Communication outage

Impact of power outages and domestic roaming during a crisis How to prepare for a communication outage?How to call emergency services (112) without signal?Domestic roaming

Communication services can be interrupted mainly due to power outages or large-scale cyberattacks.

Communication services are generally divided into three categories:

Telephone service – making and receiving landline calls.
Mobile phone service – making and receiving calls regardless of location, and sending/receiving text messages (SMS or Short Message Service).
Data service – transmitting data based on your contract with the provider, e.g. browsing news, TV services, etc.

For example, if your neighbourhood loses power, fixed internet (cable or fibre) will stop immediately because home Wi-Fi devices require electricity. If your mobile, landline, internet, and TV services all come from the same provider, be prepared for simultaneous disruption.

Impact of power outages and domestic roaming during a crisis

Short-term and local outages usually don’t significantly affect communication services. In some areas, mobile signal may weaken. If this is the case go outside where the signal is better. If nearby areas have power, move there. It's likely that there will be mobile signal there as well.
Widespread and long-term outages gradually reduce access to communication services. Providers prioritise maintaining service in local government centres using generators.
In a state of emergency or wartime, the government may activate domestic roaming, allowing you to use other operators’ mobile networks. Service quality may vary but should be sufficient for sending messages and reading news. The public will be informed when this type of roaming is activated.

How to prepare for a communication outage?

Write down important phone numbers (family members, neighbours, 112 – Emergency Response Centre, 1247 – State Help Line, local authority info line, etc.). If your phone battery dies or contact list is inaccessible, you can call loved ones using someone else's phone.
Landline phones and Wi-Fi routers do not work during a power outage.
Subscribe to mobile internet – it works as long as the network has backup power and your device battery lasts. In widespread outages, data services may be slow or limited. Avoid unnecessary mobile calls; use communication only when essential.
If signal is poor, go outside or to higher ground. In very poor conditions (e.g. during large events), prefer text messages (SMS) over calling.
Acquire a radio powered by batteries, dynamo, or solar energy. You can also listen to news via your car radio.
Keep a power bank and spare batteries to charge your phone when needed. Ensure power banks are always charged.
Learn how to watch free-to-air TV channels, e.g. using an indoor or rooftop antenna.
Know where to get help in an emergency – nearest resilience centre, fire station, police station, or emergency medical department.
Keep cash at home, as mobile payments and bank cards may not work during data outages. This includes apps requiring identity verification (e.g. Mobile-ID, Smart-ID).
Agree on a meeting point with your family in case you cannot reach each other.

Mother and a child listening to FM radio

What to do if communication is lost

Turn off battery-draining features on your smart device: Wi-Fi, mobile data, apps needing connectivity, screen brightness, Bluetooth, etc.
Listen to hourly news updates on the radio – car radios also work.
Be aware that data outages may affect card payments and electronic identification (Mobile-ID, Smart-ID).
You can still call 112 even with limited connectivity – your phone will automatically use any available mobile network, even if it’s not your provider.
If no communication is possible and you need urgent help, go to the nearest fire station, police station, or emergency medical department.
Seek information from your community, resilience centre, fire station, or police station.
If there’s no signal, move to higher ground or an area unaffected by the power outage.

How to call emergency services (112) without signal?

Make your SIM card inactive:

On a button phone: remove the SIM card and dial 112.
On a smartphone: restart the device, skip entering the SIM PIN, and dial 112.
On newer smartphones: hold down the power button to access emergency call options.

After the call, reactivate your SIM card so the emergency dispatcher can call you back if needed.

Domestic roaming

During an emergency or war situation, the state may activate domestic roaming, which would allow the use of the mobile networks of other operators. The quality of service may vary but is sufficient for getting information (sending messages, reading the news). The activation of roaming will be announced publicly.

After the activation of domestic roaming, it might be necessary to manually select another operator’s network on your phone.

To select a network, open the phone’s settings and search for the possibility to select a network under mobile or network settings. Switch off automatic network selection and choose another operator’s network from the list. If it does not connect immediately, switching Airplane Mode on and off or restarting the phone might help.

If the chosen network is not operational, select another network from the list. It might take some time to find a network.

Once it has been announced that domestic roaming has ended, you should return your phone to your regular network. Open the network settings on your phone again and switch on automatic network selection or select your regular operator’s network manually. In necessary, restart your phone.

If a network has been chosen manually, it may stop the phone from automatically moving into the network with the best signal.

How to manually select a network?

The instructions may differ depending on the phone but generally you can find the possibility to manually select a network as follows:

iPhone

Settings → Mobile Service → Network Selection → turn off automatic network selection → wait until the device displays possible networks and select a new network.

Samsung Android

Settings → Connections → Mobile Networks → Network Operators → turn off Select Automatically → wait until the device displays possible networks and select a new network.

OnePlus Android

Settings → Mobile Network → if there are two SIM-cards in the phone, select the SIM-card for which you want to change the network → Operator → turn off Auto-select → the system gives a warning that the connection could be lost → Off / Cancel Auto-select → wait until the device displays possible networks and select a new network.

Xiaomi Android

Settings → Network Settings → SIM Cards & Mobile Networks → if there are two SIM-cards in the phone, select the SIM-card for which you want to change the network → Mobile Networks → turn off Automatically Select Network → the system gives a warning that the connection could be lost → press Next and then OK → wait until the device displays possible networks and select a new network.

Sony Android

Settings → Network & Internet → Mobile Networks → turn off Automatically Select Network → wait until the device displays possible networks and select a new network.