For almost five decades, Rock Levinson has remained a loyal landline customer of CenturyLink, going back to the days of Mountain Bell.
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He is now on the verge of cutting the phone cord — or having it cut — because of what he calls a “mystery” letter that appeared in July.
CenturyLink asked him to sign up for a new wireless option called Connected Voice with Air-Line if he wanted to keep his home’s phone service.
“The issue for us is whether we can use our existing landline equipment. That is something convenient, and it works with several handsets,” he said.
CenturyLink is asking long-time residential customers, like Levinson, to switch over to a wireless option because it can no longer use the fiber optic network that it sold last year to AT&T.
CenturyLink has requested permission from the Federal Communications Commission to discontinue its existing voice service using fiber to customers from Fort Collins to Fountain, effective Aug. 24.
The company claims that there are at least 10 other options for consumers seeking replacement phone service. The number of customers impacted was not disclosed.
Eventually, the company plans to shut down what remains of its copper phone network, although a timeline hasn’t been provided.
As it loses or decommissions the wires needed to transmit calls, the company is shifting the dwindling number of customers who remain to a wireless option.
Air-Line uses a small adapter that routes calls to a nearby cellular tower rather than through a copper or fiber line. If one tower is overloaded, it can switch to a nearby alternate. Existing equipment, whether corded or cordless, plugs into the small box and remains functional. The original number works and the service sounds the familiar dial tone, while maintaining caller ID and other landline features. A battery backup can be added to keep the line active during a power outage.
The letters, per federal law, must give consumers a minimum of 90 days to switch their service to the wireless option or to find another provider.
Levinson already has cellular service and a high-speed Internet connection with AT&T, which purchased CenturyLink’s consumer fiber network last year.
That handoff is why Levinson and other consumers along the Front Range who retained CenturyLink landlines are now receiving letters asking them to make the switch.
“CenturyLink is planning to stop offering legacy voice service over fiber cable in certain Colorado communities, as we have sold these fiber lines to AT&T,” said CenturyLink spokesman Ron Boehmer.
Although it provided a grace period, AT&T won’t let CenturyLink keep using the fiber network it now owns. And CenturyLink can’t or doesn’t want to go back to using the old copper network.
AT&T doesn’t want to deal with Plain Old Telephone Service, also called POTS, which uses analog voice lines powered directly by copper wires.
Pretty much every telecom company, including CenturyLink’s parent Lumen Technologies, wants to get off POTS as fast as they can.
That is why CenturyLink is encouraging customers with voice service, whether fiber or copper, to explore Connected Voice with Air-Line or to consider alternatives.
“Copper is fast becoming obsolete. We strongly encourage customers to proactively explore transitioning to modern alternatives, including CenturyLink Connected Voice with Air-Line, as well as voice and internet through other providers’ fiber, cable, wireless, or satellite services,” Boehmer said in an email.
He adds that the FCC has approved the device as an “adequate replacement” for existing service. It is designed for customers who want to keep their existing number and handsets and who want full support for 911 calling and medical alert systems.
Copper sunset ahead
As recently as 2004, about 9 in 10 adults lived in households that still had landlines, almost entirely copper-based, while 5% were wireless only.
Today, nearly 79% of U.S. adults live in wireless-only households, according to the . About 20% of adults are dual-users, and under 2% are landline only.
In Colorado, landline-only households are even rarer at 1.3% of adults, and they predominantly contain people aged 65 and above.
While 1.3% sounds small, statewide, that represents roughly 31,000 Colorado households–and around 16,000 across the Denver metro area—that rely exclusively on a landline with no cell phones in the home.
CenturyLink hasn’t operated its own cellular network since the early 2000s. But that technology, via third-party providers, will be how calls for its residential phone customers are handled in the future.
CenturyLink designed Air-Line to be a plug-and-play option that would be easy for someone with minimal tech skills to install.
Levinson, however, said a good friend complained to him over dinner about a frustrating two days spent trying to get the box to work.
A CenturyLink technician eventually came out and couldn’t get it working either, and told his friend the problem was on the company’s end and would take a week to resolve.
