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What is Kill Switch and what VPN services support it?

Kill Switch is very important if you use a VPN to ensure privacy and data protection. Without this feature, you cannot provide 100% security, even if you use the best VPN apps.

Table of contents:Kill Switch VPN logo

Virtual Private Network technology packs all the device’s traffic into a virtual channel and routes it to the VPN server, where a connection with the visited resource is already established.

But there are two serious non-obvious problems

  1. If the VPN channel is broken, the traffic will go in the usual unprotected way
  2. In reality, not all traffic is intercepted and protected.

Fortunately, good service VPN software provides effective user protection in all conditions and protects against both problems.

This is a list of VPN services that have kill switch:
  1. ExpressVPN: One of the first VPNs that use traffic blocking when breaking a secure connection. True, it’s called ExpressVPN not Kill Switch, but “Stop all internet traffic if the VPN disconnects unexpectedly”. The service is distinguished by the best combination of features, speed, and degree of privacy protection.
  2. NordVPN: It has two varieties of Kill Switch at once - the classic one, blocking traffic, and the progressive one, crashing protected apps. NordVPN is also one of the best VPN providers in 2022.
  3. Surfshark: Effective connection protection at the lowest price. At the same time, the characteristics of Surfshark are in many respects not inferior to ExpressVPN and NordVPN.
  4. CyberGhost VPN: Has a stable working Kill Switch. With this service, you will never forget to activate protection. The disadvantage is that Windows noticeably loads the system.
  5. PIA: A good choice for advanced users and professionals. It allows the user to configure any parameters of the VPN channel.

What is the Kill Switch?

Kill Switch is a function that prevents leakage of insecure data when going through the VPN channel. It works when the connection of the VPN server is lost and the transfer of all data is blocked, including web traffic, program and app data, DNS packets (transfer of addresses of visited sites), and any other information.

There are the following modifications of the Kill Switch:

  • Classic (described above). It only blocks traffic when the VPN unexpectedly disconnects.
  • Full. It blocks traffic even when manually disconnecting from the VPN.
  • Advanced. Non-standard methods of protection are applied. Most often, this is an instant shutdown of the protected app.

If the service claims to support Kill Switch, then this doesn't mean that it is available on all devices. Many services implement it only on some platforms. The most common protection in Windows apps. Least of all - iOS.

It’s difficult to find out what OS supports Kill Switch. Services never publish this information. It’s much easier to use a ready-made list of VPN services that support Kill Switch on all platforms.

3 important reasons to use Kill Switch 

It is important to know not only the obvious advantages of VPN with Kill Switch but also some non-obvious benefits of its use:

  1. Protection during continuous activity. Such activities include torrenting, streaming video, Skype and other VoIP telephony, file downloading, and more.  
  2. VPNs with disabled Kill Switch don’t protected 100% of the traffic. I came to this conclusion in 2019, having conducted a series of research of VPN services with support for blocking connections:

Active connections that are not protected by VPN are highlighted in red. Read more in the Avast SecureLine VPN review.

When protection was activated, the problem immediately disappeared.

3. Improving the protection of mobile devices. I have repeatedly mentioned some unexpected disconnects. In what cases can it happen?

I suppose the failure of the Internet service provider came to your mind first. This is partly true. But some situations occur hundreds of times more often!

Namely, automatic switching of a mobile device or laptop when moving it.

For us, the fact that when we move from one Wi-Fi network to another one or when we get into the Wi-Fi zone from the cellular Internet coverage area and vice versa, our device is automatically reconnected.

And at the same time, the connection with the VPN is broken.

In fact, all traffic remains unprotected for the time the VPN app reconnects to the server.

Note it, if you didn’t think about it.

So, I am convinced that a modern VPN should support Kill Switch in all of its apps. This greatly increases the effectiveness of protection in all conditions.

VPN services with Kill Switch

After testing over 40 VPNs, I’ve pointed out the 5 best services that support automatic blocking. I’ve tested all platforms using a special Wireshark packet sniffer and my software to test the operation on mobile devices.

I placed the selected providers in the table, where I also indicated their main characteristics.

Comparisons of the best VPN services with Kill Switch

Service Ranking
(out of 10)
Kill Switch Number of servers Country selection Price (monthly)
ExpressVPN 10 Classic 3000+ 94 $6.67-12.95
NordVPN 10 Advanced 5000+ 59 $4.13-11.95
Surfshark 10 Full 1700+ 63 $2.49-12.95
CyberGhost 9 Classic, uninterrupted 6500+ 90 $2.25-12.99
PIA 8 Classic 3400+ 45 $2.69-9.95

 Next, I will briefly describe all 5 services and show their test results.

ExpressVPNExpressVPN logo


  • Kill Switch works 100% efficiently
  • Protection activated by default
  • User-friendly reviews
  • One of the fastest VPNs
  • 94 countries support
  • AES-256 encryption
  • Apps installation without any authentication


  • No WireGuard protocol support  


Today, ExpressVPN service is considered one of the strongest and large providers. Its history dates back more than 10 years, and during this time it has always been considered the flagship of the VPN industry.

A high level of service requires frequent confirmation. Therefore, I examine all aspects of ExpressVPN more often than most other providers.  

