How to Reach Family After a Disaster When the Network Is Down

Direct answer: after a large disaster, send a short text message rather than calling, try once and wait, and use an agreed out-of-area contact as the family's message relay. Voice calls need a continuous circuit and fail first under congestion; a text is a few hundred bytes that will queue and deliver when a gap appears.

Why the phone network fails, and how

A mobile network is built for ordinary demand, not for everyone in a city calling at the same second. When a large event happens, three separate things break, usually in this order:

• Congestion. The radio access network runs out of channels. Nothing is damaged; there is simply no room. This is the commonest reason your call does not connect, and it can happen hundreds of kilometres from the event, on your own side.
• Power. Cell sites have batteries measured in hours, not days. As those drain, coverage shrinks site by site. This is why the network often works for the first evening and is worse the next morning.
• Backhaul. The fibre or microwave link joining a tower to the core network is cut. Coverage bars can look normal while nothing gets through.

The important consequence: bars on your screen do not mean the network can carry your call. A phone showing full signal can be attached to a tower with no working path onward.

Text, do not call

Emergency management agencies worldwide give the same advice, and it is not about politeness. A voice call holds a dedicated channel for its whole duration. An SMS is a tiny burst that rides on signalling capacity and will be stored and retried by the network for hours if it cannot be delivered now. In a congested cell, texts routinely get through when no call will connect.

The same logic favours the low-bandwidth end of every app. A one-line message on WhatsApp, Signal or Telegram will often send on a connection far too weak to hold a voice call, and far too weak to load a photo. Send words first. Photographs and voice notes can wait.

Do not redial repeatedly

This is the hardest instruction to follow and the most important. Every failed attempt still consumes signalling capacity before it fails. Twenty people redialling every ten seconds can hold a cell in permanent overload, so the redialling itself is part of why nobody is getting through — including the person you are trying to reach, who may be trying to call out.

Try once. Send a text. Wait. Try again in fifteen minutes.

The out-of-area contact

The oldest piece of family emergency planning is still the best, and almost nobody has it set up before they need it.

Agree in advance on one relative or friend who lives far away — a different city, ideally a different country. Everyone in the family contacts that person rather than each other. Local networks are congested; a call or message to somewhere unaffected usually is not. The out-of-area contact holds the picture and relays it, so five people are not each making five calls into a broken network.

Write the number on paper as well as in your phone. Very few people can recall a family member's number from memory any more, and a phone with a dead battery is the commonest way a plan fails.

Agree on a single word

Decide now what "I am fine" looks like, so it can be sent in three seconds with one thumb on a failing connection. A single agreed word — SAFE, or THEEK, or whatever your family actually says — carries everything that matters and costs nothing to transmit.

Add the location if it is not obvious, because "safe" without a place forces a follow-up: SAFE — at Ammi's.

Official channels for tracing people

• ICRC Restoring Family Links — the International Committee of the Red Cross and national Red Cross and Red Crescent societies run the long-standing service for people separated by disaster and conflict, at familylinks.icrc.org. It works on a timescale of days and weeks rather than hours, and it is the right route when someone remains unreachable.
• National disaster management authorities often open helplines and registration numbers within a day of a major event. These are announced on the agency's own channels; the emergency contacts for 145 countries are listed on this site and inside the app.
• Platform safety features — some large platforms activate a "mark yourself safe" feature for major disasters. Useful when it is switched on, absent when it is not, and never something to rely on.

Person-finder databases have historically been activated by technology companies for very large disasters. Treat any of them as a bonus, not a plan.

What to do before anything happens

• Set the out-of-area contact and make sure every family member has the number, on paper.
• Agree the one-word message and who sends it to whom.
• Keep a power bank charged. The phone that matters is the one still on at hour thirty.
• Know the local emergency number for the place your family lives, not just for the place you live. They are rarely the same, and they are listed on this site's country pages.
• Turn on cell broadcast alerts on the phones of people who live in the affected area. Most countries now use them, and they arrive even when the network cannot carry a call.

What this site can and cannot tell you

This site aggregates public feeds from official agencies. It can tell you that a magnitude 6.4 earthquake was recorded near a place you are watching, and roughly when. It cannot tell you whether a specific person is alright, and it is not an official warning system. Nothing here replaces instructions from the local authorities where your family lives.

Absence of an event on this site means nothing reached the feeds we read. It does not mean nothing happened.

Related: the 72-hour emergency kit, how earthquake early warning works, and the earthquake safety guide.

Frequently asked questions

Why do text messages work when calls do not?

A voice call reserves a dedicated channel for its whole duration, so it fails as soon as a congested cell runs out of channels. An SMS is a few hundred bytes carried on signalling capacity, and the network stores and retries it for hours, so it will often deliver during a brief gap in congestion.

Does redialling improve my chances?

No, and it makes things worse. Every failed attempt still consumes capacity before it fails, so mass redialling can hold a cell in permanent overload — including for the person you are calling, who may be trying to call out. Try once, send a text, then wait.

What is an out-of-area contact?

A relative or friend who lives far from the affected area, ideally in another country, whom everyone in the family contacts instead of each other. Local networks are congested while distant ones usually are not, so one relay replaces dozens of failing local calls.

My phone shows full signal but nothing sends. Why?

Signal bars only show the link between your phone and the nearest tower. If that tower has lost its backhaul connection to the core network, or the network beyond it is saturated, the bars stay full while nothing gets through.

How do I trace someone who stays unreachable?

Use the ICRC and national Red Cross or Red Crescent Restoring Family Links service at familylinks.icrc.org, and any registration line opened by the national disaster management authority. These work over days rather than hours, which is the realistic timescale once ordinary contact has failed.

Sources

• Ready.gov — Family Communication Plan
• FEMA — Emergency Communications
• ICRC — Restoring Family Links
• IFRC — Disaster preparedness
• GSMA — Mobile networks in emergencies
• ITU — Emergency telecommunications

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