With only four months to go until the planned retirement of Skype for Business Online on July 31, 2021, we predictably enter the season of Fear, Uncertainty and Doubt with misinformation flying in all directions about what exactly is going to change, and what impact this will have for customers using Skype for Business today. Many organisations are now starting a hurried migration to Microsoft Teams, which Microsoft has previously stated (as early as 2018) will become the hub for teamwork and collaboration within the Microsoft 365 productivity stack

But is there any actual urgency? Will your organisation be in a pickle if you don’t finish rolling out Teams before July 31? Let’s find out by examining the top questions and some of the myths that many organisations are asking:

Myth #1: Skype for Business Online is being completely shut down on July 31, 2021.

Reality: Not true

Skype for Business Online isn’t going anywhere soon, as you will see from some of the further points below. What is happening on July 31 has much more to do with the Teams co-existence mode than anything being “shut down”. For those not familiar with this, it’s the per-user (and global) setting that Microsoft make available so that you can control (to an extent) how Skype for Business and Teams play together while you’re transitioning from one to the other, and there are five options:


Skype only mode
As the name suggests, this mode effectively disables the Teams client entirely, and all Chat, Calling and Meetings are received in Skype for Business.
Skype for Business with Teams Collaboration mode Unlike Skype only mode, this unlocks the Teams client for collaboration (Teams and Channel-based chat) and co-authoring – but Chat, Calling and Meetings are still disabled in Teams, and route to Skype for Business
Skype for Business with Teams Collaboration and Meetings mode(also known as Meetings First) Similar to Skype for Business with Teams Collaboration mode, but with Meetings defaulting to Teams instead of Skype for Business.  For example, the New Online Meeting button in Outlook creates a Teams meeting instead of a Skype meeting.  Chat and Calling are still disabled in Teams, and route to Skype for Business
Islands mode This is the default co-existence mode, and therefore the most common.  Both Skype and Teams clients are fully enabled and allow users to access all features and workloads in either platform.  Incoming PSTN phone calls however, will still route to Skype for Business only.
Teams only mode This of course is the endgame Microsoft are steering customers towards in the long term – in this mode the Skype for Business client is effectively disabled, and all Chat, Calling and Meetings route to Teams.  This is also the only mode in which your incoming PSTN phone calls will route to Teams.


So, what then is happening on July 31? Effectively, the co-existence mode for all users homed in Skype for Business Online will be changed to Teams only mode, and you won’t be able to change it back. So, the net effect for end-users who are enabled for Skype for Business Online, is that they will switch from Skype for Business to Teams as part of this change. It’s likely this will also impact Meeting Room Systems or Common Area Phones homed in Skype for Business Online – although any Skype for Business IP phones will continue to work via the 3PIP gateway (more about that further down).

It’s important to understand that this won’t affect users homed in Skype for Business Server 2015 / 2019 on-premises (nor any previous version of the product, such as Lync Server). The co-existence mode for any users with a Directory Sync status of “on-premises” will not be changed, and these users can continue to operate in Islands mode, or any of the other Skype for Business co-existence modes.

Myth #2: Chat between Skype for Business on-premises and Teams will stop working.

Reality: Not true

This myth says that any communication between Teams and Skype for Business on-premises happens via the Skype for Business Online gateway, so when this gets “shut down” on July 31, Teams users and Skype for Business on-prem uses won’t be able to talk to each other. Well as above, nothing is being “shut down”, and there is no plan to impact any customers who continue to run Skype for Business on-premises. Indeed Microsoft announced that the next version of Skype for Business Server on-premises “vNext” will launch later this year with (presumably) the standard 10-year lifecycle for on-prem server products, so it would be ludicrous to think that these deployments would not be able to communicate and collaborate with users on the Teams platform after July 31.

Myth #3: You won’t be able to migrate users from Skype for Business on-premises to Teams after July 31, 2021.

Reality: Not true

It’s true that when a user is moved from Skype for Business Server on-premises to Teams, they will use the Skype for Business Online service to transition from Skype for Business on-premises to Teams only mode in the Teams cloud service. However, this myth says that once Skype for Business Online gets “shut down” on July 31, these migrations will no longer be possible [so you better get it done before then!]

For the same reasons as above, this is plainly ridiculous. Yet we continue to hear this misinformation being spread around. Given that Microsoft’s long-term goal is to move all Skype for Business customers onto the Teams cloud service, why would they do anything to make this more difficult on, or any time after, July 31st? The reality is that the Skype for Business Online platform will continue to exist for many years to come, in the form of “Skype for Business Online Services” – while this won’t allow users or devices to continue to use Skype for Business directly, it will continue to provide all of the interoperability between Skype on-prem and Teams, including the ability to migrate users from on-premises to the cloud, exactly the same way it works today.

