Your Mac remembers every Wi-Fi network it has joined

What it keeps

For each network, macOS keeps its name, its security type and when it was added. It also notes when the network was last joined, by you or automatically. The password goes in your keychain. The dates are in /Library/Preferences/com.apple.wifi.known-networks.plist, which only an administrator can read.

With iCloud Keychain turned on, the list and the passwords are shared with your iPhone, iPad and other Macs, so a network joined on one is known to all of them.

Why it matters

Network names are often places: a hotel, a hospital, an office, a school, or a home with the family's name on it. Anyone who uses your Mac can open the list, and it goes with the Mac if you sell or pass it on without erasing it. Most of the networks are ones you'll never join again.

See it yourself

Open System Settings > Wi-Fi and click Advanced. The Known Networks list shows them all.

In Terminal, find your Wi-Fi device's name (usually en0):

networksetup -listallhardwareports

Then list the networks, in the order your Mac prefers them:

networksetup -listpreferredwirelessnetworks en0

To see when each was last joined, with an administrator's password:

sudo plutil -p /Library/Preferences/com.apple.wifi.known-networks.plist | grep -E '"wifi.network|Joined'

Clear it yourself

In System Settings > Wi-Fi > Advanced, click the menu button next to a network and choose Remove From List. Or in Terminal, with an administrator's password:

sudo networksetup -removepreferredwirelessnetwork en0 "Network Name"

Removing a network also forgets its password, so keep the ones you still use, such as home and work. With iCloud Keychain, check your iPhone and iPad afterwards too: Settings > Wi-Fi > Edit shows their list.

The easier way

TrailSift's free audit counts the networks your Mac remembers. Its Wi-Fi Networks page lists them by name, with when each was last joined once you approve reading the dates. TrailSift Pro forgets the ones you choose, all at once, leaving the networks you still use.

Updated 14 October 2026. More guides: all TrailSift guides.