“After hearing his story, we are going to bite the bullet and go with our cell phones from now on,” he said.
Consumers who received the letter that Levinson did can accept CenturyLink’s Air-Line Box; they can add an AT&T Digital Phone if they have AT&T broadband service, or they can cut the cord and go with a third-party provider or mobile phone service.
CenturyLink told the FCC in its filing that more than 10 different options are available for phone service.
What consumers can’t do is go back to the way things were. CenturyLink finds itself maintaining aging and expensive copper networks serving a declining number of customers. And it wants out.
Copper lines are vulnerable to weather, corrosion and to theft motivated by high metal prices. They are also self-powered, consuming increasingly expensive electricity.
Lumen has been filing notices to decommission its copper phone networks in Colorado and elsewhere with the FCC.
Although a filing hasn’t been made for Denver, including the Park Hill neighborhood where Levinson resides, it is likely only a matter of time.
“While we continue to evaluate which areas will be decommissioned, we currently have no schedule to decommission our mass market consumer copper lines in the Denver area,” Boehmer said.
Should that change, customers will be given advance notice and help in finding alternatives before they lose service, he said.
Last year, the FCC streamlined its rules to speed up the copper decommissioning process. Carriers argued the move frees up capital for modern broadband and reduces regulatory drag.
But consumer advocates warn that it lowers the bar for what qualifies as an acceptable replacement service, leaving long-time customers vulnerable to a “less than” scenario. One key point of contention is the always-on service that copper provides in power outages and extended emergencies.
Carriers have a strong incentive to get their customers to switch and can win faster approval to shut down a copper network if no circuits are active, meaning no more customers.
One by one, legacy networks will shut down in what industry analysts describe as the “copper sunset.”
The final step will likely come when Lumen asks the Colorado Public Utilities Commission to relinquish its Carrier of Last Resort (COLR) status.
As a condition of having monopoly status in a community, phone companies agreed to provide basic landline services to any home in their territory, no matter how remote.
Lumen has tried to relinquish its last resort status in Utah and California, but has been met with stiff resistance. It wants the FCC to preempt California regulators.
Utah regulators are concerned that CenturyLink’s options for replacement services aren’t comparable to copper landlines, that rural areas would lose coverage, and that network modernization won’t be completed.
CenturyLink hasn’t requested a last resort relinquishment in Colorado, where it will likely face stiff resistance. But it doesn’t need that to shut down its copper networks.
On the day relinquishment comes, the funeral bells will finally ring on a long history of copper phone service in the state.
Colorado and copper married young
Alexander Graham Bell patented the telephone about five months before Colorado became a state. Within three years, phone service was available in Denver, making the city a telecom pioneer, a reputation it holds to this day.
Entrepreneur Frederick Vaille convinced an initial group of 161 customers to try the new technology and set up a switchboard above Conrad Frick’s shoe store at 15th and Larimer streets, according to the Colorado Virtual Library.
He built the first major telephone exchange between the Mississippi River and the Pacific Coast, and phone service spread quickly into Colorado’s booming mining towns and up and down the Front Range.
Vaille formed the Colorado Telephone Co. in 1881 as a franchisee of the American Bell Telephone Co., which would later become AT&T.
In 1911, AT&T would wrap its Colorado operations into a larger regional company called The Mountain States Telephone and Telegraph Co., more commonly referred to as Mountain Bell or Ma Bell.
When anti-trust regulators broke up AT&T’s local phone service in 1984, Mountain Bell became part of Denver-based US West, one of the “Baby Bells.”
Qwest Communications bought it for $56 billion in June 2000, and CenturyLink bought Qwest for $22.4 billion in April 2011 and rebranded as Lumen Technologies in 2020.
Adequate replacement service
A fiber optic connection to the home is considered the gold standard for broadband service, and earlier this decade, CenturyLink aggressively built out its consumer fiber network along the Front Range.
Fiber allows for dedicated connections with minimal interference and extremely fast speeds in both directions. The network upgrade allowed CenturyLink to better compete with cable and cellular rivals.
It also helped build a strong case that the company’s copper customers weren’t just getting an “adequate” replacement but a superior one.
