POTS lines or “Plain Old Telephone Services” are antiquated phone call communications services being discontinued because they are considered an end-of-life technology, no longer profitable for telecom providers. Eventually, all POTS services will be phased out or “sunset.”
The bad news is this can have a negative impact on organizations, particularly with the added stress of strict shutoff deadlines and financial penalties putting pressure on companies to upgrade their telecommunications systems. In the U.K. for instance, the infrastructure is being permanently turned off December 2025 (more on the big switch-off later) with some companies allowing no new service orders after September 2023.
The good news is many companies are saving money by making that transition.
In this article you’ll learn:
- The benefits of POTS lines replacements
- How much money you could save by transitioning POTS lines
- What to consider in your POTS migration
- A five-step plan for migrating to more modern alternatives
- How Tangoe helps companies transition their POTS lines
A quick note: The term PSTN is also used to refer to POTS lines, because POTS lines use Public Switched Telephone Network (PSTN) infrastructure.
Why are POTS, PSTN, and Copper Lines being Terminated?
POTS lines are being retired, the same way 3G and 4G networking is being replaced by 5G wireless networks. When the majority of clients want the newest, fastest generation of services, it no longer makes financial or business sense for providers to continue to support legacy technologies for the few still hanging onto them.
Demand is a core issue.
Think of POTS as the business equivalent of the traditional landline phone connections that were once prevalent inside residential homes. Just as homeowners are increasingly trading in their landlines for more modern digital voice technologies, companies are also modernizing their POTS line connections and PSTN services, namely upgrading to Voice over IP networks (VoIP).
How are Companies being Pressured or Forced to Convert their PSTN and POTS Lines?
Companies are being strongly encouraged and, in some cases, forced by providers to upgrade.
In the U.S., the real pressure comes from telecom carriers increasing the price of their POTS line services – sometimes as much as $800 per line. According to the Bureau of Labor, POTS charge rates increased 36% from 2010 to 2021, even as mobile phone rates have declined. Learn more about POTS lines price increases. Providers are also bringing their maintenance and support services to an end or refusing to renew contracts, making it more difficult or impossible for customers to hold onto their lines.
It should also be noted that a U.S. federal mandate from the FCC spawned many misconceptions and scare tactics, giving clients the impression that there would be a full-scale decommissioning of POTS services by a deadline of August 2, 2022. That was not the case; nonetheless, the strong-arm tactics continue.
In the U.K. legacy Public Switched Telephone Network (PSTN) technology services are being turned off in December 2025, forcing companies to migrate to new services, creating logistical challenges with a deadline and the implications of a strict cutover. The PSTN upgrade project is a national effort to transform the telecom industry. The vast majority of British businesses are on still dragging their heels in the PSTN upgrade with 77% of organizations having not yet prepared for the end date.
Sometimes, companies are pressured to modernize their telecommunications due to the changing times. Employees no longer use their desk phones like they did decades ago, and today’s mobile trends, hybrid work, and work-from-home business models generate a new and different set of business needs as well as a new level of user expectations.
How Many POTS Lines Still Exist?
POTS lines are still prevalent inside companies that have not yet updated their communications systems. Beyond just telephony, they are commonly used for alarm systems, elevators, and emergency-use phones to name just a few.
While the numbers are declining, there are still millions in operation. In fact, the Federal Communications Commission reports the number of POTS lines in the U.S. declined from 122 million in 2010 to 41 million in 2019.
Here at Tangoe, many of our clients are still working on their POTS migration plans. In fact, our Telecom Advisory Services, which provide telecom cost management consulting services, are helping them manage or migrate about 325,000 POTS lines.
What are the Benefits of a POTS or PSTN Digital Alternative?
In short, the biggest benefits of migrating to more modern telecom systems is time and money.
- Faster, more automated digital technology upgrades from cloud-based communications systems, VoIP phone systems and IP PBX systems
- Lower costs due to the savings gained from making the switch to more affordable mobile phone rates and avoiding the price hikes of POTS
- Modern telecom systems are also easier for IT teams to maintain, creating productivity benefits
Perhaps the biggest gain is a superior user experience — unified communications platforms bring instant messaging, video conferencing capabilities, and voice services all into one platform helping to increase productivity for employees.
In the U.K., the digital telephone switchover is also bringing forth the government’s new plan to invest £150M in 5G connectivity means that the country will more quickly be blanketed in high-speed connectivity even in remote areas. These upgrades will help make it increasingly easier for companies to transform their POTS or PTSN lines to reliable digital alternatives.
