Skype Retirement 2025: The Real Reason Is a Network Upgrade (Not an App Migration)

On 5 May 2025, Microsoft retired the consumer version of Skype and is steering users to Microsoft Teams as its modern communications hub. 

On 14 October 2025, extended support for Skype for Business 2015/2019 ends. After that, no more security patches, bug fixes or technical support. 

At Skype’s peak, it had hundreds of millions of users. By early 2023, daily usage had fallen to about 36 million as enterprises shifted toward Teams and other UC tools. Teams has moved in the opposite direction, surging to roughly 320 million monthly active users by 2024 and remaining the backbone of modern work in 2025.

For IT Directors and CIOs, this “Skype dual retirement” is not just a forced application migration. It is a forced re-think of:

• How much bandwidth you really have
• How your VPN and WAN are architected
• Whether your connectivity is good enough for always-on video and collaboration
• How you secure and support a hybrid workforce that no longer sits behind a single MPLS link

Internal research from Spenza frames this as an “infrastructure evolution” rather than a simple app swap: moving from relatively lean, voice-centric workloads to cloud-native, video-first platforms that expose every weakness in legacy networks. 

Skype Shutdown 2025 vs Skype for Business End of Support Explained

The Consumer Skype Shutdown (May 5, 2025): Already Behind Us

The consumer Skype application officially shut down on May 5, 2025, ending 22 years of service. For small businesses, freelancers, and international contractors who relied on Skype numbers for cost-effective global communication, this created immediate operational disruption.

What Changed on May 5:

• The Skype application stopped functioning entirely
• Purchase of new Skype Numbers and credits ceased in early 2025
• Automatic renewals for existing numbers ended on April 3, 2025
• Users were directed to migrate to Microsoft Teams Free

Critical for SMBs: User data including chats and contacts will be retained until August 2025 or January 2026 depending on region and account type, providing a grace period for those who missed the May deadline. However, this window is rapidly closing.

For detailed guidance on understanding what happened and what you need to do now, see our comprehensive Skype Shutdown Explained guide.

The Enterprise Server Cliff (October 14, 2025): The Real Crisis for IT Leaders

Far more significant for mid-to-large enterprises is the approaching end of support for Skype for Business Server 2015 and 2019. Unlike the consumer shutdown, the server software won’t stop working on October 14—it becomes a “zombie asset”: functional but decaying, and dangerous to maintain.

What October 14, 2025 Means:

1. Security Vulnerabilities: Microsoft will cease all security updates, meaning any new vulnerability discovered after this date will remain unpatched forever. In an era where communication platforms are primary vectors for phishing and malware, this is unacceptable risk.
2. Compliance Failures: For industries regulated by HIPAA, GDPR, or SOX, operating unsupported software that handles sensitive communications constitutes a compliance failure, potentially leading to massive fines.
3. Degrading Interoperability: As Microsoft updates the cloud-side architecture of Microsoft 365 and Teams, interoperability with legacy on-premise Skype servers will degrade, breaking hybrid configurations.
4. Talent Shortage: Finding qualified personnel to maintain on-premises Skype servers is increasingly difficult as the workforce upskills to Teams certification.

Consumer Skype Retirement vs. Skype for Business 

The Confusion Factor: Why Clarity Matters

A primary challenge identified across enterprises is the conflation of these two deadlines. Many IT directors assumed the enterprise server would also stop functioning in May, leading to poorly planned migration sprints that risk destabilizing operations. While the October deadline allows for more measured migration strategy, the complexity of migrating server-based telephony to the cloud often requires 12-18 months of planning—meaning organisations starting now are already behind schedule.

Why “Just Switching to Teams” Fails

The single most costly mistake organisations make is treating the Skype-to-Teams migration as a simple software replacement. It is not. This is a networking and infrastructure project that happens to involve new software.

The Bandwidth Explosion: From Audio-First to Video-Everywhere

Skype for Business, especially on-premises versions, was architected for a different internet era, optimized for internal LAN traffic with limited external breakout or relying on heavily compressed, voice-centric codecs. Microsoft Teams, Zoom, and Google Meet are fundamentally different: cloud-native, video-first, bandwidth-intensive platforms demanding robust, low-latency connection to the public cloud.

Bandwidth Requirements Comparison

The Real-World Impact: An office with 100 employees on a Skype call might have saturated a 100 Mbps connection. Moving those same employees to a Teams video meeting will completely overwhelm the circuit, resulting in dropped calls, “robotic” audio, and frozen video streams. This is the “friction” that prevents successful migration—the failure of the network, not the software.

