Bad mobile reception at home? WiFi calling, and the boosters that are legal

Outside on the footpath the phone has full bars. Inside the house it has one, calls drop halfway through a sentence, and the only place it rings properly is the back step. For most homes the fix costs nothing: WiFi calling, which is probably already built into the phone. Here is how it works, the one catch that matters, which boosters are against the law, and when it is worth booking home tech support to set WiFi calling up on every phone in the house.

Why is mobile reception so bad inside my house?

Mobile reception is bad inside because the signal from the tower has to get through the walls and the roof, and brick, concrete and metal stop a lot of it. The same phone that shows full bars in the street can show one bar in the lounge room.

The usual culprits on our calls are the same few:

• Brick and concrete. Double brick houses, concrete floors between levels, and apartments, where the building and the ones beside it shield each other.
• Apartment blocks close together. One caller described a street of units as “known as the dead zone”: one bar indoors, and the carrier had said changing provider would not make much difference.
• Low ground. A house in a valley or below a ridge can sit in a shadow the tower does not reach well, even when the next street is fine.
• Basements and garages. We have dealt with a building whose basement had no usable signal at all, where the roof was the place to pick one up.

Poor reception matters for more than calls: a 4G personal alarm needs the same signal to call for help.

None of this is your NBN. The mobile network and your home internet are two separate networks, and a slow or dropping NBN connection is a different problem with its own fixes.

What is WiFi calling?

WiFi calling lets your mobile make and receive normal calls over your home internet instead of the mobile network. You keep your own number, the person you ring sees your number as usual, and there is no app to install. When the phone has a good WiFi connection and a poor mobile signal, the call goes over the WiFi.

It uses very little of your connection. Telstra puts it at about 100 to 120 kilobits a second, a sliver of even the slowest NBN plan. On a compatible phone Telstra says it is turned on by default, which is why some people have been using it for years without knowing. Some of our callers with one bar indoors already make their calls this way, one of them over a mobile broadband dongle while the house waited for its NBN connection.

Pick a situation

WiFi calling off WiFi calling on Power cut

Mobile tower Brick wall Your phone Modem (WiFi) NBN box To your carrier No power

WiFi calling off

With WiFi calling off, the call has to reach the tower through the walls. Inside a brick house that can be one bar, and the call drops.

WiFi calling on

With WiFi calling on, the call goes over your WiFi to the modem, out through the NBN box and joins your carrier's network from the street. The walls stop mattering.

Power cut

In a blackout the modem and the NBN box go off, so WiFi calling stops and the phone goes back to the mobile network. Keep the mobile charged and know where the signal is best.

The picture to keep in mind is the route the call takes. With WiFi calling off, the call has to reach the tower through the walls. With it on, the call goes from the phone to the modem over the WiFi, out through the NBN box and the street, and joins your carrier’s network from there. The walls stop mattering, but the modem, the NBN box and the power to both of them start to.

Is WiFi calling free?

Yes, on Telstra and Vodafone, which both say there is no extra charge for WiFi calling on their mobiles; calls are charged at your plan’s normal rates. Optus supports WiFi calling too, but the only Optus page we could check was written for its business customers, so ask Optus about your own plan. The data the call uses comes off your home internet plan, which on an unlimited NBN plan makes no difference.

WiFi calling on the three Australian networks, from each carrier's own support pages, checked 18 October 2026

Carrier	Extra charge	What you need	Calling 000
Telstra	None	A compatible phone; on by default; works on pre-paid too	Emergency calls in Australia still work
Optus	None, says its business FAQ; ask Optus about your plan	A compatible phone on the latest software	Mobile networks first, then WiFi calling; location may not be sent
Vodafone	None	A compatible phone on the latest software, with 4G calling (VoLTE) on	Only with no mobile coverage; location may not be sent

The phone matters as much as the plan. Each carrier keeps a list of compatible phones, and an older handset that is not on it may never offer the setting. If your mobile comes from a smaller provider, check its own list with whoever sends your mobile bill.

Buying a new phone for a parent? Check it supports voice over 4G, and the settings worth turning on.

How do I turn on WiFi calling?

