Enable NB-IOT and LTE-M at the same time

Dear All,

I am building an application that needs to use NB-IOT and if that is not available then use LTE-M.

I tried sending this AT Command:


But this returns an error.

What I noticed is that if I enable both NB and LTE-M this command returns ERROR.

So I would like to ask if there is any way to achieve the following behaviour:

Check for NB-IOT network and if there is no connection to such network turn to LTE-M

Thank you all.

  • Hi.

    At the moment, only one LTE mode is supported at the time. See this note from the AT command documentation:

    Note: Only one supported LTE mode allowed at a time. This command is allowed only before activating the modem using the CFUN=1 command. If the mode needs to be changed, the modem must first be set to flight mode using the CFUN=4 command.

    However, the lte_lc driver will by default switch mode if it is not able to establish a connection. You can control this behavior with the CONFIG_LTE_NETWORK_USE_FALLBACK and LTE_NETWORK_TIMEOUT configuration options.

    Best regards,


  • Hello Didrik :)

    I'm also considering using both the NB_IOT and LTE-M capabilities of the nRF9160 at the same time. It can be something like LTE-M active until I meet a wall the signal doesn't pass through for example, then switch to NB_IOT, or simply like the example above where I will use the option with available network . Does the NRF9160 support both modes at the same time?  



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