Telstra DOT and T-Biz Voice Switch Off on 30 August 2027. Keep Your Local Numbers, Free.
Telstra is retiring T-Biz Voice on the nbn and DOT (Digital Office Technology) and has not named a replacement. Summit's dedicated DOT migration team moves your phone numbers, handsets and internet onto a business nbn + 4G backup bundle with a cloud phone system, and ports the local numbers on your Telstra service free of charge.
One-time offer for Telstra customers
Free local number porting when you move your T-Biz Voice or DOT service
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.
Overview
If your business phones run on Telstra T-Biz Voice on the nbn or Telstra Business Internet (DOT), the clock is running. Telstra has published an exit notice for both products, citing "hardware limitations". Sales stopped on 30 September 2025, and since then you cannot add lines, move premises or recontract. On 30 August 2027 both services stop working altogether.
| Telstra product | No changes or recontracts from | Exit date (service stops) |
|---|---|---|
| T-Biz Voice on the nbn (also called Business Voice on nbn) | 30 September 2025 | 30 August 2027 |
| T-Biz Unified (nbn broadband + T-Biz Voice) | 30 September 2025 | 30 August 2027 |
| Telstra Business Internet (DOT, Digital Office Technology) | 30 September 2025 | 30 August 2027 |
Telstra's customer terms put it plainly: on and from 30 August 2027, DOT "will be withdrawn from the market and no longer be provided to all customers". T-Biz Voice, renamed Business Voice on nbn in 2019 but still known to most businesses as T-Biz, has the same withdrawal date.
Telstra's notice tells you the dates. It does not tell you what to move to, what happens to your phone numbers, or what to do about the EFTPOS terminal, back-to-base alarm or fax machine plugged into the same box. That is the part that goes wrong when a business leaves it to the last month, and it is exactly what our DOT migration team does every day.
Because DOT bundles your internet with your phones, replacing it is not just a phone decision. When the DOT gateway goes dark, your internet goes with it. Summit replaces both in one move: a business nbn service with automatic 4G backup, and a cloud phone system (hosted PBX, Microsoft Teams Calling or SIP trunks) running over it, with your existing numbers ported across at no charge.
Summit Internet is an independent Australian carrier (ACMA Carrier Licence #388) serving businesses since 2000. We are not affiliated with Telstra. For your own service details and dates, check your Telstra notice or call Telstra on 1800 926 478.
Key Benefits
-
A Dedicated DOT Migration Team
Your move is run by Summit's dedicated DOT migration team, not a general sales queue. They audit your Telstra service, list every number and every device on the line, plan the cutover and stay with you until the last number has moved. You are not passed between sales, provisioning and support.
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Free Local Number Porting
Move your T-Biz Voice or DOT service to a Summit voice plan and we port the local numbers attached to your Telstra service with no porting fee: your main line, extra lines and fax numbers (for example 02, 03, 07 and 08 numbers). Your customers keep dialling the numbers they already know. A one-time offer for Telstra customers, available until 30 August 2027 unless extended.
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nbn + 4G Backup + VoIP in One Bundle
DOT combined internet and phones in one box. So does our replacement, done properly. Business nbn with a static IP, automatic 4G failover when the nbn drops, and your cloud phone system on top, on one invoice with one support number. When the nbn has a bad day, your phones and EFTPOS keep working on 4G.
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Your Phones Get Voice Priority
When your phone system runs on a Summit connection, we prioritise voice traffic over everything else on the line. Calls stay clear while someone uploads files or streams a training video. That is something you cannot get when your phones and your internet come from two different companies.
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EFTPOS, Alarms and Fax Handled Before Cutover
Old Telstra business lines often carry more than calls. Our migration team checks for EFTPOS terminals, monitored alarms, fax machines and lift phones before anything moves, and plans a working path for each one. Nothing gets discovered the morning it stops working.
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Cutover on a Day You Choose
Move now and your cutover happens on a quiet day you pick, tested in advance. Leave it to winter 2027 and you will be in the same queue as every other T-Biz Voice and DOT business in Australia, racing a hard switch-off date.
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Features DOT Never Had
Auto attendant ("press 1 for sales"), ring groups, call queues, voicemail to email, time-of-day routing, call recording and mobile apps that make and take calls on your business number. Every feature is included in one per-user price, with no feature packs.
