Energy services company

Energy services companies, or ESCOs, evolved in the regulated model to offer services beyond the regulated services offered by utility companies. Typical ESCO services include bill evaluation, demand side management, appliance maintenance, power reliability, and power quality. These services are provided by numerous for-profit organizations, both large and small, and are in addition to regulated services offered by utilities.

In competitive markets, ESCOs continue to provide an important market function. In addition to providing the services described in the vertically integrated market model, they may also assist larger end-use customers in evaluating the various market options and finding optimal solutions for acquiring supply and satisfying gas and electric needs.  

Although the term ESCO does not typically refer to a retail marketer that sells supply, it is used to describe retail marketers in the state of New York.