Go to Settings > Mobile > Mobile Data Options . If you see this screen, your device has 5G activated. If you can’t see this screen, contact your network provider to confirm that your plan supports 5G. Turn on Airplane Mode and then turn it off.
Read moreCan you cut 5G off on iPhone 12?
It uses what Apple calls “Smart Data mode” that tries to automatically strike the best balance between 5G/LTE and battery life. … However, inside the cellular settings, you can choose to turn 5G on/off on iPhone 12 manually to optimize for speed or battery life.
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