Telstra and other RSP unexplained data usage increases

  1. MyTelstra internet usage has suddenly shot up for no apparent reason. Previously we would only use a fraction of our allowance but last month we suddenly ran out halfway through the month and are now again we are running out. Telstra are no help. A computer consultant I contacted said the number of people I’m seeing with this issue with Telstra is astounding. All with the same thing you’re seeing: going for years on very limited data, to suddenly having 10-20 times the regular usage. Seems like a Telstra scam to try to get us change to a higher cost plan. Has anyone else had this experience?

Do you hang smart devices off the NBN/wifi router? Many smart devices send data to and from the internet regularly and can chew up some data, especially if there are multiple devices running email, social media, messaging etc apps.

Have you changed your wifi password recently to ensure it is unique and not a default one?..someone within range of your wifi may be using it without your approval. I would be changing passwords for both the wifi and accessing the router.


Caveat - some RSPs give customers ‘locked down routers’ whereby they cannot see or change much. I do not know what Telstra provides or if you have your own. Presuming you have one from Telstra that is not ‘locked down’ or you have your own —

Most routers have a feature that shows the ‘traffic’ (data use). It is most often under ‘system tools’ or something similarly named, and often is turned off by default.

Your router will also show you a list of devices connected to your WiFi. It is sometimes only shown by the quizzical ‘MAC address’ rather than device name, but you should be able to count how many devices are reasonable to be connected. If you have ‘too many’ perhaps someone has gotten access and is using your network as @phb suggested?

If you post your make and model router we might be able to guide where to look.

The traffic display will show you if the router is sending/receiving that much data, or if there is something going on external to your premises.


Has some member of the family, a child or teenager perhaps, just got a new device? Have you just signed up for any streaming services?


Smartphones connected to the WiFi network will preference that over the phone Data allowance or even use both to speed up connections. Many people are then using their fixed service Data rather than phone data around their homes. Perhaps there has been a change in usage of such a device or one has recently been enabled on the network.

The Telstra Routers do show the connected devices in a ‘Network Map’ with all the attendant data eg MAC address. They, depending on the model of router, also show the data used by the device.

Another issue may be that updates are occurring and failing resulting in multiple retries, not knowing what data allowance is held this could also be a reason for finding the allowance quickly disappearing. If it is a Win 10 version update this could be around 3GB of data each try.

I’m happy to Teamviewer into the machine to check possibilities but @clubman may not wish this to happen.


A potential source of increased usage not covered by others is unmetered data in the past becoming metered now.
My ISP had a deal in the early days of streaming services like netflix and stan to not count those in my monthly data usage. Sort of a sweetener to get users to use their service.
Perhaps your provider Telstra is now metering data that in the past was not counted.
Just a thought.


Fing is worth a look. I use the app in its free state and thats enough for me.
[edit] And I now withdraw the recommendation. At the moment it seems incapable of identifying devices correctly. I’ll delete and reinstall and see how it goes. It was great… at frst. [edit#2] Dud. I’ve switched to something else on iOS.

A friend has the Fing hardware and swears by it. He loves his Fingbox.

I should say this isn’t going to deal with Telstra, but it will let you see if there are any strays on your network, eating your bandwidth.


A check of Telstra’s NBN offer has nothing but unlimited data plans.

Are you on a data capped older NBN plan (or saddled with NBN fixed wireless or sat service), or yet to meet with the NBN still on ADSL, or are you on a wireless dongle?


Reading the original post could even be a mobile, we may have assumed it was broadband.

If it is a mobile, more and more apps are data hungry and will chew into data allowances.


If you want to get an idea of at least who made the device with that weird MAC address, there’s a tool for that.

Note: do not enter the entire MAC address, and do not publish it online. Almost all network-connected devices have their own unique MAC address. (Almost all, because Apple has changed iDevices to broadcast fake addresses to avoid trackers. I am unsure of the details, but they probably still show themselves as being made by Apple.)

I agree that Fing can be handy. There are also free desktop programs available that will identify devices on your network. Note: while the linked website appears to provide links to the software publisher’s website, I strongly recommend that you type the publisher’s address yourself - or do a search and use the result from that. This applies to anything you download from the Internet - make sure you know and trust the source.


