If you see the message "Carrier Settings Update" pop up on your iPhone, you may be puzzled what it means and what you need to do about it, if anything. We'll explain all you need to know here.
This pop-up is Apple's way of alerting you that Apple or your wireless carrier (e.g., AT&T, Verizon, etc.) has made some kind of changes in how your iPhone connects to your wireless carrier's network, and that your device needs to be updated to accommodate these changes.
The "Carrier Settings Update" message is specific to iPhones and other Apple devices. Certainly there are carrier-related changes that affect Androids and other non-Apple devices, but companies such as Microsoft and Google include any updates related to these changes in more general maintenance or software updates.
As noted, your iPhone's carrier settings need to be updated because there has been some change in how your phone interfaces with your carrier. Any such changes can be presumed to have happened for a reason—perhaps the changes enable iPhones to connect with the network more efficiently, or introduce new capabilities like Wi-Fi calling, or fix various bugs or glitches. If you don't accept the updates you will forego any such improvements.
You also may see the notification that the carrier settings need to be updated the first time you turn your iPhone on after changing the SIM card.
Updating your iPhone with the new settings is as simple as tapping Update when the "Carrier Settings Update" notification pops up. Unlike with some updates, there is no need to restart your device for the changes to take effect.
The carrier settings updates are typically small, so the updating process should be brief.
If you instead tap Not Now" the "Carrier Settings Update" message will normally reappear once a day on your device until you accept the update.
The notification that your carrier settings need to be updated generally is issued promptly as soon as any such update is available, but if you prefer not to passively wait for the pop-up, it's possible to check for yourself.
Simply tap Settings on your iPhone, then General, and then About. If an update is available, the "Carrier Settings Update" message should pop up within 15-30 seconds. If you don't see that pop-up, then it's safe to assume there is no update available.
If you do generate that pop-up, you then accept the update the same way you would if it had popped up on its own—that is, by tapping "Update."
What if you accepted the update, or think you did, but you want to make sure it "took"? What you can do is turn off your iPhone, wait at least 30 seconds, and then turn it back on. As described above, choose Settings, then General, and then About. If the "Carrier Settings Update" notification doesn't pop up, you're good to go!
