UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14A – 101)

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

Filed by the Registrant  ☒                             Filed by a Party other than the Registrant  ☐

Check the appropriate box:

☐	Preliminary Proxy Statement
☐	Definitive Proxy Statement
☐	Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))
☒	Definitive Additional Materials
☐	Soliciting Material Pursuant to §240.14a-12

ONE Gas, Inc.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

☒	No fee required.
☐	Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.
	(1)	Title of each class of securities to which transaction applies:
	(2)	Aggregate number of securities to which transaction applies:
	(3)	Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (set forth the amount on which the filing fee is calculated and state how it was determined):
	(4)	Proposed maximum aggregate value of transaction:
	(5)	Total fee paid:
☐	Fee paid previously with preliminary materials.
☐	Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.
	(1)	Amount Previously Paid:
	(2)	Form, Schedule or Registration Statement No.:
	(3)	Filing Party:
	(4)	Date Filed:

15 East Fifth Street

Tulsa, OK 74103

918-947-7000 • onegas.com

May 4, 2020

Dear Fellow Shareholder:

We have previously mailed you proxy materials for the ONE Gas, Inc. Annual Meeting of Shareholders to be held on May 21, 2020.

According to our latest records we have not yet received your vote. The Annual Meeting is now only a short time away and your vote is important. Please vote your shares via the internet or by telephone following the instructions on the enclosed Voting Instruction Form or sign and return your Voting Instruction Form today in order to make sure that your shares will be voted at the meeting in accordance with your desires.

If you hold your shares in the name of a brokerage firm, your broker cannot vote your shares on several of the proposals unless your broker receives your specific instructions.

Your board of directors recommends that you vote:

(1) FOR the election of eight director nominees named in the proxy statement to serve on our board for a one-year term;

(2) FOR the ratification of the selection of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the year ending December 31, 2020; and

(3) FOR the advisory proposal to approve our executive compensation.

In the event that your proxy materials have been misplaced, we are enclosing for your use a duplicate Voting Instruction Form and return envelope.

Please follow the telephone or internet voting instructions on your Voting Form or sign and date the enclosed Voting Instruction Form and vote your shares today. In the event that two voting forms are received from you, the one bearing the latest date will be counted, as it automatically revokes all prior votes.

We are actively monitoring the public health and travel concerns relating to the coronavirus (COVID-19) and the protocols that federal, state, and local governments may impose. In the event it is not possible or advisable to hold the annual meeting of shareholders in person, we will announce alternative arrangements for the meeting, which may include a change in venue or holding the meeting solely by means of remote communication. Please monitor the Company’s website at www.onegas.com under the Investors tab for updated information. If you are planning to attend the meeting, please check the website one week prior to the meeting date.

Thank you for voting and for your continued support.

Sincerely,

John W. Gibson,

Chairman of the Board