Telstra Business Phone System Changes: What Do They Mean for Your Business?

Telstra is making significant changes to several of its legacy business phone and voice services, and Australian businesses using these products need to understand what is changing and when. The changes affect services including Telstra Calling for Office 365 (TCO365), T-Biz Voice on the nbn and Telstra Business Internet (DOT), while Telstra Business SIP is no longer available to new customers. The announced retirement dates vary by product, with some services already closed to new sales or changes and others scheduled to end in 2026 or 2027. For businesses with existing Telstra phone systems, this does not mean that Microsoft Teams, VoIP or business phone systems are disappearing. Instead, affected businesses may need to review their current service and consider a replacement or migration before their existing Telstra service reaches its withdrawal date.

This is particularly relevant for businesses using Microsoft Teams for calling, including organisations affected by the withdrawal of Telstra Calling for Office 365 on 30 November 2026. In this guide, we explain which Telstra business phone services are affected, the important dates businesses should know, what the changes mean for Microsoft Teams users and the options available when replacing an existing Telstra business phone system. Pasted markdown

Is Telstra Withdrawing From the Business Phone System Market?

Telstra is not withdrawing from the entire business phone system market. The current changes are focused on retiring several legacy business phone and voice services. Telstra continues to offer newer cloud-based communication options, including solutions that integrate business calling with Microsoft Teams. One example is Operator Connect for Microsoft Teams, which allows businesses to connect their Teams environment to the public telephone network through participating operators. For businesses using an affected legacy Telstra service, the key issue is therefore not whether business phone systems are disappearing, but which service they currently use and what replacement or migration option is suitable.

Telstra’s business service changes provides further information about the affected services and announced changes. If your business uses Microsoft Teams for calling, you may also need to review your Microsoft Teams calling options before your current Telstra service reaches its withdrawal date.

Which Telstra Business Phone Services Are Being Retired?

Telstra has announced changes to several legacy business phone and voice services. The retirement dates differ depending on the service:

Telstra service	Current status	Withdrawal/exit date
Telstra Calling for Office 365 (TCO365)	No longer available to new customers; existing customers can no longer make changes or recontract	30 November 2026
T-Biz Voice on nbn	Retired from new sales and changes	30 August 2027
Telstra Business Internet (DOT)	Retired from new sales and changes	30 August 2027
Telstra Business SIP	No longer available to new customers	Existing customers can continue until further notice

The exact impact depends on the Telstra service your business currently uses. Businesses should check their service name, current contract and any communications received from Telstra before making changes. For more information about TCO365, see Telstra’s official information page.

Telstra Calling for Office 365 Is Ending

Telstra Calling for Office 365 (TCO365) is one of the key services affected by Telstra’s announced changes. Existing customers need to plan ahead as the service approaches its withdrawal date.

• TCO365 stopped accepting new customers in November 2024.
• From 30 August 2026, existing customers can no longer add services, make changes or recontract.
• TCO365 will be withdrawn on 30 November 2026.

Importantly, Microsoft Teams itself is not being discontinued. TCO365 provides the PSTN connectivity that allows businesses to make and receive external telephone calls through Microsoft Teams. Businesses using TCO365 will therefore need to consider another calling and PSTN connectivity solution. For businesses affected by the change, see Telstra Calling for Office 365 Is Ending: What Australian Businesses Should Do Next for more information about the transition and available options.

What Does This Mean for Businesses Using Microsoft Teams?

Businesses using Microsoft Teams for calling can continue to use Teams after TCO365 is withdrawn. However, they will need another way to connect Teams to the public telephone network.

The basic setup is:

Microsoft Teams → PSTN connectivity → Telephone network

TCO365 provided this PSTN connectivity for businesses using Teams. After its withdrawal, businesses may need to review:

• Microsoft Teams Phone licensing
• Existing business phone numbers
• Main and direct numbers
• Auto attendants
• Call queues and hunt groups
• Call routing
• Voicemail
• Existing handsets and devices
• Microsoft 365 licences
• Number portability

Businesses should review these requirements before choosing a replacement, as the right setup will depend on how their current Teams calling environment is configured. You can also learn more about Microsoft Teams Calling Costs Australia when reviewing the potential costs of moving to a new Teams-based calling solution.

What Can Replace a Telstra Business Phone System?

Businesses affected by Telstra’s service retirements may have several replacement options. The right choice depends on the business’s existing phone setup, Microsoft environment, numbers, calling requirements and desired features.

1) Hosted Business Phone System

A hosted business phone system provides a cloud-based alternative to traditional phone systems. It can support features such as call queues, IVR, voicemail, desktop and mobile calling, and remote work. Businesses can explore. Business Phone Systems to see how a hosted solution could fit their communication needs.

