Check Low Data Mode When an iOS 27 Update Is Stuck

If an iOS 27 update is stuck, check the network before assuming that Low Data Mode is the cause. Apple documents several verified update blockers, including a missing internet connection, insufficient storage, an incompatible device, and trouble reaching the update server.

Check the network first

1. Connect to a reliable Wi-Fi network and avoid other large downloads while the update downloads.
2. Open the Wi-Fi network details and review Low Data Mode if it is enabled; turn it off temporarily only if you are comfortable with the network using more data.
3. Disconnect any VPN or proxy, then return to Settings > General > Software Update.

Rule out the other common blockers

Keep the iPhone connected to power, confirm that it has enough available storage, and check that the model supports the available update. If the alert says that Wi-Fi is required, change to Wi-Fi or use a computer update path rather than relying on cellular data.

Retry the download safely

If the download repeatedly stalls, Apple documents deleting the downloaded update from Settings > General > iPhone Storage and downloading it again. If that does not help, try another network or use Finder, Apple Devices, or iTunes on a computer. Keep a current backup before escalating to any recovery action.