Skip to content
1300 881 641

Telstra Calling for Office 365 - TCO 365

Enterprise Voice Solution

Telstra and Microsoft partner together for a world-first PSTN calling solution. Here's everything you’ve ever wanted to know about Telstra Calling for Office 365 (or TCO365), from features and benefits to use cases and pricing – all in one place.

What is TCO365?

Or, What is Telstra Calling for Office 365?

In a world-first offering, Telstra Calling for Office 365 is a solution offered by Telstra to allow Australian consumers to access cloud-based PSTN calling plans in conjunction with their Microsoft Office 365 account.

Previously, this was done by deploying a potentially costly Cloud Connector Edition (CCE) solution, or an on-premise server.  In other countries, access to PSTN calling with Microsoft is done very differently to how it’s done here in Australia.

The primary platform the users then use to make their phone calls is Microsoft Teams, though some organisations may opt for a hybrid deployment with Skype For Business until S4B is end of life.*  (Best practice is to transition fully to Microsoft Teams, as the feature-rich platform allows for true collaboration.)

The goal is to bring your users to a single app for a rich user experience, whilst also being fiscally responsible: your organisation is likely already paying for Microsoft 365 Enterprise licensing, so why not take advantage of all the tools that are at your disposal?  Consolidation of costs for PABX systems and maintenance, calling rates, chat applications and other collaboration platforms, file storage, security, BI, etc, ensures that you’re not over-paying, and getting a real return on investment for the technology stack you have.


Skype for Business Online has an end of life date of 31 July 2021.  Skype for Business 2019 will remain supported until 14 Oct 2025. 

Telstra's Announcement Video

Play Video

TCO365 Features

What makes Telstra Calling for Office 365 so great? The features available with TCO365 are there to make your life oh-so-easy, both as an end user, and as an IT Administrator.


Work from anywhere, anytime – true flexible working

No one could have predicted 2020 would have gone the way did (except maybe the Simpsons), but organisations who had already switched (or were in the process of switching) to Microsoft Teams didn’t break a sweat when the lockdowns came. Home or office, it didn’t matter. Give your Teams deployment an upgrade by moving your calling plans to TCO365.

Full voice functions* with built-in audio and video conferencing

You can still have traditional call handling functions like hold, transfer, forwarding and voicemail in the cloud, with the added bonus of audio and video conferencing, and so much more. With the addition of other integrations, you can also expand to have your call centre capabilities integrated into the system.

Truly Unified Communications – One Source of Truth

Telstra Calling for Microsoft Office 365 brings together your key business tools under a single business number. Consolidate and strengthen your organisation’s technology stack and enable your organisation to be more effective in their daily workflows due to a centralised workspace, cloud data and file storage, and a cohesive user experience across familiar tools.

Enterprise-grade Security

Take full advantage of Microsoft’s security and compliance by more expansively using the Microsoft licencing you’re already paying for.

Connect your teams more effectively

See who’s available and contact them on the most appropriate channel: voice, video calling or chat. Reduce clutter in your inbox and make communication more efficient.

Present a professional image

One business number lets you make and receive calls whether in the office or on the road. Remote and firstline workers no longer need to rely on giving out their personal mobile, or carrying two phones with them all the time for their privacy. In addition, a full-featured meeting and calling platform ensures smooth meetings with external stakeholders as well as internal.

Ability to access growth funds

If you are a Telstra Managed Customer, you may qualify to access funding for your deployment, or a TCO365 Pilot. Give us a call and we can help discover if you qualify.

Easy to Administrate

Your VOIP solution will now be managed through your Office 365 Admin Portal – making your IT admin tasks easier to carry out.

Calling – Simplified

Local calls? Long distance calls? Video conference calls? Mobile calls? Make and receive all types of calls under the single business number.

TCO365 Benefits

Or, Why Choose Telstra Calling for Office 365?

A true unified collaboration experience, with mixed mediums of communication

Having all (or the majority of) your workflows and technology integrated into one platform is true definition of unified communications. This will allow your teams to communicate in more than just text and collaborate in real time. When you add human elements such as voice and video, communication and collaboration become richer and more efficient.

Simplify billing and budgeting

Still under an existing Telstra contract? Continue using your current negotiated calling rates with Telstra Calling for Office 365. Billed through your Telstra bill, TCO365 enables you to streamline outgoing communications expenses. Instead of paying for conferencing, call recording, voice, chat software, Office 365, etc, pay for your unified communications solution all on one bill.