If the explanations for increased data usage still don’t explain it and Telstra are not giving you any more clarity on the increase, despite requests, you could refer your matter to the Telecommunications Industry Ombudsman (TIO) - I have done so with Telstra in the past and it was very effective, efficient and free, and I was very happy with the outcome. If it is a systemic problem as you say, reporting it will also assist the TIO in identifying any trends and help to protect all consumers.


Google “best free network analyser”, install one, and figure out which device and application are generating the traffic. If you can’t do that yourself, get some other IT-savvy person to do it for you.

It could even be malware installed by cybercriminals using a device for bitcoin mining, hosting a criminal website in a hidden virtual machine, using your device for DDOS attacks, or some such.

It is highly unlikely that it is a Telstra scam. The anecdotal report that lots of people have this problem is probably more a sign of pervasive malware activity.


Any amazon (ie ‘ring’) devices? or any networked cameras?

Amazon are are doing their whole public ‘mesh’ (on by default etc) and that whole suite of devices has had a consistent issue with security.


Not enabled in Australia yet if you are talking about the Wireless Network transmitter feature (Sidewalk) they will be enabling first in the US on the 8th of this Month. Though it will be progressively rolled out elsewhere. Mostly need to watch out for Ring & Echo devices. It won’t be using normal household data but a specially selected frequency (915 MHz) that in most of the World is free to use.


Me too

I have had the opposite problem. On ADSL I have not seen my data usage since March 2020. I’ve attempted to get it a number of times, including through the CEO’s team via (a handy email for service). The TIO has not been successful and I spoke to three technicians
in the last week who couldn’t give it to me. This has meant I’ve had no data usage to make an informed choice about which NBN plan to choose. My remaining option is to switch to NBN with Telstra and hope it will finally register data usage as promised.

Not the original topic exactly, but a very unusual situation. Unless your ADSL plan has unlimited data at full plan speed?

If you are still on ADSL it suggests you are in an NBN Fixed Wireless or Satellite area. The first option may be better, the second may not be so.

Is there any real need to stay with Telstra if you move to the NBN? I can think of only one assuming you wish to keep your fixed copper line for phone backup. It’s cheaper with Telstra than with other providers.


I’m on copper line ADSL - meant to change to NBN yesterday but they didn’t turn up. Many reasons to leave Telstra due to mostly appalling service which has high hours/stress costs. I’ve delayed so I could stay on ADSL due to inadequate mobile reception for power outages more frequent here on the bushfire prone edge of Melbourne. Telstra’s excuse for 0 data use recorded was they’d switched everyone to unlimited data due to the pandemic, but that stopped last year. I can’t risk switching to a low data plan until I know how much data I’m using. It could have skyrocketed like the initiator of this thread. Data use details should be a right.

Can you log into your modem?

I share that pain in Eltham, but Telstra is not going to provide you anything any other RSP could when you move onto the NBN. With NBN all your RSP delivers to you are its own servers and call centre. The infrastructure is all NBN between your router/modem and their server. With HFC and some other NBN technologies even the modem is NBN, not the RSP, and becomes part of your house in context - eg if you move the modem stays. Have a problem they cannot resolve on the phone? All any of them can do is, I repeat, report it to NBN and make a booking for an NBN technician to come have a look.

Depending on your budget, the differences from RSPs between capped and unlimited plans or speeds is most often about $10 pcm from tier to tier. There are usually no contracts and allow changing from plan to plan almost at will. Many no longer offer capped plans. If you sign up for a plan regardless of who with, confirm that and go for what you think you need, and watch it and change it as required. It is only a visit to your account management on their website, or a phone call and while many stress about doing it, it is more painless than changing electricity suppliers.


I had an identical problem 15 years ago with Telstra BigPond dial-up… regular monthly data use suddenly sky-rocketing thru the roof and Telstra blamed me, of course. There were only 2 people in the house, myself and a primary school child who didn’t use the computer.
My house was empty for a period of 3 months as we travelled overseas and guess what, we exceeded our data allowance, and still, Telstra blamed me.
The topic arose at a friends BBQ gathering and to our astonishment, five of the six couples were having the exact same problem with Telstra BigPond. The one other couple were with a different service provider.
That convinced me to change providers and I’ve never experienced any issues since at home or at place of employment.
Telstra were condescending and unhelpful.
I’ll never be a Telstra customer again for any product… oh, and I use to work for them for 25 years!