2) Microsoft Teams Phone

Microsoft Teams Phone allows businesses to use Teams as the interface for business calling when it is combined with the appropriate PSTN connectivity. Teams itself does not automatically replace a complete business phone system. Businesses still need to consider their phone numbers, calling features, licensing and PSTN connection.

3) Direct Routing

Direct Routing connects Microsoft Teams Phone to a telecommunications provider through a certified Session Border Controller (SBC). This can provide businesses with greater flexibility over their existing telephony setup and connectivity. For technical details, see Microsoft’s Direct Routing documentation

4) Operator Connect

Operator Connect allows businesses to connect Teams Phone to the public telephone network through participating telecommunications operators. It is integrated directly with Microsoft Teams and can simplify the process of managing business calling. The most suitable option will depend on your Microsoft environment, existing numbers, call flows, licensing and overall business requirements.

What Should Businesses Check Before Replacing Their Telstra Phone System?

Before choosing a replacement, businesses should review how their current phone system works and what needs to be carried across to the new solution.

1. Existing Phone Numbers

Check all numbers currently connected to the Telstra service, including:

• Main business number
• Direct numbers
• 13 and 1300 numbers
• Other numbers used by teams or departments

2. Current Call Flows

Document how calls are currently handled, including:

• Auto attendants and IVR
• Call queues
• Hunt groups
• Business-hours and after-hours routing
• Voicemail
• Call forwarding

3. Microsoft Environment

Review your existing Microsoft setup, including:

• Microsoft 365 licences
• Teams Phone licensing
• Teams users
• Existing Teams calling configuration

4. Handsets and Devices

Check which devices your staff currently use, such as:

• Desktop handsets
• Headsets
• Computers
• Mobile devices
• Teams-compatible equipment

5. Internet Connection

Cloud-based calling relies on a reliable internet connection, so businesses should also review their current connectivity before migrating. For businesses reviewing their connectivity options, Business Internet can be considered as part of the wider phone system migration.

Can You Keep Your Existing Business Phone Numbers?

In many cases, businesses may be able to keep their existing phone numbers when moving away from a Telstra business phone system. However, number portability depends on the specific number, service and replacement solution.

Before starting a migration, businesses should identify every number currently in use and confirm:

• Whether each number can be ported
• Who owns the numbers
• What documentation is required
• How long the porting process may take
• When the numbers should be migrated

Businesses should confirm portability with their new provider before making changes to their existing Telstra service.

When Should You Start Planning Your Telstra Phone System Migration?

Businesses should start planning before their current Telstra service reaches its withdrawal date. Starting early gives you time to review your setup, choose a replacement and test the new system.

A simple timeline is:

• Now: Identify your Telstra service and its withdrawal date.
• Before withdrawal: Choose a replacement, review numbers, licensing and call flows.
• Before migration: Test the new configuration and plan number porting.
• During migration: Move the service and verify numbers, inbound and outbound calls, and call routing.

For businesses using TCO365, the withdrawal date is 30 November 2026, so planning ahead is important.

Telstra Business Phone System Alternatives for Small and Medium Businesses

Businesses using affected Telstra services may need to review their current phone setup and consider alternative communication solutions. The most suitable option will depend on the number of users, phone numbers, licensing, calling features, hardware and how the business handles inbound and outbound calls.

Common options include:

• Hosted business phone system
• Microsoft Teams Phone
• Direct Routing
• Operator Connect
• Other cloud-based communication solutions

Businesses with smaller teams should not assume that the same replacement will suit every organisation. Reviewing the existing phone environment first can help identify which features and services need to be carried across.

Why Businesses Should Not Wait Until the Withdrawal Date

Starting the migration process early gives businesses more time to prepare their phone system and avoid last-minute disruptions.

• Plan for phone number porting
• Configure users and calling services
• Rebuild existing call flows
• Review Microsoft 365 and Teams licences
• Replace or configure handsets
• Familiarise staff with the new system
• Test inbound and outbound calling before the existing service is disconnected

How Broadconnect Can Help?

If your business currently relies on a Telstra business phone service that is being retired, Broadconnect can help you review your existing phone environment and plan the transition to a modern business communications solution. We can help businesses assess their current phone numbers, users, calling requirements, Microsoft Teams environment and connectivity requirements before recommending an appropriate solution. Whether you need a hosted business phone system or want to integrate business calling with Microsoft Teams, our team can help you understand the available options and plan your migration.

FAQs About Telstra Business Phone System Changes

Here are answers to some common questions businesses may have about Telstra’s business phone service changes.

Moving Forward With Your Business Phone System

Telstra’s changes mean affected businesses should review their current phone service and understand the relevant withdrawal date. Planning early can make it easier to manage phone numbers, calling features, Microsoft Teams requirements and the migration process.

If your business is affected by a Telstra service retirement, reviewing your options early can help you prepare for the transition without waiting until the existing service is due to end.

Call: 1300 880 330
Email: hello@broadconnect.com.au
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