Why does my phone keep dropping calls?

Dropped calls feel like a fault with the phone and usually are not. Four things can be responsible — coverage, the phone, the SIM, or the network itself — and they are distinguishable in a few minutes.

Step by step

1. Establish where it happens.Only at home or in one building points at coverage. Everywhere points at the handset, the SIM or the account. This single question rules out most of the possibilities.
2. Turn on wifi calling.Calls route over your broadband instead of the mobile network. It is free on all the major UK networks and it resolves poor indoor coverage completely. This is the single most effective fix and most people have never enabled it.
3. Check the network's coverage map and status page.Every operator publishes both. A mast fault or planned work in your area explains a sudden change that has nothing to do with your phone.
4. Restart the phone.It re-registers with the network from scratch. Unglamorous, and it genuinely resolves a proportion of intermittent registration problems.
5. Reseat or replace the SIM.Take it out, check for dirt or damage on the contacts, and refit it. An old SIM that has been moved between phones several times can develop poor contact. Replacements are free from the operator.
6. Try the SIM in another phone.If the problem follows the SIM, it is the SIM or the account. If it stays with the phone, it is the handset. This is the definitive test.
7. Check network mode settings.A phone locked to a single network generation, or with 5G behaving poorly at the edge of coverage, drops calls. Setting it to automatic, or temporarily to 4G, often stabilises things.
8. Turn VoLTE on.Calls over 4G rather than falling back to older networks. It is more robust in most areas, and some networks have retired the older networks it would otherwise drop to.
9. Check for a case or a grip blocking the antenna.A very thick or metallic case, or covering the lower part of the phone with a hand, degrades reception measurably. Worth testing without the case.
10. Update the phone and reset network settings.Carrier settings updates arrive with system updates. If nothing else works, resetting network settings clears the mobile configuration — note that it also clears saved wifi passwords.
11. Report it to the network with detail.Times, dates, locations and how often. They can check the masts serving that area, and a specific report gets a specific answer where a general complaint does not.
12. Consider a signal booster only as a last resort.Some networks supply approved femtocells for poor home coverage. Never buy an unapproved repeater — operating one is illegal in the UK and it interferes with the network.

Tips

• Wifi calling also means calls work in a basement, a lift with wifi, or anywhere with broadband and no signal. It is worth enabling even if calls are currently fine.
• If calls drop at a consistent point in a journey, that is a handover problem between masts and is worth reporting with the location.
• Test with a call to a landline. Calls to another mobile can drop because of the other end, which muddies the diagnosis.

Common mistakes

• Assuming it is the handset — Coverage, the SIM and the network account for more cases than the phone. Swapping the SIM into another phone settles it in two minutes.
• Buying an unapproved signal booster — Operating one is illegal in the UK and it interferes with the network for everyone nearby. Ask your operator for an approved femtocell instead.

If it doesn't work

Questions people ask