How to tell if someone is stealing your WiFi

What are the signs your WiFi has been stolen?

If you notice any of the following, it could be a sign that neighbours, or even passers-by, are using your WiFi:

A sudden slowdown in internet speed – it takes ages to stream a video or load a web page

Frequent downtime – you keep losing your internet connection

The lights on your router are constantly blinking, even when you're not using any of your devices

Your password won't work. It's a very extreme case, but a hijacker could change your password and lock you out of your own network

You have a capped data plan, but notice extra charges on your monthly bill

What should you do if you suspect your WiFi has been hijacked?

Aside from interrogating your neighbours (not advised), there are a couple of ways you can find out for sure whether your internet has been stolen:

Check your router’s device list

Start by logging into your router’s administration page. You should be able to do this by entering the IP address of your router into a web browser window.

In your admin dashboard, go to the section that lists all the Media Access Control (MAC) addresses connected to your WiFi. Not all routers are the same, but you can expect to find it under something like devices, wireless status or in the Dynamic Host Configuration Protocol (DHCP) client list.

Once you have your list of connected devices, identify the ones that belong to you. If you can’t make head nor tail of the list, either turn off each gadget one by one or simply disable the device’s WiFi to see what you’re left with. Then you’ll have your culprit. It’s all about playing detective.

Download a WiFi security app

Alternatively, you can download an app that will automatically search for unusual devices logged into your WiFi network and monitor it for suspicious activity. Some apps on the market show android users how many devices are on their router and others enable iOS users to see their connected devices.

How do you remove strangers from your WiFi?

If you think that someone who shouldn’t be is using your WiFi, there’s action you can take to put a stop to it.

The best thing to do is change your password, especially if you still use the default router name and password, as changing it will automatically boot everyone off your network – including you, of course. You can do this from the admin page on your router.

In most cases, a newer, more robust password will be enough to deter outsiders from stealing your WiFi. You, and everyone who lives with you, will have to add the new password to all your devices, but it’s worth the hassle to get rid of WiFi thieves.

Another way to block online intruders is by accessing the MAC filtering or device filtering option on your router admin page. Through this you can add MAC addresses you don’t recognise to a list of blocked devices. It’s worth knowing though, that this merely acts as a sticking plaster rather than a cure as hackers can use different MAC addresses to access your WiFi.

What are the risks of WiFi theft?

You may be understandably peeved if your neighbour is piggy-backing your WiFi, especially if you’re paying extra charges on a capped plan.

But the security risks pose a far greater threat. If someone is stealing your WiFi, you’re more vulnerable to identity fraud, as they could gain access to your personal data.

What’s more, if anyone has been using your WiFi network to conduct fraudulent and illegal activities online, then you’re responsible.

Cybercrime isn’t just the stuff of movies, it’s a very real danger – as shown by the latest Crime Survey for England and Wales:

• In the year ending March 2019, 54% of all fraud incidents were related to cyber crime

• It was estimated there were as many as 1 million cases of computer misuse, including hacking and malware attacks, 21% of computer virus incidents resulted in access to files or data being lost, while demands for money to return files were made in 12% of cases

• Victims of computer misuse were emotionally affected in 68% of incidents

How can you protect your WiFi from hackers?

Whether it's the cheeky neighbours pinching a bit of your broadband, or the more sinister and sophisticated hackers, here are some steps you can take to secure your WiFi network:

• Change your default network name (Service Set Identifier - SSID) to a random network name, not something like ‘Doug’s home WiFi’ that can easily identify you personally

• Change the password for your pre-shared network key. The longer the length, the more difficult it is to crack – aim for between 25-64 characters including capitals, numbers and/or special characters

• Turn on WPA2-PSK encryption on your router. You’ll find it in the wireless section of the admin page

• Position your router in the middle of your home to prevent your WiFi being accessible from outside

• Turn off your WiFi when you’re away from home. Avoid turning off your router overnight when you’re at home because disconnecting it repeatedly could hamper your broadband speed

• Enable your router’s built-in firewall

• Make sure all your devices are updated with the most recent software and have antivirus software

Be vigilant – be wary of clicking on pop-ups and antivirus messages from unknown sources. Check that any website you visit is encrypted. You’ll see a green padlock in the address bar, and ‘https’ at the beginning of the URL