Start Service If you are a residential customer, you can setup your electric or gas service online. In addition to your new address, to get started you'll need: A Social Security Number, An active email address, and An active phone number. An Eversource.com User ID and password. If you do not have one you can register now. Start Service If you are a business customer and would like to start service, please call our Business Center at 800-340-9822. You'll need to provide the legal name of your business, your Tax ID number and contract information.