On an iPhone it is in Settings, under Mobile, then Wi-Fi Calling. On a Samsung or other Android phone it is in the Phone app’s settings. Update the phone’s software first, because the setting can be missing on an old version.

1. 1

   Update the phone

   Install the latest software update. Vodafone also asks for 4G calling, called VoLTE, to be turned on in the phone's settings first.

2. 2

   iPhone: Settings, Mobile, Wi-Fi Calling

   Turn on Wi-Fi Calling on This iPhone and tap Enable. It may ask you to enter or confirm an address for emergency services. If you have two SIMs, pick the line first.

3. 3

   Samsung: Phone app, Settings

   Open the Phone app, tap the three dots, tap Settings and turn on Wi-Fi Calling. Some models also have a Wi-Fi Calling button in the quick settings panel when you swipe down from the top.

4. 4

   Check it is working

   On an iPhone, Wi-Fi appears in the status bar when you open Control Centre, and calls then use WiFi calling. Make a test call from the room with the worst signal.

If the switch is not there at all, the phone or the plan may not support it. Your carrier can tell you which, and Apple’s own guide to Wi-Fi Calling (opens in a new tab) has the iPhone steps with pictures.

What is the catch with WiFi calling?

The catch is that WiFi calling only works while your home internet works. If the power goes off, the modem goes off, and your calls go back to the mobile network, which is the one bar you were trying to get away from.

That is not a small point in a house with no reception. When the old copper phone lines were in, a phone plugged straight into the wall kept working in a blackout. On the NBN the home phone and the WiFi both run through equipment that needs mains power, and the ACMA says most NBN services will not work in a power outage. Our technician puts it simply to anyone relying on WiFi calling for something that matters: once the power goes, the router goes, and everything on it goes with it. Our post on NBN battery backup in a blackout covers what can be kept running.

The other ways it stops are the ordinary ones:

• The NBN is down. An outage, a fault or a modem that has dropped out takes WiFi calling with it. If that is happening now, start with how to check for an NBN outage.
• The upload is poor. Telstra and Vodafone both say a weak upload speed can disconnect a WiFi call, and a big download in the house can make the voice choppy.
• The connection has a long delay. Vodafone warns that satellite connections can reduce call quality, and one of our callers on an older satellite service found the delay made WiFi calling unusable.

Calling 000 on WiFi calling

You can call 000 with WiFi calling on, and the phone will still try the mobile network first. The ACMA says a 000 call from a mobile is carried on any available mobile network, not only your own carrier’s, and Apple, Optus and Vodafone all say the phone uses WiFi calling for an emergency call only when no mobile network can carry it. The ACMA also says you must be in the coverage of one of the mobile networks to call 000 from a mobile, so in a blackout, with the WiFi gone, know the spot in or outside the house where the phone picks up a signal.

Why does WiFi calling drop out in some rooms?

WiFi calling drops out in some rooms because the WiFi does not reach them. A call over WiFi is only as good as the WiFi where you are standing, so the back bedroom with no mobile signal often has weak WiFi too, and the call falls apart there instead.

People call two different things a “booster”, and it is worth keeping them apart. A WiFi booster is an extender or a mesh unit that spreads your home WiFi; a mobile booster claims to strengthen the mobile signal. For WiFi calling it is the WiFi one that matters. Our technician’s view of the plug-in WiFi boosters is blunt: they mostly repeat a WiFi signal that was already weak, which is why the one in the back window rarely fixes the room behind it. Whether WiFi range extenders really work has the long answer, and the best mesh WiFi for Australian homes covers what does reach.

Where there is a garage, a studio or a granny flat with no signal at all, a cable to that room and a WiFi access point there puts the WiFi where the calls are taken. That is a WiFi technician’s job, and it often starts with a cable run from the modem to a switch and an access point in that room.

If the WiFi is the weak link, a mesh system puts a unit near the room you call from.

We earn a small commission if you buy through our Amazon links, at no extra cost to you. As an Amazon Associate we earn from qualifying purchases.

