If you’ve been tracking the POTS sunset across the country, California just became the most important story in telecom.
In May 2026, AT&T filed a federal lawsuit against the California Public Utilities Commission (CPUC) and the state attorney general, seeking a court order to end its obligation to offer traditional copper-wire telephone service, what the industry calls POTS, or “plain old telephone service,” to new customers in the state. It’s the most aggressive move yet in a nationwide POTS sunset that has been building for years.
The numbers behind the lawsuit make the case for copper retirement plainly: AT&T spends approximately $1 billion per year maintaining a copper network that now serves just 3% of households in its California service territory. The POTS sunset isn’t a future event for AT&T. It’s already happening — and the regulatory framework is the only thing slowing it down.
Why AT&T Is Forcing the POTS Sunset in California Now
AT&T isn’t new to this fight. Two years ago, in June 2024, the CPUC rejected AT&T’s request to be relieved of its Carrier of Last Resort (COLR) obligation — the rule requiring it to provide basic telephone service to any customer in its territory who asks. The lawsuit is AT&T’s attempt to take the POTS sunset fight to federal court.
The timing is significant. The FCC recently adopted rules encouraging carriers to accelerate copper network retirement, and AT&T has already secured regulatory relief for the POTS sunset in 20 of the 21 states where it operates traditional copper networks. California remains the lone holdout.
Alongside the lawsuit, AT&T filed a petition with the FCC asking the agency to declare California’s copper mandate preempted by federal standards. The company has simultaneously committed to invest $19 billion in California through the end of the decade, upgrading more than 4 million additional households and businesses to fiber — the clearest signal yet that the POTS sunset is being funded, not just planned.
Copper Networks Are Already Failing — With or Without a Court Order
Beyond the regulatory battle, AT&T’s lawsuit points to a practical reality driving the POTS sunset nationwide: copper infrastructure is becoming impossible to maintain.
California has already experienced approximately 2,000 outages tied to copper theft in 2026 alone. Copper wire has value as scrap metal, and theft from telephone infrastructure has become a persistent and escalating problem wherever aging copper networks remain in the ground. Each theft creates an outage. Each outage requires a repair. And those repairs are getting harder to make.
The manufacturers that built hardware for legacy telephone networks are either out of business or no longer producing the specific components these systems require. Parts for copper phone infrastructure are increasingly scarce — and that scarcity will only worsen as the POTS sunset advances.
What the POTS Sunset Means for Businesses Still on Analog Lines
Whether AT&T wins this lawsuit or not, the POTS sunset trajectory is the same: copper is going away. The question isn’t if — it’s when, and whether your business will be caught flat-footed when your carrier finally pulls the plug.
Life-safety systems are the most exposed. Elevator phones, fire alarm panels, emergency call stations, and access control systems built around traditional analog lines don’t automatically migrate when copper disappears. In heavily regulated environments — schools, healthcare facilities, multi-tenant buildings — a failed POTS replacement can mean compliance violations, failed inspections, or worse.
At MIX Networks, POTS sunset planning is what we do. Our POTS replacement solutions are purpose-built for organizations that need their critical communications to keep working regardless of what carriers do with their legacy infrastructure. Our DataRemote 90X1 and 90X2 devices — dual-certified by both the FDNY Bureau of Fire Prevention and the California Office of the State Fire Marshal — are specifically engineered for fire and life-safety applications that require proven, code-compliant alternatives to copper analog lines.
The POTS Sunset Bottom Line
AT&T’s California lawsuit is the loudest signal yet that the copper era is over. Carriers nationwide are reaching the same conclusion: spending billions to maintain aging analog infrastructure for a shrinking base of users is not sustainable. Regulatory battles may shift the POTS sunset timeline by months. They won’t reverse the direction.
If your business relies on POTS lines for voice communications, alarm monitoring, elevator compliance, or any other purpose — now is the time to plan your POTS replacement. Not when your carrier sends a discontinuation notice. Now.
MIX Networks can help you build a POTS sunset migration plan that protects your operations, satisfies your compliance requirements, and keeps your communications running through whatever the carriers decide next.
