If you are comparing Microsoft Teams with Skype for Business, the first thing worth knowing is that Microsoft has already made most of this decision for you.
Skype for Business Online was retired on 31 July 2021. Microsoft announced it two years in advance, then began decommissioning the underlying infrastructure from 30 June 2022. Since the retirement, users whose accounts live in the cloud cannot be set to anything other than TeamsOnly mode. There is no cloud version of Skype for Business left to choose.
That does not mean nobody is still running it, which is why this comparison is still worth making.
So what are you actually running?
Microsoft was explicit that the online retirement “does not affect support for on-premises deployments of Skype for Business Server and Lync Server 2013”. If Skype for Business is still working in your business today, it is almost certainly a server sitting in your own building.
Check which version. Skype for Business Server 2019 left mainstream support in January 2024, and extended support ended in October 2025. Anything older left support earlier. A Skype for Business Server running now is an unsupported, internet-adjacent server handling your calls and your presence data, and the Essential Eight is unambiguous that operating systems and software no longer supported by vendors should be replaced rather than kept.
So the real question is not “which is better”. It is “what do I move to, and what will I lose”.
What genuinely differs
Conversations persist. Skype for Business chat was a session. Close the window and it was effectively over. Teams conversations stay, are threaded, and are searchable months later. For a business that keeps records, that is the biggest practical change and the one that takes the most adjusting to.
Files live somewhere sensible. Teams puts files in SharePoint and OneDrive rather than sending them as attachments. Every team gets a site, every channel a folder. Microsoft’s documented storage for Business Basic and Business Standard is 1 TB per organisation plus 10 GB per licence purchased, with files up to 250 GB each. The advantage is not the capacity. It is that documents have one location, one version, and your retention and permissions settings apply to them.
Meetings run at a different scale. The same Microsoft page puts meetings at up to 300 people on Microsoft 365 Business Basic, Business Standard, Business Premium and Teams Essentials, rising to 1,000 on enterprise plans, with a 30-hour limit on meetings and events. Private chats hold up to 250 people. If you run large sessions, note that Teams live events retired on 30 June 2026, with events scheduled before that date supported through to 28 February 2027. Town halls and webinars replace them.
The channel model. This is the part Skype for Business never had. Work is organised by project or department rather than by who you happen to be messaging, so a new person joining a job can read what has already been decided rather than asking three people.
Calling works differently, and costs differently. Plenty of businesses used Skype for Business with an on-premises gateway for phone calls. Teams does the same job, but Microsoft’s Teams Phone documentation is clear that you need two separate things: a Teams Phone licence for the user, and at least one operator solution that supplies phone numbers and access to the public telephone network. Calls between your own staff are free either way. Calls to real phone numbers are a purchase. Budget for it before you decommission anything.
Security and device controls are in the same place. Because Teams sits inside Microsoft 365, the multi-factor authentication, conditional access and device management policies you apply to email apply to it too. With Skype for Business Server, those were separate systems with separate rules.
What you lose
Being honest about this makes the move easier, not harder.
You lose local control. A server in your building is one you can patch on your own schedule and keep running during an internet outage. Teams is a cloud service, so if the line is down, Teams is down. That is an argument for a decent secondary connection, not against the move, but it is a genuine change for businesses used to their phone system living onsite.
You lose the lighter client. Skype for Business was a small application that did chat, presence and calls. Teams does considerably more, and on older hardware you will feel that. If half your fleet is aged, work out the replacement plan before the migration rather than during it.
You also lose some habits. Persistent, threaded, channel-based conversation is genuinely better once people adjust, and genuinely confusing for the first fortnight. Plan for that fortnight.
What a move involves
Two details from Microsoft’s own retirement guidance are worth knowing because they cost people data.
Contacts move across when a user signs into Teams for the first time after being upgraded, not automatically in the background. Anyone who never signs in does not get their contact list. And meetings that were organised in Skype for Business need to be rescheduled as Teams meetings, or converted using the Meeting Migration Service, or they stop working once the old infrastructure is removed for that user.
For a business running its own server, the sequence is generally the same: confirm licensing, decide how phone numbers will reach Teams, pilot with a small group covering each role, migrate in waves, then keep the old system available read-only for a short period before decommissioning it. The part that takes the longest is never the software. It is the phone numbers.
What we actually see
In the twelve months to 18 August 2026 our service desk logged nine Teams tickets across five client businesses, and zero tickets mentioning Skype for Business. Not one.
That is the most honest comparison available. It is not that Skype for Business is running perfectly somewhere. It is that almost nobody is running it any more, and the small number of businesses that are tend not to raise tickets about it until something stops working entirely.
If Skype for Business is still in your building, the step for this week is to find out which version of the server it is and when its support ended. That single fact decides how urgent the rest of it is.
If you want a second opinion on what a move would involve, including the phone side, get in touch.