Yes, AT&T is maintaining the 3G/UMTS and 4G/LTE networks while upgrading to 5G . Your 6S will continue to operate on 3G and 4G. The current plan is to take down 3G in 2022 but 4G will still be in place after that.
Read moreIs iPhone 6S a 4G or 5G?
The iPhone 6 and 6 Plus are both 4G capable devices . If the mobile internet connection is 4G rated, the handset will show this next to the signal indicator in the top left-hand corner of the display. 3G, E or GPRS may also be displayed, but these represent a slower connection speed, dependent on location.
Read moreWhich iPhone does support 5G?
So, basically, any iPhone 12 or iPhone 13 model supports 5G. You won’t be able to access 5G with any of the previous models, even if you have a network provider that supports 5G. In order to have 5G, you’ll need an iPhone 12 or iPhone 13 model.
Read moreHow do I turn on my 5G on my iPhone 6?
Go to Settings > Cellular > Cellular Data Options . If you see this screen, your device has 5G activated. If you don’t see this screen, contact your carrier to confirm that your plan supports 5G.17 Mar 2022
Read moreIs iPhone 6s 5G ready?
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.
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