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Instructions

Prevent roaming in Switzerland

There are three solutions. Each works on its own, you don't need all of them. Pick the one that suits you, then open your operating system.

I just don't want to use mobile dataOption A: switch off data roamingMy phone should not switch at allOption B: fix your network, also protects calls and SMSI have a Swiss data packOption C: use Data Saver

Menu names can differ by manufacturer and version. The screenshots show a Pixel running Android 17.

Android

Screenshots: Pixel, Android 17
A

Switch off data roaming

For everyone who does not want to use mobile data in the Swiss network. You do not have to choose the network yourself.

  1. Open Settings.
  2. Network & internet › SIMs, then tap your SIM.
  3. Switch off the Roaming toggle.
Android settings, Network & internet page with the SIMs entry
1. Network & internet
SIM details with the Roaming toggle switched off
2. Roaming off
Important: Calls and SMS remain possible and can still cost money in the Swiss network. If that matters to you, use option B.
B

Fix your network

Your phone stays on your German or Austrian network and does not switch secretly. This also protects calls and SMS.

  1. Network & internet › SIMs, tap your SIM and scroll down to the Network section.
  2. Automatically select network: switch it off. A list of networks opens and the phone searches for networks.
  3. Tap your network, for example “Telekom.de”. Skip Swisscom, Sunrise and Salt.
SIM details, Network section with the Automatically select network toggle
“Network” section
If your network is weak at your location, you will have no reception. Switch back to “Automatically select network” at home and abroad.
C

Use Data Saver

Only useful if you have booked a data pack for Switzerland. It stretches the small allowance.

  1. Network & internet › Data Saver: open it and switch on Use Data Saver.
  2. Also open Data warning & limit in the SIM details, switch on Set data limit and enter a value. The phone then cuts off data when the limit is reached.
Data Saver page with the toggle switched on
Data Saver
Data warning & limit page with the toggles for warning and limit
Data warning & limit
Data Saver stops some apps from sending or receiving data in the background. It is not a hard limit, only the data limit is.

iPhone

Screenshots to follow
A

Switch off data roaming

For everyone who does not want to use mobile data in the Swiss network. You do not have to choose the network yourself.

  1. Settings › Mobile Service (called Cellular in some regions). With two SIMs, choose the right one first.
  2. Mobile Data Options › Data Roaming: switch it off.
Important: Calls and SMS remain possible and can still cost money in the Swiss network. If that matters to you, use option B.
B

Fix your network

Your iPhone stays on your German or Austrian network and does not switch secretly. This also protects calls and SMS.

  1. Settings › Mobile Service › Network Selection
  2. Automatic: switch it off.
  3. Tap your network. Skip Swisscom, Sunrise and Salt.
If your network is weak at your location, you will have no reception. Switch back to “Automatic” at home and abroad.
C

Use Low Data Mode

Only useful if you have booked a data pack for Switzerland. It stretches the small allowance.

  1. Settings › Mobile Service › Mobile Data Options › Data Mode › Low Data Mode
This mode stops automatic updates, photo upload and background refresh. iOS has no hard data limit.

I have not yet checked the iPhone menu paths on a device; the screenshots will follow. Menu names vary by iOS version and region. If a menu is called something else on your phone, let us know.