EXHIBIT 21
The Company’s principal affiliates are listed below. All other affiliates, if considered in the aggregate as a single affiliate, would not constitute a significant subsidiary.
SUBSIDIARIES OF REGISTRANT
(As of February 26, 2026)
Acero Prime, S. de R.L. de C.V., a limited liability company formed under the laws of Mexico
Admiral Metals Servicenter Company, Incorporated, a Massachusetts corporation
Aleaciones Especiales de Mexico, S. de R.L. de C.V., a limited liability company formed under the laws of Mexico
All Metal Services Limited, a private limited company formed under the laws of the United Kingdom
All Metal Services (Malaysia) Sdn. Bhd., a private company limited by shares formed under the laws of Malaysia
American Alloy Steel, Inc., a Texas corporation
American Metals Corporation, a California corporation
AMI Metals, Inc., a Tennessee corporation
AMI Metals Europe SRL, a limited liability company formed under the laws of Belgium
AMI Metals France SAS, a simplified joint stock company formed under the laws of France
AMI Metals UK Limited, a private limited company formed under the laws of the United Kingdom
Best Manufacturing, Inc., an Arkansas corporation
CCC Steel, Inc., a Delaware corporation
Chapel Steel Corp., a Pennsylvania corporation
Chapel Steel Canada, Ltd., a corporation formed under the federal laws of Canada
Chatham Steel Corporation, a Georgia corporation
Clayton Metals, Inc., an Illinois corporation
Continental Alloys & Services Limited, a private limited company formed under the laws of the United Kingdom
Continental Alloys & Services (Malaysia) Sdn. Bhd., a private company limited by shares formed under the laws of Malaysia
Continental Alloys & Services Pte. Ltd., a private company limited by shares formed under the laws of Singapore
Continental Alloys Middle East FZE, a free zone establishment formed under the laws of the United Arab Emirates
Crest Steel Corporation, a California corporation
Diamond Manufacturing Company, a Pennsylvania corporation
DuBose National Energy Fasteners & Machined Parts, Inc., a North Carolina corporation
DuBose National Energy Services, Inc., a North Carolina corporation
Durrett Sheppard Steel Co., Inc., a California corporation
Earle M. Jorgensen Company, a Delaware corporation
Feralloy Corporation, a Delaware corporation
Fry Steel Company, a California corporation
Infra-Metals Co., a Georgia corporation
Liebovich Bros., Inc., an Illinois corporation
Metalweb Limited, a private limited company formed under the laws of the United Kingdom
Mid-West Materials, Inc., an Ohio corporation
Northern Illinois Steel Supply Co., an Illinois corporation
Nu-Tech Precision Metals Inc., a corporation formed under the laws of Ontario, Canada
Pacific Metal Company, an Oregon corporation
PDM Steel Service Centers, Inc., a California corporation
Phoenix Corporation, a Georgia corporation
Precision Flamecutting and Steel, Inc., a Texas corporation
Precision Strip Inc., an Ohio corporation
Reliance Metalcenter Asia Pacific Pte. Ltd., a private company limited by shares formed under the laws of Singapore
Reliance Metals Canada Limited, a corporation formed under the federal laws of Canada
Service Steel Aerospace Corp., a Delaware corporation
Siskin Steel & Supply Company, Inc., a Tennessee corporation
Southern Steel Supply, LLC, a Tennessee limited liability company
United Pipe & Steel Corp., a Delaware corporation
Valex Corp., a California corporation
Valex Korea Co., Ltd., a corporation formed under the laws of the Republic of South Korea
Valex Semiconductor Materials (Zhejiang) Co., Ltd., a limited liability company formed under the laws of the People’s Republic of China
Viking Materials, Inc., a Minnesota corporation
Yarde Metals, Inc., a Connecticut corporation