Exhibit 21.1

SUBSIDIARIES OF

PERIMETER SOLUTIONS, INC.

As of December 31, 2025

Subsidiary			Jurisdiction of Formation
3PO LLC			Delaware
Auxquimia S.A.U.			Spain
Biogema S.A.S.			France
First Response Fire Rescue, LLC			Delaware
H&S Transport, LLC			Delaware
Horn Holdings, LLC			Delaware
IMS DE Holdings, LLC			Delaware
Intelligent Manufacturing Solutions, LLC			Delaware
LaderaTECH, Inc.			Delaware
Perimeter Holdings, LLC			Delaware
Perimeter Intermediate, LLC			Delaware
Perimeter Solutions Canada Ltd.			Canada
Perimeter Solutions DE GmbH			Germany
Perimeter Solutions LLC			Delaware
Perimeter Solutions LP			Delaware
Perimeter Solutions North America Inc.			Delaware
Perimeter Solutions Suppressants LLC			Delaware
Perimeter US, LLC			Delaware
Phosphorus Derivatives Inc.			Delaware
PSNA Holdings, LLC			Delaware
PSNA Intermediate LLC			Delaware
River City Fabrication L.L.C			Delaware
Solberg Asia Pacific Pty Ltd			Australia
Solberg Scandinavian AS			Norway