When the mobile network goes down: how to reach your family

What fails first

In a power cut, your home equipment stops first: the broadband router, the digital landline and cordless phones all need mains power. Then mobile masts run on their back-up batteries for a while. Be Ready says mobiles may stop if your local mast is affected, though some areas may keep working on back-up power.

In the 2025 Iberian blackout, a Spanish internet exchange reported that mobile data lasted about 2 hours and calls about 4. National TV and radio, network cores and the big data centres kept running. The same report notes its satellite phone was "completely useless", because every phone it could call was offline too.

The lesson: a plan agreed in advance beats any gadget.

Make a family plan (it takes 15 minutes)

1. One out-of-area contact. A relative or friend who lives elsewhere. Everyone messages that one person, who passes news on, so you're not all trying to reach each other at once.
2. Check-in times. For example, phones on for 5 minutes on the hour, then back to low-power or airplane mode.
3. Two meeting places. One close to home (a neighbour's, the end of the street) and one further away (a relative's, a library in the next area), in case the first isn't safe.
4. A no-contact rule. If you've heard nothing by a set time, go to meeting place one at fixed times, for example 12:00 and 18:00, and wait a set time.
5. Children at school. Check the school's own plan and make sure it has your current numbers.
6. Someone who lives alone. Agree that if you can't call, you or someone they trust will visit in person.

Write it on paper. Be Ready's checklist asks for a written list of important phone numbers, because phones die and contacts stored in the cloud may be unreachable.

Using a weak network well

These are general good practice, not official rules:

• Text, don't call. Short texts are small and often get through when calls fail. Messaging apps and email need mobile data, which went first in Iberia.
• Keep it short: who, where, OK or not, next check-in time.
• Don't keep redialling. It drains your battery and loads the network.
• Low-power mode on, screen brightness down, and wifi and Bluetooth off if there's nothing to connect to.
• Call 999 in an emergency. Don't rely on a text or social media to reach help.

Your landline: probably not a power-cut phone any more

Ofcom says digital landlines need mains electricity and won't work in a power cut unless there's a battery back-up. BT plans to retire its old analogue network by 31 January 2027.

If you rely on your landline because you have no working mobile or no reliable mobile signal at home, your provider must offer you a free back-up, such as a battery unit, lasting at least one hour. Some offer up to seven hours. Ask now, not during a storm. If anyone has a telecare alarm that uses the phone line, tell both the phone provider and the alarm company.

Citizens Advice says an old analogue phone plugged into an analogue line should still work, but most homes have already moved to digital.

Emergency Alerts

GOV.UK sends Emergency Alerts from mobile masts to compatible phones in an area at risk. They work on 4G and 5G, need no data or wifi, and need no sign-up. They won't reach a phone that's switched off, on 2G or 3G only, or wifi-only, and may not reach one in airplane mode. Once the local mast's batteries run out, alerts stop too, which is why a battery or wind-up radio matters: see choosing an emergency radio.

Walkie-talkies

Ofcom lists PMR446 walkie-talkies as licence-exempt. They suit a household, a block of flats or a street.

• Boxes often claim 10 km; that assumes open ground. In towns, expect a few hundred metres to a kilometre or two (general experience, not a tested figure). Height helps.
• Buy them in matched sets and give one to each person you'll need to reach.
• Agree a channel and a listening time in advance, and write both on your plan.
• Choose sets sold as licence-free PMR446. Cheap handhelds with screw-off aerials are often not PMR446 sets, and transmitting on them needs an amateur licence.

People who need extra help

Ofgem's Priority Services Register gives priority support in an emergency and advance notice of planned power cuts where possible. People over state pension age, families with young children, and anyone with a disability, long-term condition or medical equipment can usually join. Contact each energy company and your water company separately.

Keep the phones charged

A charged power bank per phone is the simplest step. See how to keep your phone charged in a power cut.

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Related guides

• Staying in touch when networks fail
• The digital landline switch: will your phone work in a power cut?
• UK Emergency Alerts: a calm guide
• Broadband and phone outages: what to do, and how to prepare
• Emergency contacts list template (UK)
• Priority Services Register: a plain guide

Free tools

• Priority Services Register checker
• Storm tracker: live Met Office warnings

We're an independent UK site, not the government. We check guides against official sources and link to them. In an emergency call 999.

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