X0609 4 2026-04-27 0 0001673985 AdvanSix Inc. ASIX 0002130016 Day Patrick C. false 300 KIMBALL DRIVE STE 101 PARSIPPANY NJ 07054 0 1 0 0 SVP, CFO 0 Common Stock, par value $0.01 2026-04-27 4 A 0 19019 23.66 A 19019 D Common Stock, par value $0.01 2026-04-27 4 A 0 19019 23.66 A 38038 D Grant of restricted stock units pursuant to the 2016 Stock Incentive Plan of AdvanSix Inc. and its Affiliates, as Amended and Restated, which are scheduled to vest in three equal annual installments on the first three anniversaries of the grant date. Grant of restricted stock units pursuant to the 2016 Stock Incentive Plan of AdvanSix Inc. and its Affiliates, which will vest in full on April 27, 2029. /s/ Achilles B. Kintiroglou for Patrick Day 2026-04-29