The signal bars are not the problem
The complaint is always the same: full bars, and the call drops in the kitchen. The reason is that the bars describe a data connection and the call may be travelling a different way entirely. As older networks have been switched off across much of the world, voice has moved onto the modern data network, and whether your phone can use it depends on a setting, your carrier, and sometimes the exact variant of the handset you bought. Getting the two relevant switches on solves an enormous proportion of indoor call problems.
What is actually happening
Two features matter. Voice over LTE carries the call over the modern data network instead of falling back to an older one, which means better sound and no dropping off data mid-call. Wi-Fi calling carries the call over your home or office wireless network and out through the internet, so it works where there is effectively no mobile signal at all. Both are carrier features, not phone features: the handset supports them, the carrier has to enable them for your account, and the phone has to be a variant the carrier recognises.
That last point catches people out constantly. A phone bought in a different country, or an unlocked model bought directly from the manufacturer, may not show a Wi-Fi calling option at all on a given network, because carrier support is maintained per model. It is not a fault, and it is not usually fixable from the settings.
Buildings are the other half. Modern insulation, metallised window coatings, concrete and basements all attenuate the signal heavily, and the higher-frequency bands that carry the most data are the ones that penetrate walls worst. This is why a phone can show a good connection standing at a window and nothing three metres inside the same room.
Advertisement
Turning them on
- Check the carrier supports it on your plan Both features are commonly included, but some carriers restrict them by plan or exclude certain handset variants. Their support pages usually list which phones are approved.
- Update the carrier services and the system Carrier settings arrive through system and carrier services updates. A phone several updates behind frequently lacks the option entirely.
- Find the switches under the SIM Typically Network and internet, then SIMs, then the specific line. The names vary: VoLTE may appear as HD Voice, 4G Calling, Advanced Calling or similar.
- Turn Wi-Fi calling on and set its preference There is usually a choice of preferring wireless or preferring the mobile network. Prefer wireless if the building is the problem, which is the whole reason you are here.
- Register an emergency address if asked This is not optional bureaucracy. A call to emergency services over a wireless network cannot be located the way a mobile call can, so the address you enter is what gets passed on.
- Restart the phone and test both Call somebody from the room where calls fail. The status bar should indicate a wireless call. Then turn the wireless network off and confirm the call survives the handover, or at least does not drop instantly.
- If there is no option at all, ask the carrier Before concluding the phone is at fault. Provisioning on the account is the usual explanation, and it is something they can change at their end.
Matching the symptom to the cause
| What happens | Likely cause | What to try |
|---|---|---|
| Full bars, call drops indoors | Voice falling back to a weak legacy network | Enable VoLTE, then Wi-Fi calling |
| Data fine, calls impossible | Voice and data on different paths | Enable VoLTE; check the carrier provisioned it |
| Calls fine, no data during a call | No VoLTE, so voice pre-empts data | Enable VoLTE |
| Wi-Fi calling drops after a minute | Poor or congested wireless network | Test latency and loss; try the 5 GHz band |
| Call drops when leaving the house | Handover from wireless to mobile | Set the preference to mobile when out |
| No Wi-Fi calling option exists | Carrier, plan or handset variant | Ask the carrier; it is rarely fixable locally |
| Everything worse since a recent change | Legacy network shut down in your area | VoLTE is now mandatory, not optional |
Tools for working out where the problem is
Shows actual signal strength in dBm, which band you are on and which technology is carrying the connection. The bars are a rounded summary; this is the number that tells you something.
Which mast you are connected to and where the others are, which explains a great deal about why one room in a house is worse than another.
Coverage maps by carrier plus a straightforward speed test. Useful for the question of whether a different carrier would actually be better at your address.
Tests the broadband behind the wireless network. If Wi-Fi calling is unreliable, the line it runs over is the first thing to rule out.
Latency, jitter and packet loss. These are what break a wireless call, and a connection can look fast on a speed test while failing badly on all three.
Channel congestion at home, for the common case of every neighbour on the same channel. Recent Android versions limit how often apps may scan, so readings update slowly.
Indicates when a call is running over a wireless network rather than the mobile one, which is how you confirm the setting is doing anything.
A practical fallback. Its calls use the data connection, so they work in places the carrier voice path does not, whatever the settings say.
The same approach, and it can also place calls to ordinary telephone numbers, which is occasionally the one that gets a message through.
For a call that has to happen from a room with no usable mobile signal and a working wireless network.
What each feature costs
- Works with no mobile signal at all
- Calls are usually clearer over a decent connection
- No extra charge from most carriers
- Genuinely fixes basements and thick-walled buildings
- Only as good as the broadband behind it
- Handover to mobile as you leave can drop the call
- Emergency call location depends on a registered address
- Not offered on every plan or every handset variant
If both are on and calls are still poor, the remaining possibilities are worth working through in order: the wireless network itself, which a latency and packet loss test will settle; the building, which a call made standing outside will settle; and coverage at that address, which a coverage map and a conversation with the carrier will settle. A signal repeater or a carrier-supplied femtocell is the last resort, and worth asking about only once the free settings have been exhausted.
Turn on VoLTE and Wi-Fi calling, register the emergency address, and test from the room where calls fail. If the options are missing, it is the carrier, not the phone.
Frequently asked questions
Does Wi-Fi calling use my data allowance?
It uses the wireless connection, so it comes out of your broadband rather than your mobile data. Voice calls use very little in any case. Most carriers charge for them exactly as they would an ordinary call.
Why can I not find the setting on my phone?
Most often because the carrier has not provisioned it for your account, or because your handset variant is not on their approved list. Check for system and carrier updates first, then ask the carrier directly.
Will a call continue if I walk out of the house?
Sometimes. Handover from a wireless network to the mobile one is not seamless everywhere, and a call started indoors may drop at the door. Where calls are usually fine outside, setting the preference to the mobile network avoids it.
Is VoLTE worth turning on if my calls are fine?
Yes. It gives better voice quality, faster connection, and keeps data working during a call. In many places the older networks it would otherwise fall back to have already been switched off.
Read next
Nothing has infected your phone. Something you installed has permission, and the fix is a list in settings.
A phone will happily run a keyboard, a mouse and a memory stick. It will not power a desktop hard drive.
Hard and fast are different things. Almost every game confuses them, and these do not.
