In Luxembourg:
- You must have a Tango Smart or Tango K.O. subscription
- You must have a VoLTE-compatible smartphone with the latest software update installed
- Your contact must also have a VoLTE-compatible smartphone and be a Tango customer
- You and your contact must be connected to the Tango 4G network

If you meet all these conditions, when you make your call, it will automatically switch to VoLTE.

Calling a contact who is with another operator:
To take advantage of VoLTE calls via 4G, your contact must have a Tango Smart or Tango K.O. subscription. If he or she is with another operator, the call will not be conducted in VoLTE even if calling in VoLTE has been activated.

Calls from abroad:
Currently, it is not possible to make calls in VoLTE via 4G from abroad. For Tango customers, this service is only available on a Tango 4G network in Luxembourg.

Calls to numbers abroad:
Currently, it is not possible to benefit from the VoLTE advantages when calling numbers abroad