The labor cost to install an electrical supply box typically ranges from $500 to $1,500, depending on the complexity of the project and local rates. Understanding distribution box cost involves examining the comprehensive investment required for electrical distribution systems that serve as crucial infrastructure components in residential, commercial, and industrial settings. Key cost drivers include panel amperage, indoor vs outdoor location, wiring length, and whether a full panel upgrade or rerouting is needed. The article outlines cost ranges, per-unit pricing, and practical. The Suggested Retail price column, also referred to in the industry as the third column, end column or best column are the manufactures' most current published prices. The Average Cost column represents the national average purchase prices and is to be used as a guide to competitive pricing. Average markup 30-50% on materials.