Potential Impacts on Telephone Service during De-Energization

You may receive different levels of telephone service when your provider loses power. Telephone service providers must under Decision 10-01-026 have programs to educate you on different backup power supplies and how to get them.

Will my telephone work in a de-energization event? It depends.

• If you have a wireline and subscribe to POTS (plain old telephone service) voice service using copper lines, you will generally have service during a power outage. This is because the central office serves the residence as backup power, which provides the electricity necessary to run a wired telephone during a power outage.
  • We do not have rules mandating backup power for this service. However, most central offices maintain backup power.
  • Cordless phones need you to maintain the batteries in those devices, so that the home portion of the telephone service can work in a power outage.
• If you are a VoIP customer, service during a power outage depends on the provider’s underlying facility. Some VoIP providers will maintain line power (some variants of DSL) during an outage, and others rely on network power, which may or may not be present.
• If you have cable with voice service, you may or may not have service in a power outage.
  • We do not have rules mandating backup power for this type of service.
• If you have a wireless (cellular) phone, you may or may not have voice service in a power outage, depending on the backup power installed at cell sites.
  • We do not have rules mandating backup power for this type of service.
• It is your responsibility to get the needed backup power in your home to have working telephone service during an outage event. This might include batteries for cordless phones, routers, WIFI, fiber termination devices, and other home equipment.

Does a phone provider have to provide service? Some do.

A service provider that is designed as a Carrier of Last Resort (COLR) must offer basic service to all residential customers in its territory under Decision 12-12-038, including free access to 9-1-1. This includes AT&T, Consolidated, Frontier, and 13 small rural carriers. View a list of all the COLRs and a map of their service territories.  

We do not have rules for service providers to keep telephone service operational during a planned power outage. If you have a complaint about your telephone service, first call your service provider. If they don’t fix it, please call the CPUC’s Consumer Affairs Branch at (800) 649-7570 to submit an informal complaint.

General Order 168 Rule 3 requires phone providers who offer end-user access to the public switched telephone network to provide access to 9-1-1 emergency services to all residential customers and wireless devices. Rule 3 does not require carriers to provide access to 9-1-1 during a power outage or de-energization event.

Resolution ESRB-8 requires electric utilities to make all practical attempts to notify and coordinate with all potentially affected phone service providers before and after a de-energization event.

Read more on our Press Release from Jul. 16, 2020: CPUC Requires Wireless Companies to Better Serve Customers in Emergencies.