Myth #4: All your Skype for Business phones will stop working after July 31, 2021.

Reality: Not true

Ok, this is starting to sound like Y2K all over again. So full credit to Microsoft on this one, who from Day 1 of the announcement that Teams will eventually replace Skype for Business, has made it abundantly clear that any IP phones purchased for Skype for Business will continue to work with Teams (at least until July 2023).

How will this work? Via something Microsoft is calling the 3PIP gateway which (you guessed it) is a stripped down version of Skype for Business Online, which will only accept client registrations from certified Skype for Business IP phones, and marry them up with a user configured in Teams only mode as above. Microsoft is giving us an additional 2-year buffer (until July 31, 2023) to continue to use our Skype for Business IP phones with Microsoft Teams until this service becomes unavailable. After that, you’ll need to plan to replace those phones with native Teams phones, or alternatively move to the recently announced SIP gateway, and switch your phone firmware to a generic “SIP mode”.

What will this look like to the end-user? There won’t be any change to the user interface on the Skype for Business phone, as it continues to register to the cloud as a Skype for Business endpoint. You will also miss out on all Teams-specific features, such as one-touch join to scheduled Teams meetings, starting ad-hoc Teams meetings, and some features when the user is an agent within a Teams Call Queue (hunt group). It’s also unclear to what extent integrated Skype features (such as Directory Search) will continue to work after users are moved into Teams only mode.

Some phones and meeting room devices (such as the Poly Trio and some models from Yealink) are essentially both Skype for Business and Teams phones, and are simply a firmware replacement away from switching from one to the other, giving you a full native audio experience with access to the full feature set on either platform. That’s not what the 3PIP gateway is for – if you’re in this scenario, you should plan to roll out the Teams firmware replacement to your phones in conjunction with your migration to Teams to give users the full / native Teams experience. The 3PIP gateway is specifically for Skype for Business IP phones that can’t be upgraded to Teams phones.

Note also that the 3PIP gateway service is a (free) voice-only service geared towards compatibility of IP phones, not Skype for Business meeting room devices. If you want to hang on to your Skype for Business Meeting Room Systems (SRS) that can’t be upgraded to Microsoft Teams Room Systems (MTR) for a bit longer, you can achieve this by signing up for one of the Cloud Video Interop (CVI) service providers that Microsoft have partnered with, which will allow a Skype for Business Room System to join a Microsoft Teams meeting. However, the usual feature limitations will apply – some Teams features (such as participant controls) won’t work when joining from a non-Teams room system.

Myth #5: Microsoft are making my life harder for no reason

Reality: Not true (but it might feel like that in the short term!)

The reality is that use cases and requirements have outgrown what the Skype for Business platform (as an evolution of Lync, and OCS / LCS before that) can provide. Specifically, virtual team-based collaboration via technology is more important than ever in the current remote working climate, and a much wider slice of the workforce need the ability to easily share and co-author work within the same tool as casual chat or team-based conversations (think Slack). Switching between Skype for Business and SharePoint chat was a pain even for the hardcore Information Worker, and just wasn’t going to cut it for a non-technical user.

Also meetings needed to be more powerful, with the ability to view everyone in the meeting at the same time (think Zoom), not just the most recent 4 or 5 speakers. In addition, new features like live transcription, multi-language translation and breakout rooms are again being used by a much broader slice of the workforce and need to be available to all, and recordings of these meetings need to be easier to share and view after the fact – and all of this points to a new collaboration platform drawing from the power of the cloud!

Tech tip: To be more specific, Microsoft Teams is designed as a decentralised service using Anycast IP Addressing, unlike Skype for Business where everything had to run through a singular point. Teams was designed from the ground up to be cloud-centric, whereas Skype for Business Online was still very much a legacy on-premises server product, that was retroactively re-designed to run in the cloud. For more information, have a read of Is deploying Office365 Multi-Geo really needed for Voice in Australia? - UcMadScientist.com.


So if you’re currently running Skype for Business on-premises, and not yet thinking seriously about the move to Microsoft Teams, it’s probably worth starting to plan for; but fear not with respect to the changes on July 31, as it won’t impact your ability to migrate from Skype for Business Server on-premises after this date.

Microsoft will continue to focus their new development effort and feature release on the Teams platform, and eliminate the duplication provided within Skype for Business. For many organisations, this will result in a significant amount of short-term user angst and management of change, not to mention costs associated with replacing any devices or meeting rooms that were purchased for the Skype for Business rollout. In the long term however, Teams fits well into Microsoft’s cloud-first vision of rapid and low-impact updates and feature development, and should provide organisations with a much more stable roadmap for teamwork, communications and collaboration moving forward.