Electrical Contractor in St. Louis | Denver Electrical Contractors | Electrical Contractors in Illinois | Electrical Contractors in California


Founded in 1902, Guarantee Electrical first showed the world what electricity could do by illuminating the 1904 World’s Fair, and then “guaranteeing” that it would work for the duration of the event at a time when electrification was still in its infancy. Today, we continue to build our legacy as a national leader in electrical engineering, preconstruction, electrical construction, building management systems, cutting edge electrical construction technology and methodologies, and project management. 

With four regional offices, Guarantee Electrical Company has the capability to meet any owner or contractor's project demands.   

As a member of the Federated Electrical Contractors (FEC) best practices network, Guarantee is able to provide support beyond our core regions by partnering with other electrical contractors across North America.  The FEC is an international network of leading electrical contractors dedicated to safely providing clients with the highest quality electrical and low voltage systems at competitive pricing, regardless of geographic location. 


St. Louis, Missouri 

3405 Bent Avenue 

St. Louis, Missouri 63116 

Phone: 314.772.5400 


Granite City, Illinois 

1500 Grand Avenue 

Granite City, Illinois, 62040 

Phone: 618.452.6122 


Denver, Colorado 

21250 East 31st Circle 

Aurora, Colorado 80011 

Phone: 303.373.2400 


Benicia, California 

P.O. Box 1365 

Benicia, California 94510 

Phone: 303.373.2400