Gear mentioned here, on Amazon Australia

Product	What it is for	Link
TP-Link Deco X55, 3-pack	WiFi 6 mesh for most homes	View on Amazon for the TP-Link Deco X55, 3-pack (opens in a new tab)
Mercusys Halo H60X, 3-pack	WiFi 6 mesh for a smaller home	View on Amazon for the Mercusys Halo H60X, 3-pack (opens in a new tab)

Are mobile phone boosters legal in Australia?

No. The ACMA says mobile phone boosters are illegal in Australia: you are not allowed to operate, supply or have one. Only a repeater that a mobile carrier has authorised is legal, and that authorisation comes from the carrier, not from the shop that sold it.

The reason is interference. The ACMA says a booster can disturb the mobile network badly enough that someone calling 000 may not get through, and can weaken the network for other users. The penalties include heavy fines and prison. The ACMA also warns to be wary of online sellers, whose products may not be legitimate, and to check with your carrier before buying.

What about a carrier-approved repeater?

A carrier-approved repeater is legal, but it is a bigger and more expensive fix than WiFi calling. It picks up the weak signal outside with an antenna and re-sends it inside the house, on that one carrier’s network.

Telstra’s range is the Telstra GO Repeater. Telstra’s own page says the repeaters receive a signal from a nearby Telstra mobile base station before amplifying it, so there has to be some signal to work with, and it recommends professional installation, especially for the stationary units. For Optus or Vodafone, ask the carrier which repeaters it authorises for your address.

Our technician’s advice on the calls about these is the same each time:

• There is an antenna on the roof and a cable down into the house. It is an installation, not a plug-in box.
• It is locked to one carrier. If you are on one network and your partner is on another, one repeater helps only one of you, and you would need two.
• It may not do the job. In a really bad spot it can be worth trying, but nobody can promise it will work before it is in. Some of the cheaper home units are hit and miss.
• Check the signal where it will go first. Go up on the roof, or as high and as far out as you safely can, and see how many bars the phone gets there. If it is close to nothing up there too, a repeater has little to work with.

In an apartment, ask the neighbours what they have done: same building, same problem.

How many bars do I need?

Two to three bars on your phone is generally workable, and three is good. That is the rule of thumb our technician gives for equipment that has to rely on the mobile signal, such as an emergency lift phone, and it is a fair test for a phone call too. Walk to the exact spot with the phone and look, because one corner of a house can be very different from the room next to it.

If the spot that matters has one bar or none, WiFi calling is the answer for phones, and for equipment that cannot use WiFi calling the antenna has to go where the signal is. That is why an emergency lift phone on 4G in a basement often needs an outside aerial run in before it will dial out reliably.

Setting up WiFi calling for a parent

Setting up WiFi calling for a parent takes ten minutes if the phone supports it. Do it in their home, on their WiFi, and test a call from the chair they actually sit in.

While you are there:

• Update the phone and check WiFi calling is on.
• Make sure the WiFi reaches the rooms they use, the bedroom included.
• Explain the blackout rule. If the power goes off, so do WiFi calls; a charged mobile and knowing where the best signal is in the house is the plan for that.
• Show them how to give their address if they ever ring 000, and put Emergency+ on the phone.

If you cannot get there, or the phone, the WiFi and the passwords are all a tangle, that is exactly what a home tech support visit sorts out, with someone in the family on the phone for the account passwords at the start.

When to call a technician, and when you don’t need one

You do not need anyone to turn on WiFi calling. It is in the phone’s settings, it costs nothing extra on Telstra or Vodafone, and your carrier will help if the switch is missing. Poor reception itself is your carrier’s to look at: the ACMA’s advice is to talk to your telco, which can check for network problems at your address and tell you what it approves. If your carrier recommends a repeater, ask who installs it; Telstra recommends professional installation for its GO Repeater.

Call us when the problem is on the home side:

• The WiFi does not reach the rooms where calls are taken. A WiFi technician finds why and puts the signal there.
• A garage, studio or back room needs its own WiFi for calls, and that means a cable and an access point. That starts as data cabling.
• Phones, tablets and the WiFi all need setting up, for you or for a parent. That is a home tech support visit.

Not sure which it is? Send us a message saying where in the house the calls drop, and we’ll tell you whether it sounds like the mobile signal, the WiFi or both.