Becoming an IPES Provider: What Carriers Need to Know Before the TDM Sunset

Landline phone usage in the US has dropped 93% over the past 20 years. That says a lot about where voice networks are headed — and how fast. In fact, the sunsetting of legacy Time-division multiplexing (TDM) voice is accelerating around the world as carriers and regulators push to turn down copper networks by 2030.

Benefits of becoming an IPES provider:

• Lower network operating costs
• Faster provisioning
• Simplified regulatory obligations
• Support for cloud and unified communications
• Better customer experiences

For incumbents and competitive local exchange carriers (CLECs), the shift to all-IP networks has opened significant growth opportunities by offering broadband, VoIP, cloud communications and unified connectivity to residential, SMB and enterprise customers alike. Providers that plan their transitions strategically can also simplify operations, accelerate service delivery and position themselves for long-term growth.

With growing revenue opportunities and the rising cost of maintaining legacy equipment, more CLECs are treating the move to an Internet Protocol Enhanced Service (IPES) provider as the logical next step.

Becoming an IPES provider — a VoIP provider regulated by the FCC — enables a CLEC to retire legacy networks and transition to an IP-based environment in partnership with an IPES enabler. But the process isn’t simple. Without proper planning, you may be looking at porting delays, operational inefficiencies and frustrated customers.

The stakes extend well beyond the network itself. Businesses depend on uninterrupted voice connectivity for customer service, sales and emergency communications. Consumers expect reliable, secure voice service no matter what’s running underneath. A poorly managed migration can disrupt customer experiences, delay service activation and create operational headaches that ripple across the entire ecosystem.

The good news: Providers don’t have to navigate this shift alone. From managed services to outsourced migration support, there are proven paths to modernizing voice infrastructure without disrupting customers or draining internal teams. If you’re a legacy carrier managing a shrinking TDM network, the stakes— and opportunity — are significant.

Why the end of legacy voice matters

The decline of legacy voice networks has been decades in the making, and the TDM sunset is now within sight. Traditional copper phone lines in the US have fallen from 171 million to just 11.7 million over the past 20 years. Network operators are driving much of this shift, pouring investments into next-generation IP and 5G infrastructure that supports VoIP and other services at lower cost and higher efficiency.

Consumers and businesses are already there. According to the FCC Voice Telephone Services Report, only 25.5%³ of US residential lines are still switched lines, while 74.5% are now VoIP. Among businesses, VoIP lines represent the majority of all wireline voice connections.

Carriers aren't the only ones pushing this forward. Following similar moves by other nations, the FCC has proposed mandating the sunset of all TDM networks by 2028, a move aimed at modernizing communications infrastructure and eliminating carriers' need to run parallel TDM and IP interconnects. The economics already point the same direction: AT&T alone is estimated to spend $6 billion⁴ each year to keep its copper network alive for only 5% of its residential customers⁵ who still use it.

For CLECs, sunsetting TDM can accelerate the transition to an IPES business model and a fully IP-based network. Beyond the operational benefits and better end-to-end call quality, industry research⁶ indicates next-generation IP transport architectures may deliver up to 35% lower capital costs and 57% lower operating costs compared with legacy multilayer transport architectures.

Regulatory requirements are also lighter than what CLECs have faced in the past, promoting faster time to market. For many providers, the commercial and technical case alone justifies the effort.

Four keys to a successful IPES transition

Transitioning to an IPES raises four recurring challenges: customer migration, network cutovers, service continuity and numbering and porting. Getting these right helps protect customer trust while keeping you ahead of regulatory risk.

You’ll want to focus on the following areas.

1. Plan customer migrations carefully

Bulk porting can be the most painful part of an IPES transition. Delays or provisioning errors show up directly as interrupted service, delayed activations or failed number transfers — and the complexity only grows when you’re consolidating numbers from multiple existing Service Provider ID’s (SPIDs) into one. Setting up trading partners can take anywhere from days to months, and not all of them follow the same rules for releasing numbers to port out. Many still rely on manual processes, leading to additional swivel-chair work, more fallout and slower time to revenue.