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A Phone System That Moves With You
Since 30 September 2025, you cannot move a T-Biz Voice or DOT service to new premises. A cloud phone system is not tied to a box or an address. Move office, add a second site or send someone home and the phones simply go with them.
Your DOT Features, and What Replaces Them
Most DOT and T-Biz Voice businesses rely on a handful of features they set up years ago and have not thought about since. Here is what each one becomes on Summit. On DOT, several of these were paid add-ons; on Summit hosted PBX they are included in the per-user price.
| What you use on Telstra DOT or T-Biz Voice | What it becomes on Summit |
|---|---|
| Hunt Group | Ring groups and call queues, included |
| Virtual Receptionist | Auto attendant (IVR) with your own greeting, included |
| MessageBank and Voice2Email | Voicemail to email, included |
| Call Conductor or CommPilot portal | Summit web management portal |
| DOT App or Telstra Business Connect softphone | Summit mobile and desktop apps on your business number |
| Ad On Hold | Custom hold music and on-hold messaging |
| Voice and Broadband Backup (4G) | Automatic 4G backup on your Summit nbn |
| Dedicated EFTPOS and Fax lines | EFTPOS over nbn with 4G backup, fax to email |
| Office Plan extra lines | Extra users and numbers, added in minutes |
DOT also tied you to a Telstra-supplied gateway, with two analogue phone ports before you needed extra hardware. A cloud phone system is not limited by the box on the wall: add users, numbers and sites whenever you need them.
How It Works
- 1 Submit your enquiry
Submit your enquiry
Fill in the form above or call 1300 049 749. Tell us whether you are on T-Biz Voice or DOT and which numbers you want to keep. A recent Telstra bill speeds everything up.
- 2 Our dedicated DOT team calls you
Our dedicated DOT team calls you
A specialist from our DOT migration team calls to discuss your requirements: how your business answers calls today, the local numbers on your Telstra account, and every device that depends on the line, such as EFTPOS, alarms, fax and lift phones.
- 3 Choose physical handsets or go softphone only
Choose physical handsets or go softphone only
Select how many desk or cordless handsets you need, or go softphone only and take calls on the Summit app on your mobile and computer. Mix the two if that suits your team.
- 4 We preconfigure and ship your new hardware
We preconfigure and ship your new hardware
Your handsets and your nbn and 4G backup hardware arrive preconfigured, with your extensions, auto attendant and ring groups already set up. Plug them in; there is nothing to program.
- 5 Migration support from our DOT team, start to finish
Migration support from our DOT team, start to finish
Your DOT team ports your local numbers on the day you choose, tests inbound and outbound calls with you, and checks EFTPOS and alarms on the new connection. Only then do they tell you what to cancel with Telstra. Porting may not automatically cancel the rest of your Telstra service, such as the DOT or T-Biz nbn broadband, and cancelling first is worse: a disconnected number can no longer be ported.
Features
What Is in the Migration Bundle
- Business nbn
- : Business-grade nbn with a static IP included, sold by a business-only provider.
- Automatic 4G backup
- : A 4G failover router alongside your nbn that switches over automatically when the nbn drops and back again when it returns.
- Cloud phone system
- : Hosted PBX, Microsoft Teams Calling or SIP trunks, chosen to suit how your business takes calls.
- Free local number porting
- : The local numbers attached to your T-Biz Voice or DOT service ported to Summit with no porting fee. 1300 and 1800 numbers can be ported too, outside this offer.
- Handsets
- : Desk phones, cordless DECT handsets, reception consoles and softphone apps, configured before cutover.
- One bill, one support number
- : Internet, phones and backup on a single Summit invoice.
What Your DOT Migration Team Handles
- Telstra service audit
- : Every number, line and device on your current service, listed before anything changes.
- Porting paperwork
- : We prepare the porting authority and check it against your Telstra account details so it is not rejected.
- Call flow design
- : Your current call handling recreated, then improved: who answers first, where calls overflow, what happens after hours.
- EFTPOS and alarm planning
- : A working path for every device that used the old line, agreed before cutover.
- Cutover testing
- : Inbound, outbound, transfers, voicemail and attached devices tested on the day.
- Telstra exit guidance
- : What to cancel, when, and how to avoid paying for both services longer than necessary.
