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What Is Skype VoIP and Who Is It For?
Errin O\'Connor
8 min read
Skype VoIP (Voice over Internet Protocol) is Microsoft's consumer and small business voice calling service that transmits phone calls over the internet instead of traditional telephone lines. While Skype pioneered mainstream VoIP adoption when it launched in 2003, Microsoft has officially retired Skype as of May 2025 and migrated all users to Microsoft Teams. For enterprise organizations, this transition is significant: if your business still relies on Skype for any voice communications, the time to migrate to Microsoft Teams is now. At EPC Group, we have guided hundreds of organizations through Skype-to-Teams migrations, ensuring zero disruption to business communications.
How Skype VoIP Technology Worked
Understanding Skype's VoIP technology provides context for why Microsoft Teams is a superior successor and what capabilities to expect from modern VoIP:
- Peer-to-peer architecture (original) -- Skype originally used a peer-to-peer network where calls were routed through other Skype users' computers. This reduced infrastructure costs but created quality inconsistencies.
- Cloud-based architecture (later) -- Microsoft migrated Skype to cloud-based supernodes hosted in Microsoft data centers, improving reliability and call quality significantly.
- Codec technology -- Skype used the SILK codec (developed by Skype) for voice and VP8 for video, providing high-quality audio at relatively low bandwidth (6-40 kbps for voice).
- PSTN gateway -- Skype's "Skype Out" and later "Skype Credit" services connected VoIP calls to the traditional phone network, allowing Skype users to call landlines and mobile phones worldwide at reduced rates.
Who Used Skype VoIP?
Skype served several distinct user segments before its retirement:
- Consumer users -- Individuals and families using Skype for free voice and video calls to other Skype users, popular for international calling to friends and family.
- Small businesses -- Companies that used Skype as an informal conferencing and calling tool before adopting enterprise-grade solutions. Skype for Business (the enterprise product) was a separate application.
- Remote workers and freelancers -- Before Zoom and Teams, Skype was the default tool for remote meetings, client calls, and virtual interviews.
- International businesses -- Organizations with global operations used Skype Credit to make affordable international calls, bypassing expensive traditional carrier rates.
The Transition to Microsoft Teams
Microsoft has consolidated all its communication tools into Microsoft Teams:
- Skype consumer retired (May 2025) -- Microsoft officially shut down Skype consumer in May 2025. All contacts, chat history, and Skype Credit balances were migrated to Microsoft Teams (free version) for consumer users.
- Skype for Business Online retired (July 2021) -- The enterprise version of Skype was retired in 2021, with all enterprise users migrated to Microsoft Teams. On-premises Skype for Business Server continues to receive extended support but no new features.
- Microsoft Teams: The successor -- Teams provides everything Skype offered plus significantly more: persistent chat, channel-based collaboration, file sharing, app integration, enterprise phone system (Teams Phone), meeting rooms, and AI-powered features (Copilot, live captions, meeting recaps).
Microsoft Teams VoIP vs. Skype VoIP
| Capability | Skype VoIP | Microsoft Teams |
|---|---|---|
| VoIP calling | Skype-to-Skype free | Teams-to-Teams free, plus PSTN options |
| External PSTN calling | Skype Credit (pay-as-you-go) | Calling Plans, Direct Routing, Operator Connect |
| Enterprise phone system | Not available in consumer Skype | Full PBX replacement with auto-attendants and queues |
| Meeting capacity | Up to 100 participants | Up to 1,000 (10,000 with Town Hall) |
| Security | Basic encryption | Enterprise-grade (MFA, DLP, compliance recording) |
| AI features | None | Copilot, live captions, transcription, meeting recap |
Migration Planning for Remaining Skype Users
If your organization still has users on Skype (consumer or Skype for Business Server on-premises), here is what you need to plan:
- Inventory current usage -- Document all Skype users, their calling patterns (internal, external, international), any Skype credit balances, and integrations with other systems.
- License planning -- Determine which Microsoft 365 licenses are needed. Teams is included in Microsoft 365 Business Basic, E3, and E5. Teams Phone requires an add-on license unless you have E5.
- User training -- While Teams shares some UX patterns with Skype, the expanded feature set requires training. Focus on calling, meetings, chat, and channel collaboration workflows.
- Contact migration -- Skype contacts can be migrated to Teams. For Skype for Business Server, Microsoft provides coexistence modes during the transition period.
Why EPC Group for Skype-to-Teams Migration
- Hundreds of migrations completed -- We have migrated organizations from Skype for Business (both Online and Server) to Microsoft Teams with zero downtime and full feature parity.
- Coexistence expertise -- For complex migrations, we configure Teams/Skype coexistence modes that allow a phased transition while maintaining communication between both platforms.
- PSTN connectivity -- We design and deploy the right PSTN solution (Calling Plans, Direct Routing, or Operator Connect) based on your calling patterns, geographic footprint, and budget.
- Change management -- We provide user training, adoption campaigns, and champion programs to ensure your organization actually uses Teams effectively, not just installs it.
Still on Skype? Time to Migrate to Teams.
With Skype officially retired, EPC Group can fast-track your migration to Microsoft Teams with full VoIP, PSTN connectivity, and enterprise collaboration features. Contact us for a migration assessment.
Frequently Asked Questions
Is Skype still available?
No. Microsoft retired Skype consumer in May 2025. The application is no longer available for download, and existing installations redirect users to Microsoft Teams (free). Skype for Business Online was retired in July 2021. Skype for Business Server on-premises is still under extended support but receives no new features and should be migrated to Teams as part of your modernization strategy.
What happened to my Skype contacts and chat history?
Microsoft migrated Skype contacts to Microsoft Teams during the retirement process. Chat history from Skype was available for export before the shutdown deadline. For Skype for Business users, conversation history was migrated to Teams as part of the Teams Upgrade process. If you missed the migration window, contact Microsoft support for data recovery options.
Is Microsoft Teams free like Skype was?
Microsoft Teams has a free version that provides basic chat, video calling (up to 60 minutes per meeting), and file sharing -- similar to what Skype offered for free. For enterprise features (unlimited meetings, Teams Phone, compliance tools, advanced security), you need a paid Microsoft 365 license starting at $6/user/month for Business Basic.
Can Teams make phone calls to regular phone numbers like Skype could?
Yes. Microsoft Teams supports PSTN calling to landlines and mobile phones through Microsoft Calling Plans, Direct Routing, or Operator Connect. Unlike Skype Credit (pay-per-minute), Teams offers structured calling plans with included minutes or unlimited calling. Teams Phone also provides full PBX features (auto-attendants, call queues, voicemail) that Skype never offered for consumers.
How long does a Skype to Teams migration take?
For consumer Skype users transitioning to Teams free, the migration is instantaneous -- just download Teams and sign in with your Microsoft account. For enterprises migrating from Skype for Business Server to Teams, a typical migration takes 3-6 months depending on the number of users, PSTN requirements, and custom integrations. EPC Group has completed accelerated migrations in as little as 4 weeks for organizations that need to move quickly.