Why is my mobile broadband slow?

Mobile broadband speeds can vary depending on signal strength, network congestion, device capability, and router placement. Because mobile broadband uses a shared mobile network, speeds may fluctuate throughout the day. Simple steps like restarting your router or improving signal placement can often improve performance.

Common reasons for slow mobile broadband

1. Network congestion
Mobile networks are shared. If many people in your area are using the network at the same time — particularly during evenings or weekends — speeds may slow down. This is more common in busy or densely populated areas.

2. Weak signal strength
A weak mobile signal will significantly affect performance.

Things that can reduce signal include:

  • Thick walls
  • Metal structures
  • Basements
  • Distance from the nearest mobile mast

What you can try:

  • Move your router to a higher position
  • Place it near a window
  • Keep it away from thick walls

3. 4G vs 5G coverage
If your device switches between 5G and 4G, speeds may vary depending on coverage. Some areas have strong 4G coverage but limited 5G availability.

4. Router placement
Where you place your SIM router can have a big impact on speeds.

For best performance place your router:

  • Near a window
  • Away from thick walls
  • Away from other electronic devices that may cause interference

5. Data allowance or traffic management
If you are on a limited data plan and have used most of your allowance, speeds may be reduced. Some mobile networks may also manage traffic during peak usage times.

6. Device or router limitations
Older routers or devices may not support the latest network technologies such as newer mobile bands, carrier aggregation, or 5G connectivity.

7. Temporary network issues
Occasionally slow speeds can be caused by local mast maintenance, temporary network faults, or network upgrades in your area.

Steps you can try

  1. Restart your router or device
  2. Move your router to a better location (such as near a window)
  3. Check signal strength on your device
  4. Reduce the number of devices using the connection
  5. Test speeds at different times of the day