At the end of the day, businesses investing in VoIP and cloud-based communications are getting rid of antiquated, labor-intensive, and expensive services in order to gain a superior service, more productivity and cost savings.
How Much Money can I Save by Transitioning my POTS or PSTN Lines?
In most cases companies can lower their telecom costs due to the savings gained from switching to more affordable rates and avoiding the price hikes that are increasingly common with POTS services. Learn about the rising costs of POTS lines here.
Here at Tangoe we see companies save on average 15% to 30%.
The exact amount depends on the starting point. POTS line costs can vary widely, ranging from around $20 to $800+ per line per month (depending on the type, location, telecom carrier and whether the service is under contract or billed at tariff rates). If a company’s current costs are in the $20-$50 range savings may be less significant; however, if they are in the $100+/month range and they have a high quantity of lines, the savings can be quite substantial.
Results also depend on the number of POTS lines per location, as some POTS replacement solutions are designed for high-quantity discounts, so you can save more if you have 2 to 4 lines per location rather than a single POTS line.
What Should Companies Consider when Replacing their PSTN or POTS Lines?
Companies transitioning POTS lines should keep in mind some key considerations.
- First and foremost, take a proactive approach to POTS replacement, planning for a digital alternative, knowing where your copper lines are (using a telecom inventory management approach), and understanding how service decommissioning is affecting you.
- Most importantly, know when your provider plans to sunset POTS offerings, so you can define the window of time you will have replace them – a proactive plan is far better than scrambling!
- Don’t forget to consider how supply chain delays and high demands for hardware may impact your installation. Here at Tangoe, we’ve recently seen hardware lead times increase to 6 months.
A 5-Step Plan for POTS and PSTN Replacement
- Start with a full audit of your existing POTS lines or PSTN infrastructure as well as their costs. Defining your impacted services should be the first step in crafting a migration plan. Build your business case, understanding the cost savings and any productivity gains you can achieve from modern technologies – a professional cost-savings assessment can help you with this.
- Choose the type of technology you will upgrade to (SIP trunking, VoIP, unified cloud communications as a service, or SD-WAN for example) and the specific solution you will standardize on. Shop around and negotiate new and existing contracts with the aim of reducing costs and reallocating any savings to fund your new investments.
- Evaluate your IT network, including the capacity of your infrastructure and your ability to support high-performance digital communications – network modernization plans can take a significant amount of time!
- Establish a smooth migration plan that takes a phased approach but also transitions services without disrupting employee productivity and business continuity. Don’t forget that high demands for routers combined with hardware supply chain issues can slow delivery dates and installations. Turn times have already lengthened to 6 months and are expected to take even longer as more switch-off deadlines approach. In the U.K., the hard cutover date is December 2025.
- Consider the resources, partners, and support you’ll need to make the migration a success. Lean on managed service providers and consultants when necessary.
How Does Tangoe Help Companies with their POTS Lines?
Tangoe can assist companies both strategically and tactically execute and manage the transition of POTS lines. But more critically, Tangoe is the industry expert in understanding the alternatives available, helping IT and finance leaders pinpoint specifically how much they can save in a transition, based on our market price indexes and pricing intelligence gleaned from tracking and managing $34B in IT spending. With a clearer view into your situation, Tangoe can then outline a plan for companies to execute internally – or better yet — Tangoe can do the work on your behalf.
Tangoe can help you with:
- Auditing POTS lines and broader telecom expense audits: Tangoe can conduct a thorough inventory of POTS, DSL, PBX and other telecom services, so companies have visibility into their needs and the impact of retiring services.
- PSTN or POTS cost-savings assessment: Tangoe is the leader in guiding companies through an evaluation of their current prices and comparing them to market-competitive pricing for POTS alternatives delivering high-performance reliability and resilience.
- Negotiating new telecom service contracts: With 60 cost management consultants, Tangoe negotiates more than 400 IT service contracts for clients every year, achieving cost savings via provider consolidation, bulk or volume pricing discounts, and other strategies.
- Strategic and tactical plans to transition POTS lines: From understanding the differences between migrating to SIP vs PRI vs UCaaS to building an end-to-end migration approach, Tangoe has experience in smoothing the bumps and disruptions in service known to occur with POTS technology upgrades.
- Staff augmentation: When companies need more boots on the ground to turn their POTS plans into action, Tangoe can support you.
- Ongoing cost optimization programs for telecom services: Tangoe’s core competency is in giving companies the AI-powered analytics and automated platforms they need for both reducing the long-term telecom costs and accelerating the financial management tasks associated with them.