SEC source: 0001127602-24-027345 · form4a.xml · derivative · entry 6

Durkee Deresa Fischer · CIK 0001608689 · SVP, Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 427 shares

Expires 2026-03-16

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · date: Due to an administrative error, the Reporting Person is filing this amendment to correct the date of the transaction to November 7, 2024 and update the price of the Community Financial System, Inc. common stock used for the settlement of shares to cover the exercise price and the taxes associated with this stock option exercise. The number of shares tendered to cover the exercise price and taxes has been reduced from 1,841 shares to 1,711 shares.

F2 · derivative.exercise_date: The option vested ratably on March 16, 2017, 2018, 2019, 2020, and 2021.

SEC source: 0001127602-24-027345 · form4a.xml · nonDerivative · entry 3

Durkee Deresa Fischer · CIK 0001608689 · SVP, Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,980.604

F1 · date: Due to an administrative error, the Reporting Person is filing this amendment to correct the date of the transaction to November 7, 2024 and update the price of the Community Financial System, Inc. common stock used for the settlement of shares to cover the exercise price and the taxes associated with this stock option exercise. The number of shares tendered to cover the exercise price and taxes has been reduced from 1,841 shares to 1,711 shares.

SEC source: 0001127602-24-027345 · form4a.xml · nonDerivative · entry 2

Durkee Deresa Fischer · CIK 0001608689 · SVP, Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 6,691.604

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · date: Due to an administrative error, the Reporting Person is filing this amendment to correct the date of the transaction to November 7, 2024 and update the price of the Community Financial System, Inc. common stock used for the settlement of shares to cover the exercise price and the taxes associated with this stock option exercise. The number of shares tendered to cover the exercise price and taxes has been reduced from 1,841 shares to 1,711 shares.

SEC source: 0001127602-24-027345 · form4a.xml · nonDerivative · entry 1

Durkee Deresa Fischer · CIK 0001608689 · SVP, Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,986.604

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · date: Due to an administrative error, the Reporting Person is filing this amendment to correct the date of the transaction to November 7, 2024 and update the price of the Community Financial System, Inc. common stock used for the settlement of shares to cover the exercise price and the taxes associated with this stock option exercise. The number of shares tendered to cover the exercise price and taxes has been reduced from 1,841 shares to 1,711 shares.

SEC source: 0001127602-24-026696 · form4.xml · derivative · entry 6

Bolus Mark J. · CIK 0001486056 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 1,969 shares

Expires 2025-03-18

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-24-026696 · form4.xml · derivative · entry 5

Bolus Mark J. · CIK 0001486056 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 2,123 shares

Expires 2026-03-16

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-24-026696 · form4.xml · nonDerivative · entry 4

Bolus Mark J. · CIK 0001486056 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 98,927.55

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $70.50 to $70.945, inclusive. The reporting person undertakes to provide Community Financial System, Inc., any security holder of Community Financial System, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.