iPhone keeps using data when on WiFi network

Hi @KingJHB,

Thank you for reaching out. We want to take a closer look.

Concerning your iPhone using cellular instead of Wi-Fi data, sometimes this happens when the Wi-Fi connection is not strong enough and the device preferably uses the stronger cellular data.

However, we'd like to probe more into this. Please let us know:

• how often does this happen
• how long has this been going on
• did you try to turn off your cellular data to see if the device uses Wi-Fi 

Let us know so we can assist further.

Doyin, AT&T Community Specialist.

Check all of your settings. Make sure WiFi assist is turned off and if necessary, restrict apps from using cellular data. Your phone will use whatever data path works best, if you let it. You totally control it. The only way to totally stop cellular data use is to turn cellular data off or put the phone in airplane mode.

How do you know if it's using cellular data when connected to your Wi-Fi network and not when it's NOT connected to wifi?

    Your phone has its own data meter which is a live record of the data being used.   AT&T's record is not live, but delayed by up to 72 hours.    Cellular carriers collect data and report back in three hour intervals and post on your account usage details.  But usage posted on your account usage details at noon may have been for usage over the past 3 hours or up to 72 hours prior to the posting.  

This is also why your bill is posted 4 days after the closing of your bill cycle in order to include all data you used within your bill cycle as accurately as possible. 

It's not impossible that your phone has a defective Wi-Fi antenna or that your home internet service is poor and therefore your phone is choosing the better connection which is cellular. If either of these is the case the way to force and test it is to turn off cellular data.   

   If after disabling cellular your phone has a hard time loading web pages and is constantly buffering, you then know that something is wrong with either the phone's Wi-Fi antenna or your home Wi-Fi service.