X0306 4 2018-08-21 0 0001587732 ONE Gas, Inc. OGS 0001629039 Acosta Arcilia 15 EAST 5TH STREET TULSA OK 74103 1 0 0 0 Common stock, par value $0.01 2018-08-21 4 A 0 1012 80.30 A 1012 D Phantom Stock 2018-08-21 4 A 0 1012 80.30 A Common stock, par value $0.01 1012 1012 D Annual cash retainer elected to be received in shares and annual stock retainer shares are issued under the Issuer's Equity Compensation Plan. Reporting person elected 50 percent of her annual cash retainer to be received in shares of ONE Gas common stock. Shares of phantom stock are convertible into ONE Gas' common stock on a 1-for-1 ratio. Annual cash and/or stock retainer elected to be deferred to phantom stock under ONE Gas' Deferred Compensation Plan for Non-Employee Directors. Phantom stock is accrued under ONE Gas' Deferred Compensation Plan for Non-Employee Directors (the "Plan") and is settled in shares of ONE Gas common stock at the distribution date described in the Plan. /s/ Brian K. Shore, Attorney-in-Fact, for Arcilia Acosta 2018-08-22