How to See Who’s Using Your Wi-Fi
If you suspect someone is using your Wi-Fi network without permission, but you aren’t 100% sure, you can usually log into your router’s interface and check a list of connected devices. Exactly how you log in and check will vary by device manufacturer, so consult your router’s documentation.
Once you see a list, look for unfamiliar names in the list of actively connected devices. Those might be devices used by your neighbors. Some routers let you kick, block, or ban devices directly from this list by blocking a particular MAC address. This blocking works in a pinch, but it isn’t foolproof because some devices such as iPhones provide new, random MAC addresses as a privacy measure. That means the device might not be blocked anymore the next time they connect.
Also, be aware that not all your Wi-Fi devices will have clear and obvious labels. If that’s the case, make sure you compare the MAC addresses of the unknown devices in your list with the MAC addresses of the devices you own before doing any banning or blocking. Otherwise, you might accidentally block an important device in your household.
Short Term: Unplug Your Router or Modem
If you need someone to stop using your Wi-Fi immediately—as in right this second—locate your router and unplug it from its power source. It will turn off, and no one will be able to connect to it.
If you want to be able to configure your router while preventing access to the internet temporarily, you could instead leave your router plugged in but unplug your cable or DSL modem (if you have one). Once you’ve made the changes we’ve recommended below, you can plug the modem back in, and the bandwidth thieves will be locked out.
Turn Off Open Wi-Fi Access
If you’re running an open Wi-Fi access point that allows people to connect without a password, it might be time to rethink hosting an open network. If someone using your internet connection does something illegal online, it could bring you trouble or compromise your data security.
To fix this, you’ll need to log in to your router’s configuration interface and enable encryption (such as WPA2 Personal—or better yet, WPA3 Personal, if available) and a connection password. After configuring a strong Wi-Fi connection password, don’t give it to your neighbors. You will have to enter it on all the devices you want to connect.
Use a Modern Encryption Standard
Older Wi-Fi encryption methods such as WEP, WPA1, and WPA2-TKIP are considered insecure. WEP in particular is easy to hack using brute force methods. So if you’re still using one of those, it’s time to change to a more secure encryption method. We recommend using WPA2-Personal (or WPA3-Personal if it’s available).
Using good, modern encryption standard will keep out potential nearby hackers and prevent possible eavesdropping on your internet activities by neighbors. Also, disable WPS (Wi-Fi Protected Setup), which is also insecure and might provide a point of entry for a hacking-savvy neighbor.
If your router doesn’t support newer encryption methods, it’s definitely time to upgrade your router.
Disable Your Router’s Guest Account
Many Wi-Fi routers support guest accounts that are isolated from your main local area network (LAN), use an alternate password, and can be subject to other restrictions.
If a neighbor is stealing Wi-Fi through a guest account, then you’ll need to log into your router’s configuration interface and disable it.
Even if your neighbors aren’t using a guest account for access, you should probably disable your guest account anyway if you never use it. They are often not secure.
Change Your Wi-Fi Password
There may have been a time when a neighbor visited and you gave them your Wi-Fi password, and they just keep using your internet even when they’re not visiting. Or maybe a trusted neighbor or family member nearby gave your Wi-Fi password out to a friend.
If that becomes a problem, it’s time to change your Wi-Fi password. To do so, you’ll need to log in to your router’s interface. Look for settings labeled something like “Wi-Fi Setup.” Somewhere near the SSID, you’ll see a space to input a new password. Choose a secure password, and apply the changes to your router, rebooting it if necessary.
When the router comes back online, you’ll need to enter this new password into the computers and devices that connect via Wi-Fi at your location. This could include smartphones, tablets, game consoles, TV sets, smart home devices, and more. Obviously, keep this new password private to prevent others from using your Wi-Fi without permission.
Managing the Social Ramifications
If you’ve previously given out your Wi-Fi password to a neighbor and you change it, they might ask you later for the new password. If you have a good relationship, you might tell them you’ve decided to limit access to your internet to members of the household only from now on. No further explanation is necessary.
Remember to set firm boundaries and stick to them. If they’re aiming to be good neighbors, they will respect your wishes. If you pay for your internet connection, you have the right to control who uses it without any further justification. Obviously, there may be other sensitivities at play, so your own judgement is best. Good luck!