X0508 4 2026-02-27 false 0001489393 LyondellBasell Industries N.V. LYB 0002056904 Izquierdo Sabido Agustin 4TH FLOOR ONE VINE STREET LONDON X0 W1J 0AH UNITED KINGDOM false true false false EVP & Chief Financial Officer false Class A Ordinary Shares 2026-02-27 4 F false 713.00 57.52 D 13386.00 D Class A Ordinary Shares 2026-02-28 4 A false 20158.00 0.00 A 33544.00 D On February 27, 2026 the reporting person's restricted stock units automatically vested 2,819 shares. 713 shares were withheld by the issuer to satisfy the issuer's tax withholding obligations. Represents 6,240 restricted stock units ("RSUs") granted pursuant to the issuer's long-term incentive plan: 242 granted on February 22, 2024 that vest on February 22, 2027; 182 granted on April 15, 2024 that vest on April 15, 2026; 182 granted on April 15, 2024 that vest on April 15, 2027; 2,817 granted on February 27, 2025 that vest on February 27, 2027 and 2,817 granted on February 27, 2025 that vest on February 27, 2028. Represents 26,398 restricted stock units ("RSUs") granted pursuant to the issuer's long-term incentive plan: 242 granted on February 22, 2024 that vest on February 22, 2027; 182 granted on April 15, 2024 that vest on April 15, 2026; 182 granted on April 15, 2024 that vest on April 15, 2027; 2,817 granted on February 27, 2025 that vest on February 27, 2027 and 2,817 granted on February 27, 2025 that vest on February 27, 2028. The 20,158 RSUs reported on this Form 4 vest as follows: 6,720 vest on February 28, 2027, 6,719 vest on February 28, 2028 and 6,719 vest on February 28, 2029. /s/ Lara A. Mason, Attorney-in-Fact 2026-03-03