When your iOS device evaluates service set identifiers (SSIDs) and determines which network to auto-join, it will try to connect to networks in this order:
- Your "most preferred" network
Known networks are scored based on your actions. If you manually switch to a network, its score increases. If you manually disconnect from a network, its score decreases. The "most preferred" network is the network with the highest score.
- A private network
Private networks are those set up in homes and offices and can include the Personal Hotspot on your iOS device. iOS reconnects to known private networks in order of most recently joined.
- A public network
Public networks are designed for general access in public places like a hotel, airport, or coffee shop. Some other examples include Hotspot 2.0, Passpoint, EAP-SIM, or Wi-Fi connections that are provided by cellular carriers and network access providers.
If iOS finds multiple private or public networks, iOS prioritizes networks by security level and chooses one based on the following order:
- Unsecured / Open
If iOS finds multiple networks of identical category and security level, it chooses the SSID with the strongest received signal strength indication (RSSI). Learn more about RSSI and wireless roaming for enterprise.
Unsecured / Open networks will not be auto-joined unless the network was connected to within the past two weeks.
About auto-joining after a restart
After a restart, iOS Wi-Fi credentials are available only after you unlock your device. iOS waits until after the device is unlocked before auto-joining any nearby network.