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Knowledge document #3337
FRITZ!Box 6890 LTE
This support document is available for the following products:

Throughput of the mobile connection is too low

The throughput displayed in the FRITZ!Box user interface for the mobile connection is significantly lower than the speed guaranteed by the mobile network provider.


  • The throughput of the mobile connection depends on factors such as the distance from the mobile station, the shielding effect of the walls of your own house, of neighboring houses, and also trees. Storms and other users located in the same radio cell can also reduce the throughput.

    Important:In many places, you will not be able to fully achieve the guaranteed throughput. This is why mobile network provider say that they offer speeds of "up to" a certain value.

Simply proceed as described below. After each measure, check whether the problem is solved.

Note:All instructions on configuration and settings given in this guide refer to the latest FRITZ!OS for the FRITZ!Box.

1 Using a different modem version

The software version for the FRITZ!Box's integrated mobile broadband modem undergoes constant development with each FRITZ!OS to ensure that it can establish optimal mobile connections under all circumstances. However, in rare cases the FRITZ!Box may be able to negotiate higher data rates with certain versions. Therefore, test the current and the previous modem version:

Using the latest FRITZ!OS

The modem version is part of FRITZ!OS. Make sure that the FRITZ!Box is using the latest FRITZ!OS and therefore the latest modem version:

  1. Install the latest FRITZ!OS on the FRITZ!Box.

Using the previous modem version

If the problem occurs with the latest modem version (for example after updating FRITZ!OS), test the modem version of the previous FRITZ!OS:

  1. Click "Internet" in the FRITZ!Box user interface.
  2. Click "LTE Information" in the "Internet" menu.
  3. Click on the "Reception" tab.
  4. Enable the option "Use previous software version for the integrated mobile network modem". If the option is not displayed, the FRITZ!Box model being used always uses the latest software version.
  5. Click "Apply setting" to save the settings.
  6. Now the FRITZ!Box enables the previous modem version and reinitializes the mobile network modem. Afterwards, the FRITZ!Box attempts to establish a mobile connection again.

2 Selecting the frequency band

If several frequency bands are available at your location, you may be able to increase the throughput of the mobile connection by selecting a specific frequency band:

Note:In Germany, the frequency bands 2.6 GHz, 1.8 GHz, and 800 MHz are used. Not all frequency bands are available at all locations, and not all mobile network providers support all frequency bands.

  1. Click "Internet" in the FRITZ!Box user interface.
  2. Click "Account Information" in the "Internet" menu.
  3. Click on the "Internet Connection" tab and then the "Mobile" tab.
  4. In the "LTE Frequency Band" section, enable the option "Manual" and disable all frequency bands except "2.6 GHz / band 7".
  5. Click "Apply" to save the settings.
  6. If the FRITZ!Box can establish a mobile connection using the frequency band you selected:
    1. Click "Internet" and then "LTE Information".
    2. Click on the "Mobile" tab.
    3. Check which speed is displayed in the "Throughput" line.
  7. Repeat steps 2 - 6 with the frequency bands "1.8 GHz / band 3" and "800 MHz / band 20", and use the frequency band the FRITZ!Box can achieve the highest throughput with.

3 Finding the ideal location for the FRITZ!Box

You can use the alignment aid to find the ideal location for the FRITZ!Box and the best position for the mobile network antennas:

  1. Click "Internet" in the FRITZ!Box user interface.
  2. Click "LTE Information" in the "Internet" menu.
  3. Click on the "Reception" tab.
  4. Click the "Start Alignment Aid" button.
    • Now the current signal strength of the antennas is displayed by the LEDs on the FRITZ!Box (in five levels) and in the user interface.
  5. Select a location for the FRITZ!Box where the signal strength is as high as possible. When doing so, note the following:
    1. Do not set up the FRITZ!Box in the corner of a room.
    2. Place the FRITZ!Box as close to an outside wall as possible. If you know where your provider's radio cell is located, place the FRITZ!Box by the wall facing the radio cell.
    3. Position the FRITZ!Box so that it is as unobstructed as possible, i.e. not directly in back of or under an obstacle such as pieces of furniture or a heater.

4 Connecting an outdoor antenna

If you are using the FRITZ!Box in the fringe area of the network coverage of your mobile network provider (outdoor coverage area) or in a building that exhibits a strong shielding effect, the two mobile network antennas included in the package may not be sufficient for optimal radio traffic. In this case, you can increase the transmission and reception power of the FRITZ!Box by using an outdoor antenna (for example on your balcony or mounted on your roof):

5 Contacting your provider

Your mobile network provider may have throttled the mobile connection if a particular data limit was exceeded, or your provider may be experiencing technical difficulties:

  1. Have your mobile network provider check your mobile connection.