The best of both worlds = Carrier Plus Technology

Co-created by Telstra and Microsoft – both are market leaders in innovation. Work with a Partner who is Gold Certified by both to make sure you get the most experience and knowledge to help you.

Relatively simple in comparison to other options

Deploy, manage and scale with ease. Work with a preferred TCO365 Partner to ensure that your team is fully supported throughout the process of the initial deployment.

How Does TCO365 Work?


Telstra Calling for Office 365 makes calling simple. Telstra provides the link to allow you to bring all voice calling directly into the Office 365 cloud.

Previously, organisations had to set up expensive and non-scalable hard-wired infrastructure and equipment on-premises to deliver their voice calling solution. Now, with nothing more than adequate internet access, a laptop, and a certified headset or speakerphone, members of your organisation can have their full-featured voice calling, audio and video conferencing, and all collaboration tools at their fingertips, anywhere and anytime.


How It Works

At a basic level, the administration of TCO365 is as simple as the administration of Office 365. Users are allocated their phone number in the Office 365 Admin Portal. Organisations can choose to use their existing numbers and port/migrate them into Office 365 or choose and allocate new numbers. As your organisation grows, it is simply part of allocating the new member their Office 365 licence to get them set up with their new number.

You need to ensure you have the right Microsoft 365 licence to enable TCO365, and yes, you do need to have a current Microsoft 365 subscription. In addition, the organisation must have at least 20 users.

Skype or Teams?

Skype for Business Online vs Skype for Business On-Premise vs Microsoft Teams?

There are pros and cons to all three of Microsoft’s current calling solutions. It comes down to assessing your organisation’s requirements, and your IT strategy moving forward. From there, it comes down to a process of elimination.



It is important to note that you cannot access Telstra Calling for Office 365 using Skype for Business On-Premise. You can absolutely have access to Microsoft Teams and all its collaborative functions, but the PSTN calling functionality (the ability to dial external numbers) within the platform relies on the cloud capabilities. Therefore, porting of existing telephone numbers can only be done if the users are “homed online.”

In addition, the deployment of a Skype for Business Server (as well as the redundancies and maintenance needed to ensure reliable connectivity) is a costly endeavour, and not a small project. For the majority of organisations still using a traditional PABX phone system, it would be wiser to transition straight to a cloud-based solution. Customers on OCS or Lync would be the only ones who would be well-served by transitioning to Skype for Business 2019 on-premise as part of their journey.

Essentially then, the question is “Skype for Business Online or Microsoft Teams,” as a Skype for Business On-Premise deployment will not work with Telstra Calling for Office 365.

Skype or Teams: Compare the Pair


  • End Date
  • Video Calling/Conferencing
  • Audio Calling/Conferencing
  • Meeting Recording
    Meeting Participant Limit
  • Persistent Chat
  • Team-based Chat
    Document Sharing
  • Collaboration (white boarding, shared folders, project management integration, 3rd party tool integration, etc)
  • Bot Integration

Microsoft Teams

  • End DateNone
  • Video Calling/ConferencingYes
  • Audio Calling/ConferencingYes
  • Meeting RecordingYes
    Meeting Participant Limit
    300 in a regular meeting, 10,000 using Microsoft Teams Live Events
  • Persistent ChatYes
  • Team-based ChatYes
    Document Sharing
    Yes - share live documents that can be edited in real time, simulataneously
  • Collaboration (white boarding, shared folders, project management integration, 3rd party tool integration, etc)Yes
  • Bot IntegrationYes

Skype For Business

  • End DateS4B Online: 31 Jul 2021
    S4B 2019: 14 Oct 2025
  • Video Calling/ConferencingYes
  • Audio Calling/ConferencingYes
  • Meeting RecordingYes
    Meeting Participant Limit
  • Persistent ChatNo
  • Team-based ChatNo
    Document Sharing
    Sort of (you must share from OneDrive, SharePoint, or a copy of a document)
  • Collaboration (white boarding, shared folders, project management integration, 3rd party tool integration, etc)No
  • Bot IntegrationNo

Skype for Business Online, as stated above, has an end of life date of 31 July 2021.  If you are not yet on Skype for Business, it would not make sense to make the investment to go from, for example, a PABX phone system, to Skype for Business Online, when you will have to switch to Microsoft Teams anyway mid-2021.


Telstra Calling for Office 365 (or TCO365 for short) is a cloud-based VoIP calling solution, using Microsoft Teams as the calling platform, and Telstra as the hosting carrier.

Check out our new meeting rooms!

Book Now