But installing fiber is expensive, and Lumen had large debts it needed to repay. In May 2025, AT&T agreed to purchase Quantum Fiber for $5.75 billion in cash, minus the copper network.
Complicating the transition, CenturyLink’s fiber phone lines aren’t compatible with the AT&T network.
Former CenturyLink phone customers who have high-speed Internet with AT&T can sign up for AT&T Phone or a third-party provider like Vonage.
Those services use a Voice over Internet Protocol or VOIP, a more affordable alternative to traditional landlines. But VOIP operates differently from landlines, and older customers may not be as comfortable with it or with its vulnerability during power outages.
In terms of technology, however, fiber is considered superior to wireless and to copper.
“Most folks would say that fiber is the technology they would rather have,” said Angela Siefer, executive director of the National Digital Inclusion Alliance. “It is the most reliable and future-proof of the technologies.”
Carriers, however, have to pick and choose what neighborhoods get improved connectivity first, and historically those have tended to be areas with higher-income residents, Siefer said.
BroadbandNow estimates that a little over half of Colorado households have access to a direct fiber connection, with coverage reaching closer to 60% in some metro Denver neighborhoods.
In June, AT&T Colorado president LJ Godfrey said in a release that the company was aggressively building out its fiber network in Colorado and across the nation.
AT&T plans to invest $250 billion nationally to reach 60 million locations by the end of 2030. Aurora, Boulder, Colorado Springs, Denver, Fort Collins, Greeley and Pueblo are among the Colorado cities targeted.
In locations that remain outside the reach of fiber, AT&T offers a fixed wireless option with much slower speeds.
For example, AT&T Internet Air advertises speeds of up to 300 Mbps, while the premium fiber option can reach 8 Gbps, about 26 times faster.
The company hasn’t provided details on which additional neighborhoods will be connected and when new areas can expect to receive fiber service.
All of those things would allow consumers to make a more informed decision. Nor has AT&T committed to full fiber coverage, a key step in ensuring digital inclusion.
Siefer said if some neighborhoods remain stuck with a slower and less reliable fixed wireless option, while surrounding areas receive superfast fiber, that will be a problem.
The federal government is investing heavily to ensure rural areas receive better connectivity, and the Colorado Broadband Office has a $420.6 million allocation to work with.
Because of that investment, Siefer said the digital divide could shift from rural vs. urban to wealthier vs. poorer neighborhoods in populated metro areas.
Federal regulations require that there be one or more adequate replacement services available before any telecommunications provider can decommission copper lines, Boehmer said.
“No CenturyLink customer will be left without an option,” he emphasized.
In 2014, Colorado lawmakers deregulated retail landline phone service, stripping the state Public Utilities Commission of its power to cap basic rates or enforce service quality standards.
Phone companies that received state and federal funds from the High Cost Support Mechanism (HCSM) to provide service in high-cost rural areas, however, still had to request state approval to shut down a copper network, said PUC spokeswoman Megan Castle.
“CenturyLink stopped accepting HCSM funding several years ago, however, and is therefore no longer subject to those rules,” Castle said in an email. “As a result, CenturyLink is no longer required to file notice with the PUC or request permission to discontinue services.”
Any requests to end a landline network go through the FCC, which critics argue has lowered its standard for consumer protections in its push to speed up the transition to newer technology.
Consumers must receive written notice at least 90 days before copper networks are decommissioned. They must also receive “functional” alternatives, full access to emergency 911 services and a battery backup option.
Consumers do not have a right to stay on copper, to receive a one-for-one technology match, or to be charged prices that match or beat what they were paying.
But they do have a on a provider’s request to eliminate service, which, in the case of CenturyLink, is available on the FCC website.
Colorado Attorney General Phil Weiser, the Democratic nominee for Colorado governor, said his office is watching the transition.
“We are concerned to hear reports that some consumers are not being provided with comparable or better replacement to the traditional landline service offerings they have relied on,” Weiser said in an email.
Consumers concerned about how they are being treated can file a complaint with stopfraudcolorado.gov.
“We will evaluate whether consumers are being treated unfairly and illegally,” he said.
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