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Summit Internet
Telstra Calling for Office 365 customers

Telstra Calling for Office 365 Ends 30 November 2026. Keep Teams. Keep Your Numbers.

Telstra is withdrawing Telstra Calling for Office 365 (TCO365). Summit's dedicated migration team moves your Teams calling onto our own voice network, or onto a Summit hosted phone system, and ports the local numbers on your Telstra service free of charge. Start today: a number can only be ported while its service is still active.

Claim Free Number Porting Call 1300 049 749

One-time offer for Telstra customers

Free local number porting when you move your Telstra Calling for Office 365 service

Step 1 of 2: your details
Which Telstra service do you have? *

Offer: free porting of local (geographic) numbers attached to your Telstra service when you move to a Summit voice plan. 1300, 1800 and 13 numbers excluded. Expires 30 August 2027 unless extended.

Would rather talk? Call 1300 049 749

Overview

If your staff make and take calls in Microsoft Teams through Telstra Calling for Office 365, your calling service has a hard end date. Telstra's customer terms state that TCO365 has not been sold to new customers since 1 November 2024, that existing customers have not been able to add services, make changes or recontract since 30 August 2026, and that on and from 30 November 2026, TCO365 "will be withdrawn from the market and no longer be provided to customers, unless otherwise notified by Telstra".

Telstra Calling for Office 365 Date
No longer sold to new customers 1 November 2024
No new services, changes or recontracts 30 August 2026
Withdrawn, no longer provided 30 November 2026

That leaves weeks, not months. The good news is that Microsoft Teams itself is not going anywhere. TCO365 is only the calling layer: the PSTN connection, the phone numbers and the calling plan licence that let your Teams users dial out and receive calls. Replace that layer and your staff keep working in exactly the same Teams app, with the same numbers.

Summit is an ACMA licensed carrier (Carrier Licence #388) with its own voice network. We connect that network to your Microsoft tenant, port your numbers across and reassign them to your users, auto attendants and call queues. If you would rather step away from Teams for calling, we can move you to a Summit hosted phone system instead.

Time matters because of how porting works. The ACMA is clear that only active numbers can be ported, and a port involving several numbers can take up to 30 days. Nobody can promise a port will complete before 30 November, which is exactly why the request needs to be lodged now, while your TCO365 service is still running.

Summit Internet is an independent Australian carrier and is not affiliated with Telstra or Microsoft. For details of your own service, check your Telstra account or contact Telstra.

Key Benefits

  • Keep Microsoft Teams, Change Only the Calling

    Your staff keep the Teams client they use every day on desktop and mobile. Summit replaces the calling service behind it, so there is no new app to learn, no retraining and no second phone on the desk unless you want one.

  • Free Local Number Porting

    Move your Telstra Calling for Office 365 service to a Summit voice plan and we port the local numbers attached to your Telstra service with no porting fee. Your direct dials, main number and auto attendant numbers stay exactly as your customers know them. A one-time offer for Telstra customers, available until 30 August 2027 unless extended.

  • A Dedicated Migration Team, Starting Today

    Your move is run by Summit's dedicated migration team, not a general sales queue. With the withdrawal date this close, they start with the step that takes longest: getting your port request lodged correctly the first time.

  • Keep Your Microsoft Licences Where They Are

    TCO365 required your Microsoft licences to be bought through Telstra. Summit does not resell Microsoft licensing, so we are not asking you to move it. Keep your licences with your current provider; we supply the carrier side. If you choose to move your licensing elsewhere later, that is your decision, not a condition of ours.

  • Calls on a Network We Own

    Your Teams calls ride Summit's own voice network rather than being handed between wholesalers. When something needs fixing, the people you call are looking at infrastructure we build, own and run.

  • Emergency Calling Handled Properly

    As a licensed carrier we carry the regulatory obligations for emergency calling. Calls to 000 from your Teams users are routed with the registered service address, and we walk you through keeping those addresses current as staff move around.

  • Prefer a Phone System Instead?

    Not every business wants calling inside Teams. Summit hosted PBX gives you desk phones, cordless handsets, softphone apps, auto attendant and call queues in one per-user price, with your local numbers ported across under the same offer.

  • Pay for Capacity, Not Per Head

    With Summit as your Teams carrier you pay for call capacity rather than a calling plan for every user. For businesses with a mix of heavy and occasional phone users, that usually works out cheaper.

What Changes in Your Microsoft Tenant

Leaving TCO365 is not just a number port. Several parts of your Teams set-up point at Telstra and need to be moved in the right order. Here is what each part becomes with Summit.