The VPN Hair-Pinning Problem: Legacy Architecture Meets Cloud Reality

In traditional setups using Skype for Business On-Prem, remote employees connected via VPN to the corporate data center where the Skype Server resided, with all traffic routing through this central point. This was efficient when the destination was on-premises.

The Teams Challenge: Teams lives in the Microsoft 365 cloud (Azure). If companies force Teams traffic through legacy VPN, data travels from the user through the encrypted tunnel to the corporate data center (hair-pinning), then out to the public internet to reach Microsoft’s cloud. This “trombone” effect doubles the latency and saturates the VPN concentrator with heavy video traffic it was never designed to handle.

The Solution: Split Tunneling and Direct Internet Access

IT directors are implementing “Split Tunneling”—network configurations allowing trusted traffic like Teams audio/video and SharePoint data to bypass the VPN and go directly to the internet, while sensitive corporate traffic remains in the secure tunnel. However, this exposes a new vulnerability: the reliability of the “direct to internet” connection.

For remote workers, this means complete reliance on home ISP connections—a critical point of failure that demands new solutions.

Quality of Experience (QoE): The New Network Performance Standard

Microsoft specifies strict thresholds for network performance: latency (Round Trip Time) under 60ms, jitter under 30ms, and packet loss under 1%. Skype had more robust mechanisms for dealing with internal network congestion or could be prioritized via MPLS tags within private WANs. In the shift to Teams, traffic traverses the public internet where QoS tags are often stripped by ISPs, requiring new approaches to guarantee performance.

The Four Business Risks If You Do Nothing

If you simply switch from Skype or Skype for Business to Teams or Zoom without revisiting your communications infrastructure, expect issues in four areas.

1. Bandwidth saturation and poor user experience

Symptoms you will hear within days of cutover:

• “Teams calls are dropping all the time.”
• “Video is unusable whenever someone joins from the conference room.”
• “Zoom webinars kill the internet for the entire office.”

Root causes often include:

• Shared broadband links at branches that were sized for email and web, not 50 video tiles
• No QoS or prioritisation for UC traffic
• Firewalls and proxies doing deep inspection on real time media flows

If your network was sized for 2015’s traffic, the 2025 migration will result in dropped calls and frozen video.

For a detailed technical breakdown, read our Skype vs. Zoom vs. Teams Comparison.

2. Hybrid work and the failure of home Wi Fi as a strategy

In many organisations, “remote connectivity strategy” is simply “let people use whatever broadband they have at home”.

That results in:

• Massive variations in performance based on where employees live
• Consumer grade routers that cannot handle simultaneous video, gaming and 4K streaming
• Unencrypted Wi Fi and shared networks that weaken your security posture

Internal Spenza positioning is blunt about this: employee home internet is not a corporate WAN. For critical workloads, you need managed connectivity that you can see, control and optimise, not hope.

3. Security and compliance exposure after Skype for Business end of support

Running Skype for Business Server past 14 October 2025 effectively means: 

• No security patches for new vulnerabilities
• No official support for incidents
• Increasing misalignment with current compliance requirements

Attackers routinely target unsupported platforms because they know patches will never arrive. Even with the optional six month ESU program, this only buys you time. It does not remove the need to migrate.

4. Telephony and number porting friction

If you are using:

• Skype numbers for inbound customer calls
• Direct SIP trunks into Skype for Business
• Legacy desk phones tightly coupled to on-prem PBX or SfB

Then you will also need to manage:

• Number porting from Skype or existing carriers into Teams Phone, Zoom Phone or SIP trunks
• Direct Routing or Operator Connect configurations
• Hardware compatibility and potential desk phone refresh

Spenza’s own guidance on how to port a Skype number breaks this down in business terms, but the key message is simple: start porting early, because porting timelines are often measured in weeks, not days.

How Companies Are Coping: Real-World Strategies & Best Practices

Here we outline the common approaches, coping mechanisms, and strategies organizations are using to handle the retirement and migration.

1. Auditing Current Infrastructure & Usage Patterns

• Many enterprises begin with a network & communication audit: check existing internet/ WAN bandwidth, latency, peak concurrent users, remote-staff connectivity, VPN loads, PSTN channels, inbound/outbound call volume.
• They assess usage patterns: how many users regularly do video calls, screen sharing, large group meetings; how many use PSTN/call-out, inbound numbers, etc.
• This insight helps forecast the bandwidth/ redundancy needed post-migration — and avoid under-provisioning.

2. Phased / Pilot Migration (Hybrid Approach)

• Rather than a “big bang” switch, many companies migrate gradually: pilot Teams/Zoom with small teams; test quality; gather feedback; then expand rollout. This allows them to catch network issues early, adjust QoS, circuit capacity, or user-training.
• During transition period, they may run hybrid communications — some employees on old VoIP/PBX or Skype alternatives; others on new UC tools.