The pre-migration phase is your best opportunity to eliminate legacy clutter. Reconciling your telephone number (TN) and subscription version (SV) inventory before migrating will surface inaccuracies and red flags that could otherwise slow everything down. Key pre-migration activities should include a thorough review of TN inventory, number portability and provisioning workflows, and bulk disconnects.

2. Protect service continuity through careful scheduling

Network cutovers live or die on pacing. Moving bulk ports too fast can overwhelm routing systems or disrupt competitive porting with other networks — while moving too slowly stalls the whole migration. Success depends on coordinating closely with trading partners, planning around Number Portability Administration Center (NPAC) maintenance windows, and understanding how many migrations and telephone numbers each window can support. Advance coordination helps prevent conflicts with other large-scale porting projects and reduces the risk of service disruption.

Once you’ve locked in your new IPES OCN/SPID, LEC profiles and rollout strategy, bring in IPES migration experts early. An experienced managed voice service provider can run the end-to-end transition, lower risk, protect the customer experience and help you avoid potential fines — while also building a clear change management and communication plan that keeps customers informed at every milestone.

3. Automate numbering, porting and ongoing operations

Without a consolidated, automated approach to number inventory and porting, CLECs face real operational and regulatory exposure. Manual or fragmented tracking means paying for orphaned numbers still provisioned in switches, while off-net numbers from third-party networks require separate auditing outside your own SPID. On top of that, carriers must reconcile inventory against LERG/NANP data, maintain robocall mitigation database compliance, update the Reassigned Numbers Database, submit numbering utilization and forecasting reports, and continue managing LRN changes, CNAM updates and network grooming.

That’s a lot to run manually. Many providers are turning to automation and managed services to reduce operational burden while improving accuracy and compliance.

An automation-first approach handles registration, contract, connectivity and system updates while keeping porting, ordering and inventory accurate by synchronizing data in real time. This will simplify compliance and streamline order management both during the transition and after.

4. Prepare for ongoing IPES responsibilities

Resellers entering the VoIP business bypass many of the legacy headaches CLECs face — but they still inherit responsibility once they become an IPES provider. As participants in the numbering ecosystem, they’re on the hook for ongoing telephone number management, call authentication and compliance with evolving FCC requirements. As those requirements keep shifting, providers with automated tools in place will have an edge over those still relying on manual processes. 

How an IPES transition partner can help providers get there

Nearly every provider starts its IPES transition with the same questions:

• How do we obtain FCC authorization without derailing the business?
• How do we manage numbering, NPAC and porting at carrier scale?
• How fast can we migrate without customer disruption?
• How do we stay compliant without building a telecom bureaucracy?

These questions lead many providers to seek the guidance of experienced managed service partners. From FCC readiness and SPID enablement to NPAC connectivity, numbering, porting and lifecycle management, expert teams reduce the operational burden and, just as importantly, bring proven processes and experience to identify potential issues before they impact customers or the business.

One SPID, millions of numbers, countless moving parts

One nationwide CLEC engaged TransUnion® to migrate from more than 20 CLEC SPIDs to a single IPES SPID, coordinating across seven NPAC regions, 141 LATAs and nearly 29 million telephone numbers. Over an 18-month period, TransUnion completed 383 NPAC migration jobs, consolidated 20+ SPIDs into 1, reduced 437 LRNs through inventory cleanup and automated critical operational workflows along the way.

Looking ahead

The all-IP future is close and the opportunity extends well past VoIP. According to Mordor Intelligence,⁷ the global unified communications market — voice, video conferencing, messaging andth  collaboration combined — will grow from $56.14 billion in 2025 to $175.83 billion by 2030, a CAGR of 25.65%.

The transition to IPES isn't simply a network modernization project. It's a chance to build a more agile, automated and future-ready communications business. Providers that start planning now will be better positioned to reduce costs, meet evolving regulations and deliver the reliable voice services customers expect in an all-IP world. TransUnion’s managed voice services team has guided many CLECs through their IPES transitions. Our experts bring decades of hands-on migration experience, deep knowledge of FCC requirements and upcoming mandates, and a track record of navigating complex, high-stakes transitions at scale. Beyond minimizing risk and lightening the transition load on internal teams, our team can continue supporting providers’ voice operations after migration.

Learn more about TransUnion Managed Services.