Phone System Features Included
- Auto attendant (IVR)
- : A professional greeting that routes callers to the right person or team.
- Ring groups and call queues
- : Ring several phones at once or in turn, and hold callers in a queue during busy periods.
- Voicemail to email
- : Messages delivered to your inbox as audio files.
- Time-based routing
- : Different call handling for business hours, after hours and public holidays.
- Mobile and desktop apps
- : Make and take calls on your business number from a mobile or laptop.
- Call recording and reporting
- : Record calls for training or compliance and see call volumes and missed calls.
Hosted PBX or Microsoft Teams Calling?
Most T-Biz Voice and DOT businesses land on one of two replacements. Our migration team will recommend one based on how your business actually works, and we are happy to say if the simpler option suits you.
Summit Hosted PBX
- Best for
- Shops, clinics, trades and offices that answer calls on desk or cordless phones.
- How it works
- A complete cloud phone system with handsets, auto attendant, ring groups and queues, managed from a web portal.
- Pricing
- From $15 per user per month, every feature included.
- Good to know
- Pairs naturally with our nbn + 4G backup bundle, with voice priority across our network.
Microsoft Teams Calling
- Best for
- Office teams that already live in Microsoft 365 and Teams.
- How it works
- Summit connects your Teams to the phone network, so staff call from the Teams app they already use.
- Pricing
- Requires Microsoft Teams Phone licences in addition to Summit calling.
- Good to know
- Desk phones are optional; most staff use a headset and the Teams app.
Moved to Telstra Calling for Office 365 at some point? Telstra's terms show that product is being withdrawn too, on 30 November 2026. Summit Teams Calling connects to the same Microsoft Teams you already use: see our Telstra Calling for Office 365 replacement page. Already have a phone system you like? We can also connect it with Summit SIP trunks and port your numbers to those instead.
Use Cases
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The Café on DOT With EFTPOS on the Line
Hospitality & TourismA café runs its phone and internet through a Telstra DOT gateway, with EFTPOS depending on that connection. Summit ships preconfigured nbn and 4G backup hardware, moves the café number to a cordless handset on our hosted PBX, and confirms EFTPOS is processing on the new connection before the Telstra service is closed.
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The Medical Practice With Four T-Biz Voice Lines
Dentists & GPsA suburban clinic has four Telstra numbers, a fax line for referrals and a reception that cannot afford a missed call. Our migration team ports all five local numbers free, sets up a queue for reception with overflow to the practice manager, and turns the fax line into fax to email so referrals arrive in the inbox.
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The Trades Business That Lives on Mobiles
TradiesA plumbing business still has a Telstra landline number on its van signage, but the office phone rarely gets answered. We port the number to hosted PBX and ring the office and the owner's mobile app at the same time, so the number on the van never goes to a dead line again.
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The Accounting Firm Moving Office
Lawyers & AccountantsA firm on T-Biz Voice wants to move premises next year and discovers it cannot move the Telstra service. Summit sets up nbn, 4G backup and Teams Calling at the new office, ports the numbers on moving day and the phones work on the first morning.
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.
Lock in free local number porting before the 2027 rush
Every T-Biz Voice and DOT business in Australia has the same deadline. Port early and your cutover happens on a day you choose, tested in advance, instead of in a queue in August 2027.
Why Choose Summit
- 01
We Have Done This Before
Summit has been moving businesses off closing and legacy phone services since 2000: ISDN and PSTN shutdowns, the nbn rollout and providers leaving the market. A retirement date is a project with a deadline, and we treat it like one.
- 02
A Licensed Carrier With Its Own Network
Summit is an ACMA licensed carrier (Licence #388) that builds and runs its own voice and data network. When your phones and internet are both on Summit, one company can see the whole path, and fix it.
- 03
Business Only
We do not sell residential services. Our processes, support and priorities are built around businesses whose phones are their front door.
- 04
One Team From Quote to Cutover
The same migration specialist who audits your Telstra service is the one who runs your cutover day. Nothing gets lost in a handover.
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Bundle them on one bill →Why Australian Businesses Choose Summit Internet
Great business and service provider. Highly recommended.
Nabil Salameh
last month
The Summit Team have always been a pleasure to work with; we highly recommend their services. Thank you for the continued support.
