You can choose a preferred Network through your phone's network settings. The problem with this is, even if you prefer 3G (WCDMA) it might fallback to 2G if the 3G network is temporarily poor. One way to force it to stay on 3G or 4G is, if your phone is Android, try calling *#*#4636#*#* This doesn't work on all phones but if you get a menu, choose Phone Information. Then scroll down and Set Preferred Network Type to WCDMA Only. If your phone/SIM supports 4G, you can choose LTE Only. But with LTE Only, you won't receive any calls. 4G needs to fallback to 3G (WCDMA) for voice calls. If you want to use LTE Only, you'll have to change the preferred Network back through the *#*#4636#*#* short code or through your phone's network settings when you're done.