X0306 4 2021-12-27 1 0001587732 ONE Gas, Inc. OGS 0001283387 NORTON PIERCE 15 E. 5TH STREET TULSA OK 74103 0 0 0 1 See Remarks Common stock, par value $0.01 2021-12-27 4 M 0 3820 75.49 A 264664 D Common stock, par value $0.01 2021-12-27 4 F 0 1695 75.49 D 262969 D Common stock, par value $0.01 2021-12-27 4 M 0 1960 75.49 A 264929 D Common stock, par value $0.01 2021-12-27 4 F 0 870 75.49 D 264059 D Common stock, par value $0.01 2021-12-27 4 M 0 694 75.49 A 264753 D Common stock, par value $0.01 2021-12-27 4 F 0 308 75.49 D 264445 D Restricted Units 2019 2021-12-27 4 M 0 4527 75.49 D Common stock, par value $0.01 4527 0 D Restricted Units 2020 2021-12-27 4 M 0 4158 75.49 D Common stock, par value $0.01 4158 0 D Restricted Units 2021 2021-12-27 4 M 0 6053 75.49 D Common stock, par value $0.01 6053 0 D In conjunction with Mr. Norton's retirement on June 27, 2021, distribution of restricted units awarded under Issuer's Equity Compensation Plan. The restricted units vested on a pro-rata basis, determined by multiplying the number of restricted units awarded by a fraction, which fraction was equal to the number of full months which lapsed under the restricted period at the time of retirement (28 months) by the number of full months in the restricted period (36 months). The remaining 1,006 restricted units awarded were forfeited. The award vested on December 27, 2021, six months following the date of retirement, at the fair market value of issuer's stock on the date of retirement of $75.49. The award was payable one share of Issuer's common stock for each vested restricted unit and accrued dividends of 299 shares. In conjunction with Mr. Norton's retirement on June 27, 2021, distribution of restricted units awarded under Issuer's Equity Compensation Plan. The restricted units vested on a pro-rata basis, determined by multiplying the number of restricted units awarded by a fraction, which fraction was equal to the number of full months which lapsed under the restricted period at the time of retirement (16 months) by the number of full months in the restricted period (36 months). The remaining 2,310 restricted units awarded were forfeited. The award vested on December 27, 2021, six months following the date of retirement, at the fair market value of issuer's stock on the date of retirement of $75.49. The award was payable one share of Issuer's common stock for each vested restricted unit and accrued dividends of 112 shares. In conjunction with Mr. Norton's retirement on June 27, 2021, distribution of restricted units awarded under Issuer's Equity Compensation Plan. The restricted units vested on a pro-rata basis, determined by multiplying the number of restricted units awarded by a fraction, which fraction was equal to the number of full months which lapsed under the restricted period at the time of retirement (4 months) by the number of full months in the restricted period (36 months). The remaining 5,381 restricted units awarded were forfeited. The award vested on December 27, 2021, six months following the date of retirement, at the fair market value of issuer's stock on the date of retirement of $75.49. The award was payable one share of Issuer's common stock for each vested restricted unit and accrued dividends of 22 shares. Retired Director, President and Chief Executive Officer /s/ Brian K. Shore, Attorney-in-Fact for Pierce H. Norton 2021-12-29