An electrical contractor is a business person or firm that contracts to carry out electrical installations, constructions, or repairs. They are licensed and insured to cover their contract work. They typically employ licensed electricians to carry out the work.

Inside contractors provide electricity to buildings and structures. They can serve as prime contractors for all electrical design, installation, and maintenances in commercial, institutional, and residential buildings.

Integrated building systems contractors work with low-voltage installations, such as fiber optics, back-up power, energy-efficient lighting, climate controls, wireless networks, security systems, and telecommunications. They work to integrate these system controls for maximum energy efficiency.

Line contractors are responsible for high-voltage power transmission and distribution lines. They see that electricity generated at power plants is safely carried through high-voltage lines and substations all the way to the consumer.