COMMUNITY FINANCIAL SYSTEM, INC. — Director's Dealing 2017

Sep 26, 2017

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: COMMUNITY BANK SYSTEM, INC. (CBU)
CIK: 0000723188
Period of Report: 2017-09-26

Reporting Person: ACE BRIAN R (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2017-09-26	Common Stock	M	5457	$18.09	Acquired	55647	Direct
2017-09-26	Common Stock	S	5457	$53.345	Disposed	50190	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2017-09-26	Stock Option	$18.09	M	5457	Disposed	2018-01-16	Common Stock (5457)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	134	Indirect

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Phantom Stock (Deferred Compensation)	$		Common Stock (20677.0312)	20677.0312	Direct

Footnotes

F1: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $53.20 to $53.49, inclusive. The reporting person undertakes to provide Community Bank System, Inc., any security holder of Community Bank 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.

F2: Each unit of phantom stock is the economic equivalent of one share of Community Bank System, Inc. common stock. The units of phantom stock relating to the Deferred Compensation Plan will be settled in Community Bank System, Inc. common stock at future dates selected by the reporting person.

F3: Includes 137.274 and 131.1844 units of phantom stock acquired on April 10, 2017 and July 10, 2017, respectively, under the Deferred Compensation Plan's dividend reinvestment feature.