Paul Braithwaite
5 months ago
We recently moved our dental practice over to Summit for phone services, and the experience has been excellent from start to finish. The team has been responsive, professional, and incredibly helpful throughout the entire setup process. The transition was smooth, any issues were addressed promptly, and communication was always clear and efficient. Reliable phones and internet are essential for a busy practice like ours, and Summit has delivered exactly that. A special thank you to Michael for his patience and ongoing assistance during the transition. Highly recommend Summit to any business looking for reliable service and great customer support.Read more
Elli Darabi
5 months ago
The best service !!! Got issue fixed out by Greg ^^
白大倫
5 months ago
The whole team at Summit have been great from the initial onboarding to the rapid responses from Max when we need to make changes or additions to our services. Can't recommend them enough!
Aaron Klaver
5 months ago
As the I.T. Manager for Hydronic Systems Australia, Summit helps provide me and our companies with consistently stable Business Grade Internet, backed up by a dedicated Fixed Wireless Broadband connection. They also saved us a serious amount of money on our mobile phone bills. We have had no serious issues, and our business has been rock-solid under there great service. Highly Recommended.Read more
James Paterson
6 months ago
Prompt and efficient service. Highly recommend
Elliot Bell
6 months ago
We now use Summit across our real estate network. Great family business, reliable and their attention to detail is outstanding. Highly recommend.
Ryan Bell
6 months ago
As a reseller, we primarily work with Summit’s 4G services and have been very impressed. The plans are affordable, flexible, and well suited to our customers—especially for internet failover solutions. The sales and support teams are responsive and genuinely helpful, which is why we’re proud to partner with Summit Internet. We happily recommend them.Read more
Mal Skinner
6 months ago
After working with another ISP for several months to deliver a critical internet service for a major international sporting event, we were ultimately advised that the required upgrade was unlikely to be completed prior to event week. This left us facing a significant risk to service delivery. After exhausting all other options (and a few sleepless nights) we came across Summit Internet. From the initial conversation, Allan immediately understood the severity of the situation and quickly engaged his technical delivery team. Michael “Radar” was on site within days to assess and finalise a solution. Despite challenging conditions, including large trees and other obstructions, he worked tirelessly to design and implement an alternative approach. Leveraging an adjacent building, a temporary NBN connection, and a wireless link into the comms room, the solution was delivered within 24 hours of the initial site visit. Not only was the outcome faster than expected, but it was also more cost effective and delivered higher speeds than originally promised by the previous ISP. Over the course of the event, the service handled terabytes of data and supported hundreds of concurrent users without a single speed or performance issue. I cannot thank Summit Internet, particularly Allan and Radar enough for their exceptional service, technical expertise, and commitment to delivering under pressure. Highly recommended.Read more
Adam Hastie
6 months ago
Fausto and the staff at Summit are amazing. We have had nothing but fantastic service from start up to problem solving issues. The system is easy to use. Would highly recommend this service provider.
Jo Bodhankar
6 months ago
Summit internet recently set my small business up with a local land line number and a soft phone that runs off an app on my mobile - getting my personal phone number off the internet and being able to distinguish between business and personal calls is a game changer. Whole process took less than a week, and is super cost effective. Highly recommend.Read more
Alex Holly
8 months ago
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Frequently asked questions
When do Telstra T-Biz Voice and DOT stop working?
What is Telstra DOT (Digital Office Technology)?
What is T-Biz Voice, and is it the same as Business Voice on nbn?
What is the replacement for Telstra DOT and T-Biz Voice?
Can I keep my existing phone numbers when I leave Telstra?
Should I cancel my Telstra service before I switch?
What happens to my numbers if I do nothing before 30 August 2027?
What does the free number porting offer include?
What happens to my EFTPOS, alarm and fax machine?
Will my internet stop when DOT is switched off?
How long does porting from Telstra take?
Do I have to pay Telstra to leave before August 2027?
Can't I just move to another Telstra product?
Is Summit part of Telstra?
Keep your local numbers. Beat the 2027 switch-off. Port free.
Tell us what is on your Telstra service and our DOT migration team will plan a cutover on a day that suits you, with your local numbers ported free.
Call 1300 049 749 · Mon-Fri 9AM-5PM AEST