Eversource Energy
NiSource
National Grid plc
Avangrid
ISO New England
The United Illuminating Company
Énergir
Consolidated Edison
Dominion Energy
Hydro-Québec
Public Service Enterprise Group
Just Energy
Exelon
Former utility company in Massachusetts
nstar.com
NSTAR was a utility company that provided retail electricity and natural gas to 1.4 million customers in eastern and central Massachusetts, including the Boston urban area. Wikipedia