On Telstra Calling for Office 365 With Summit
TCO365 calling plan licence assigned to each user Summit voice routing to your tenant, no per-user calling plan
Telstra PSTN numbers assigned to users The same local numbers, ported to Summit and reassigned
Numbers on auto attendant and call queue resource accounts Reassigned to the same resource accounts at cutover
Prerequisite Teams Phone licences bought through Telstra Kept with your existing licence provider
Telstra's delegated admin access to your tenant Removed after cutover, once you no longer need Telstra support
Telstra fault helpdesk Summit support, on a network we own

Telstra's terms also set two porting rules worth knowing up front: the numbers you port out must go at the same time, and they cannot be ported in blocks of fewer than 100 contiguous numbers. Numbers also have to be unassigned in the Teams admin centre at the moment of cutover. Our migration team plans all of this with you so the port is not rejected and your users are not left without a number.

How It Works

  1. 1 Submit your enquiry

    Fill in the form above or call 1300 049 749. Tell us how many staff take calls in Teams and which numbers you want to keep. A recent Telstra bill speeds everything up.

  2. 2 Our dedicated migration team calls you

    A specialist calls to discuss your requirements: your Microsoft licensing, the numbers on your Telstra service, and your auto attendants, call queues and any Teams phones or common area phones.

  3. 3 Choose Teams Calling or a hosted phone system

    Stay in Microsoft Teams with Summit as your carrier, or move to Summit hosted PBX. Select how many physical handsets you need, or go softphone only.

  4. 4 We lodge your port and set up the new service

    We submit the port request straight away while your TCO365 service is still active, connect Summit to your Microsoft tenant, and preconfigure and ship any handsets you have chosen.

  5. 5 Migration support through cutover

    On cutover day your dedicated team works with you to unassign the Telstra numbers, reassign them on Summit, and test inbound and outbound calls, auto attendants and queues. Only then do we help you cancel with Telstra and remove its admin access. Do not cancel first: a disconnected number can no longer be ported.

Features

What Summit Provides

Carrier connection to your tenant
: Summit's voice network connected to your Microsoft 365 tenant for inbound and outbound calling in Teams.
Free local number porting
: The local numbers attached to your Telstra service ported with no porting fee.
New numbers if you need them
: Local numbers in every capital city, plus 1300 and 1800 numbers.
Emergency calling
: 000 calls routed with the registered service address for each user.
Australian support
: A carrier you can telephone, with your own migration specialist through cutover.

What Your Migration Team Handles

Licence check
: We review what your tenant already has and tell you plainly whether you need to add anything.
Porting plan
: Port request prepared against your Telstra account details and Telstra's block porting rules, lodged straight away.
Number reassignment
: Users, auto attendants and call queues reassigned to their numbers at cutover.
Cutover testing
: Inbound, outbound, transfers, voicemail, auto attendants and queues tested with you on the day.
Telstra exit guidance
: What to cancel, when, and when to remove Telstra's admin access.

If You Choose Summit Hosted PBX Instead

Handsets or softphone only
: Desk phones, cordless DECT handsets, or apps on mobile and computer.
Preconfigured hardware
: Handsets shipped ready to plug in, with extensions, auto attendant and ring groups set up.
Every feature included
: Auto attendant, call queues, ring groups, voicemail to email and call recording in one per-user price.

Microsoft Teams Calling or Hosted PBX?

Most Telstra Calling for Office 365 customers will stay in Teams, and that is usually the right call. But if Teams calling never quite suited your reception or your floor staff, this is the moment to change.

Summit Microsoft Teams Calling

Best for
Office teams that already live in Microsoft 365 and want calling inside Teams.
How it works
Summit connects its voice network to your tenant; staff keep calling from the Teams app.
Licensing
Requires a Microsoft licence that includes Teams Phone, which TCO365 already required, so most businesses have it.
Good to know
Auto attendants and call queues stay in your Microsoft tenant, under your control.

Summit Hosted PBX

Best for
Reception desks, shops, clinics and staff who answer calls on a handset.
How it works
A complete cloud phone system with handsets, softphone apps, auto attendant and queues.
Pricing
From $15 per user per month, every feature included.
Good to know
No Microsoft calling licences needed; works alongside Teams for meetings and chat.
See Summit Hosted PBX

Not sure? Your migration specialist will recommend one based on how your business actually takes calls.

Call 1300 049 749

Use Cases

  • The Accounting Firm With Twenty Teams Users

    A firm moved its phones into Teams through Telstra years ago and now has twenty direct dials, a main number on an auto attendant and a reception call queue. Summit lodges the port immediately, connects to the firm's tenant, and on cutover day reassigns every direct dial and both resource accounts, with the firm's Microsoft licensing left exactly where it was.

    Lawyers & Accountants

  • The Medical Practice That Needs Handsets

    A clinic used Teams calling on laptops, but reception never liked answering through an app. The practice moves to Summit hosted PBX with cordless handsets for reception, keeps Teams for meetings and chat, and has its local numbers ported free.

