Acerinox, S.A. (Spanish pronunciation: [aθeɾiˈnoks]), headquartered in Madrid, is a manufacturer of steel and related products. In 2022, it was the 4th largest producer of stainless steel worldwide. It has operations in Europe, Asia, the U.S., and South Africa. It has fifteen factories including five in its stainless steel division. The company has been focused on increasing production in the U.S.