3. Engaging a Connectivity / Infrastructure Partner — Outsourcing Network Upgrades & Support

• Realising internal teams may lack bandwidth or expertise, organisations collaborate with connectivity providers (like Spenza) to audit, upgrade, and manage their network infrastructure.
• Providers help with: high-bandwidth circuits, QoS, load balancing, redundancy, secure connections, scalable plans — ensuring that once tools like Teams or Zoom are deployed, the network can support them reliably.
• They also assist with PSTN bridging, number-porting, VoIP / SIP trunk migration, failover — critical for business continuity.

4. Porting Numbers & Ensuring PSTN/VoIP Continuity

• For companies relying on Skype Numbers or legacy PSTN/VoIP lines for customer calls — it’s essential to port those numbers to a new carrier or VoIP/SIP provider before shutdown.
• Services like number porting, new VoIP configuration, and integration with UC platforms must be planned ahead to avoid business disruption.

5. User Training, Change Management & Communication

• Migration involves human factors: training users on the new platform (features, UI, collaboration workflows), ensuring adoption, helping remote teams connect smoothly.
• Internal communications: informing staff, clients, stakeholders about the change, timelines, what works differently post-migration.
• Rollout of best practices: scheduling, meeting protocols, documentation, backup plans, security/compliance awareness.

6. Monitoring & Performance Review Post-Migration

• Once migrated, companies continuously monitor network performance (bandwidth usage, latency, call quality), user adoption, help-desk tickets, user feedback.
• They may plan for scalability: remote-work surges, distributed teams, increased video-call usage — ensure infrastructure scales without degradation.

Spenza’s Role: Connectivity as a Service (CaaS)

Forward-thinking enterprises are bypassing public internet dependencies entirely for their remote workforce. Spenza and similar enterprise connectivity providers offer solutions that treat connectivity as a managed service rather than a consumer utility.

The Enterprise eSIM Architecture:

1. Dedicated Business Connectivity: Spenza leverages eSIM technology to provision a secondary, business-dedicated cellular line on employee devices (laptops, tablets, smartphones), separating business traffic from personal home Wi-Fi usage.
2. Carrier-Agnostic Failover: Unlike single-carrier contracts, Spenza’s platform aggregates multiple networks. If one carrier’s signal is weak at an employee’s home, the device automatically switches to another provider with stronger signal, ensuring “always-on” reliability required for Teams Phone and video meetings.
3. Direct Cloud Peering: By utilizing cellular data, traffic bypasses congested local Wi-Fi and connects directly to carrier backbones, often with better peering to cloud providers like Microsoft Azure.

Why a Partner Like Spenza Matters — Connectivity, Reliability & Peace of Mind

Here’s why companies migrating from Skype — or legacy communication/VoIP systems — should seriously consider working with a connectivity/infrastructure partner like Spenza:

• Specialized expertise: Upgrading network circuits, configuring QoS, SIP-trunks/VoIP/PSTN bridging, number-porting are non-trivial tasks; many internal IT teams may not have that bandwidth or expertise.
• Infrastructure readiness: Spenza can help ensure circuits are enterprise-grade, scalable, redundant, and optimized for video/voice — avoiding common pitfalls like bandwidth shortage, jitter, downtime.
• Smooth migration with minimal disruption: With planning, pilot-runs, phased rollout and support, downtime and client/employee impact can be minimized.
  
• Long-term support and future-proofing: As business communication needs evolve (more remote work, heavier video use, global collaboration), having a robust, managed network ensures you’re ready — not scrambling.
• Value for money vs cost of failure: Migration may require upfront investment — but cost of poor communication, downtime, disrupted customer service or lost clients can be far higher.

Conclusion: Upgrade Your Communication Infrastructure Now

The retirement of Skype in May 2025 marks a major shift in business communication and a clear opportunity for companies to modernise. This transition is not just about switching to Teams or Zoom. It’s a chance to upgrade aging systems, improve network reliability, support hybrid work and build a future-ready communication strategy.

With careful planning and the right connectivity partner like Spenza, businesses can turn this change into a competitive advantage. Treat your move from Skype as a full infrastructure upgrade to gain long-term resilience, better performance and stronger productivity.

Spenza provides the modern VoIP connectivity and high-quality communication solutions needed to power today’s digital workplace. If you are exploring Skype alternatives or need reliable business VoIP, now is the time to upgrade.

FAQs

Is your network ready for October 2025? Contact Spenza today for a Connectivity Audit and seamless migration support.