    Dentists & GPs

  • The Multi-Site Business With a Number Block

    A business with offices in two states holds a block of 100 numbers on TCO365. Because Telstra's terms require those numbers to port together, the migration team plans a single cutover across both offices and reassigns the whole block in one window.

Your situation not on this list? Tell us what you run or call 1300 049 749 and we will tell you honestly whether we can help.

Talk to an expert

Telstra Calling for Office 365 ends on 30 November 2026

A number can only be ported while its service is active. Send us your details today and our dedicated migration team will start your port straight away, with your local numbers moved free.

Claim free number porting Call 1300 049 749

Why Choose Summit

  • 01

    A Licensed Carrier, Not a Reseller

    Summit holds ACMA Carrier Licence #388 and operates its own voice network. Your Teams calls are on infrastructure we run and can fix.

  • 02

    We Do Not Sell You Microsoft Licences

    Because we do not resell Microsoft licensing, we have no reason to tell you to buy more of it. We tell you what your tenant needs and leave the rest alone.

  • 03

    Moving Businesses Off Closing Services Since 2000

    ISDN and PSTN shutdowns, the nbn rollout, providers leaving the market: Summit has moved businesses off retiring services for over two decades. A withdrawal date is a project with a deadline, and we run it like one.

  • 04

    One Team From Enquiry to Cutover

    The specialist who checks your licensing and lodges your port is the one who runs your cutover. Nothing is lost in a handover.

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Why Australian Businesses Choose Summit Internet

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    5 months ago

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    6 months ago

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Frequently asked questions

When does Telstra Calling for Office 365 end?
Telstra's customer terms state that on and from 30 November 2026, Telstra Calling for Office 365 (TCO365) will be withdrawn from the market and no longer provided to customers, unless otherwise notified by Telstra. Existing customers have not been able to add services, make changes or recontract since 30 August 2026.
What is Telstra Calling for Office 365 (TCO365)?
It is a Telstra calling service for Microsoft 365. Telstra supplies the connection between your Microsoft tenant and the phone network, the phone numbers and a calling plan licence assigned to each Teams user, so staff can make and receive ordinary phone calls in Teams.
Do I lose Microsoft Teams when TCO365 ends?
No. Only the calling service is being withdrawn. Teams chat, meetings and files are unaffected. What you need to replace is the calling layer that connects Teams to the phone network, which is what Summit provides.
Can I keep my phone numbers?
Yes, as long as they are ported while your TCO365 service is still active. The ACMA states that only active numbers can be ported. Under this offer, Summit ports the local numbers attached to your Telstra service free of charge.
Will my port finish before 30 November 2026?
We cannot promise that, and you should be wary of anyone who does. The ACMA says ports involving more than one local number can take up to 30 days. What we can do is lodge your port request immediately and correctly, which is the single biggest factor you control. Contact us today rather than next week.
Should I cancel Telstra Calling for Office 365 first?
No. Cancelling can disconnect your numbers, and a disconnected number cannot be ported. Keep the service running, let us port the numbers, then cancel with Telstra once your calls are working on Summit.
Do I have to move my Microsoft licences away from Telstra?
Not for Summit. TCO365 required your prerequisite Microsoft licences to be bought through Telstra, but Summit does not resell Microsoft licensing and does not need you to move it. Keep your licences with your current provider; we connect the calling. You do need a licence that includes Teams Phone, and we will check your tenant before quoting.
Can I port just some of my numbers?
Telstra's terms for TCO365 say the numbers you want ported out must be ported at the same time, and cannot be ported in blocks of fewer than 100 contiguous numbers. If you hold a number block, our migration team will plan the port around that rule.
What happens to my auto attendants and call queues?
They stay in your Microsoft tenant. Their phone numbers sit on resource accounts, and at cutover those numbers are unassigned from Telstra and reassigned on Summit. Your migration specialist handles the sequence with you so callers are not left hearing a dead line.
What does the free number porting offer include?
Free porting of the local numbers (geographic numbers such as 02, 03, 07 and 08 numbers) attached to your Telstra service when you move to a Summit voice plan. It is a one-time offer for Telstra customers and expires on 30 August 2027 unless extended. 1300, 1800 and 13 numbers are not included.
Are there exit fees for leaving TCO365?
Telstra's critical information summary for TCO365 describes it as month to month with no early termination charge. Businesses on a separate Telstra agreement may have different terms, so check yours with Telstra.
Is Summit part of Telstra or Microsoft?
No. Summit Internet is an independent Australian carrier (ACMA Carrier Licence #388) and is not affiliated with Telstra or Microsoft.
Get started

30 November is close. Lodge your port today.

Tell us about your Teams set-up and our dedicated migration team will start your port straight away, with your local numbers ported free.

Call 1300 049 749 · Mon-Fri 9AM-5PM AEST

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