The sunsetting of the Plain Old Telephone Service (POTS), the transition from traditional analog phone systems running on copper wires to digital VoIP and fiber technology, is picking up pace around the globe. In Europe – Portugal, Spain, and Sweden will force companies off copper lines this year, while UK enterprises have until 2027 for full network switch-off. In the US, the switch-off is less uniform, as it varies state by state, carrier by carrier. There, the pressure to migrate is being pushed through by a more immediate mechanism: dramatic price increases that are making POTS lines and service economically untenable.
“Prices have gone from $40 to $50 a month per line to over $100 a month per line in a lot of markets,”
Lathan Lewis, Head of Products at Tango Networks, explains. Whether it is due to closing networks or increasing costs, it is clear a migration away from POTS is necessary.
The problem is that many companies have deep hardware investments tied to POTS lines and until now, have not found a reliable alternative communications capability. Moving off POTS ostensibly means replacing all that investment and introducing operational disruption.
For enterprises with multiple locations, that translates into a significant capital expenditure problem. But there’s an alternative that avoids wholesale replacement: keeping existing hardware in place while eliminating both the sunset deadline and escalating costs.
Why Legacy Infrastructure Creates a Migration Dilemma
POTS has been embedded in enterprise operations for decades. It’s not just desk phones. It’s fire alarm panels, elevator emergency systems, building entry controls, and PA networks spread across facilities. For a small business with a handful of lines, replacement might be painful but manageable. For an enterprise with dozens of locations and hundreds of endpoints, the cost becomes prohibitive.
This reality sees many US companies choosing to absorb rising monthly POTS charges rather than face wholesale hardware replacement, leaving the big expense and disruptive infrastructure overhaul to the last minute. In the UK, a similar reluctance to migrate was significant enough that Openreach and BT delayed the PSTN sunset by two years specifically to give vulnerable users and critical systems (alarms, telecare devices, emergency phones) more time to transition.
But delays only postpone the inevitable. Copper infrastructure is disappearing, carriers have no incentive to maintain it, and prices will keep climbing. The question isn’t whether to migrate. It’s how to do it without breaking the budget or disrupting operations. The answer lies in rethinking what actually needs to change: not the hardware itself, but how it connects to the network.
How Tango Extend Preserves Hardware While Eliminating POTS Costs
Rather than replacing functioning equipment, Tango Extend offers a way to keep existing infrastructure in place while moving connectivity off expensive copper lines. This eliminates both the cost of replacement and the disruption that an overhaul brings.
Tango Extend can be deployed on these POTS-linked devices by switching out the copper line for an analog telephone adapter. This adapter can then accept a SIM card or connect via Ethernet to link the device to modern mobile connectivity.
The approach is straightforward, with Lewis explaining that;
“It’s just converting the old analog device to run on cellular. You just take the copper line out, and plug in the box,”
This way, the existing hardware remains operational. What changes is how they connect to the network.
This shift in connectivity delivers three critical benefits.
- First, it dramatically reduces costs. Lewis breaks down the economics: “Let’s say you’re paying $100 a line now for POTS because your price went up. Using our solution for that same application would be $5 or less per month per box.” For a company with 50 POTS lines, that can equate to thousands of dollars saved per month in ongoing costs.
- Second, it addresses the sunset deadline. By moving connectivity to mobile networks, companies eliminate exposure to carrier timelines and forced migrations.
- Third, the mobile solution fully integrates with existing UC platforms, allowing companies to extend monitoring of the communications to and from these emergency systems. As Lewis explains: “Companies that monitor and maintain routing for all their desk phones may want to do the same for calls made on emergency call boxes and other legacy endpoints. With our solution, if a call is made on them, the company can see it, get notifications, and then can decide to take action.” For organizations with compliance or safety-critical infrastructure, this unified visibility across all endpoints is a welcomed upgrade.
Importantly, Tango Extend’s approach delivers superior performance compared to other cellular alternatives. Many companies initially tried using basic IoT data SIMs for POTS replacement, but voice quality suffered because calls were routed over data connections. Tango Extend uses high-priority mobile voice channels, which provide voice-optimized connectivity rather than treating calls as generic data traffic.
Lewis emphasizes why this distinction matters:
“If you have an emergency call box, you need to be able to clearly hear whoever’s calling in to the emergency answering point there. So that’s where having VoLTE is critical.”
For life-safety systems where communication clarity can’t be compromised, this distinction is crucial.
Act Before Deadlines and Costs Force Your Hand
The POTS sunset isn’t a distant threat. Carriers are actively retiring infrastructure, prices are climbing month by month, and waiting means paying more while migration becomes increasingly urgent and less strategic.
The connectivity to preserve hardware investments, eliminate exposure to copper line retirement, and slash costs by thousands of dollars exists today.
Organizations can therefore act now on their own terms, or wait until carrier deadlines and runaway costs eliminate the choice.
- Cut Costs, Increase Usage: What Happens When You Ditch Desk Phones for a UC-Integrated eSIM Solution
