[4][5] LyondellBasell was formed in December 2007 by the acquisition of Lyondell Chemical Company by Basell Polyolefins for $12.7 billion.

[9] In August 2006, Lyondell acquired Citgo's interest in the Lyondell-Citgo Refinery for $2.1 billion, and renamed the facility Houston Refining.

[24] That same year, Hurricane Harvey hit the United States and affected the company's Texas Gulf Coast operations.

[28] LyondellBasell and Odebrecht entered into exclusive talks for LYB to acquire control of Braskem in June 2018, but did not consummate the acquisition.

[31] That same month, it broke ground on the world's largest propylene oxide and tertiary butyl alcohol plant in Channelview, Texas.

[32] LyondellBasell also announced in September that it and its joint partner, Covestro, kicked-off a large investment project in Maasvlakte-Rotterdam, the Netherlands.

The Circular Steam Project incorporates an innovative technology into the existing production plant, to convert its water-based waste into energy and is an important contribution to the Dutch government's CO2 reduction targets.

[34] In April of 2022, LyondellBasell announced plans to shutter its Houston refinery by the end of 2023, following two failed attempts to sell it.

[38] In 2015, the American Heart Association recognized LyondellBasell's Cincinnati Technology Center with the Fit-Friendly Worksite Platinum Award.

[43] LyondellBasell's, among other petrochemical facilities at Berre-L'Étang, France, are regularly criticized in the French media[44][45][46] and by local authorities[47][48] for their large-scale flaring activities generating, among other nuisances, giant smoke plumes[45] with lengths reaching dozens of miles.

[47] The concomitant atmospheric pollution includes organic chemical compounds such as carcinogenic benzene, butadiene and toluene.