The results of the 2020 studies confirm the claimed characteristics. Kill Switch (“Stop all internet traffic if the VPN disconnects unexpectedly”) protects 100% of the data, including DNS queries and P2P traffic.

Kill Switch in ExpressVPN

 The provider works equally efficient on all OSs.


Express VPN offers three tariff plans that differ in duration of subscription:

  1 month 6 months 1 year
Monthly cost $12.95 $9.99 $6.67
Money-back guarantee, days 30 30 30

Prices include an extra 20% discount for those who follow the cooltechzone.com link.

ExpressVPN Preview
Repeatedly Confirmed Premium Quality VPN

Also read:

NordVPNNordVPN logo


  • Leader in popularity (according to the Google Trends)
  • Advanced Kill Switch
  • WireGuard
  • 5000+ servers in 59 countries
  • Double VPN
  • Tested on all OSs
  • Obfuscation
  • Static IP


  • There are some servers with low speed


NordVPN is another high-level service that is ideal for universal use with 100% security. In terms of data protection, it is distinguished by two important features:

  1. Advanced Kill Switch
  2. No data leakage even when Kill Switch is turned off

NordVPN can protect even in the most extreme situations. Firstly, it will block all traffic in case of problems with the VPN channel, and secondly, it will immediately terminate pre-selected apps.

Proven safety of NordVPN

As an expert, I’ve chosen NordVPN for myself.


NordVPN offers four tariff plans that differ in duration of subscription and price *:

  1 month 1 year 2 years
Monthly cost $11.95 $4.92 $4.13
Money-back guarantee, days 30 30 30

* Price includes current discounts.

NordVPN Preview
Use the multifunctional VPN service with a maximum level of protection

Also read:

SurfsharkSurfshark VPN logo


  • Cheap service with excellent features
  • Full Kill Switch (blocks even with manual shutdown)
  • Bypass VPN locks
  • Double VPN (MultiHop)
  • Unlimited number of devices
  • Static IP


  • Doesn't use diskless servers
  • There are locations with low speed


If you look at the prices and doubt about the choice of service, aren’t sure what is written about them is true, then I suggest you try Surfshark.

This VPN provider is practically not inferior to ExpressVPN or NordVPN, but it costs significantly less (with prolonged use).  

Surfshark test showed excellent protection results on all OSs except Linux. At the same time, the service offers additional features that are unparalleled with other VPNs. This is BlindSearch, which makes Internet searches as private as possible, and HackLock is innovative email protection.

Surfshark has the toughest Kill Switch


Surfshark has three tariff plans:

  1 month 6 months 2 years
Monthly cost $12.95 $6.49 $2.49
Money-back guarantee, days 30 30 30

BlindSearch and HackLock are available for extra $ 0.99 per month.

Surfshark Preview
Use affordable high-quality VPN for any task

Also read:

CyberGhostCyberGhost VPN logo


  • Uninterrupted Kill Switch
  • The largest server database
  • Special server lists for popular topics
  • Split Tunneling


  • Connects to Windows slower than other apps
  • High power consumption on Windows


If Kill Switch is so needed, then why is it just one of the features for most VPNs? CyberGhost developers, it seems, have weighed all the pros and cons and made it impossible to disable this option in the app settings:

CyberGhost doesn't allow to disable the Kill Switch option

Regarding general specifications, CyberGhost provides premium quality services. It is convenient for streaming, torrenting, and especially delicate tasks (when using secure NoSpy servers).

Criticism is caused only by the Windows app.

When it was tested on two different computers, the software noticeably slowed down and connected for a bit longer than other VPNs of a similar level.


CyberGhost VPN has four tariff plans. Really cheap is only a 3-year subscription:

  1 month 1 year 3 years
Monthly cost $12.99 $3.99 $2.25
Money-back guarantee, days - 45 45

The service allows you to order your own dedicated IPs ($5 per month for each IP address).

Also read:

Private Internet AccessPIA VPN logo


  • Two Kill Switch modes
  • High speed
  • Enhanced privacy
  • WireGuard


  • Not suitable for Netflix, Hulu and Disney +


Private Internet Access (PIA) is widely known as a service with a principled position on the protection of user privacy and, at the same time, has developed technical functionality. All OS apps allow you to configure basic and rarely seen VPN connection parameters.

Killswitch (at PIA it is called that way) can be used in two modes:

Private Internet Access Has Double Kill Switch

Auto (classic) and Always (full, blocking traffic when VPN is off).

I note that since the end of 2019, PIA has been owned by Kape Technologies which also owns CyberGhost.


Private Internet Access is a cheap VPN service

  1 month 1 year 2 years
Monthly cost $9.95 $3.33 $2.69
Money-back guarantee, days 30 30 30

PIA is also one of the few VPNs that accept anonymous Zcash cryptocurrency.

Also read:


How does the Kill Switch work?

The principle of protection against leakage of insecure data is similar to the operation of a firewall. A special driver ensures that the connection to the VPN server is active. At the same time, traffic routing occurs in such a way that only the VPN port remains open for remote connections. In case of communication failure, this port is blocked.

What VPN services don’t support Kill Switch?

Most VPNs in force in 2022 don’t support this feature in whole or in part. Partially, it means the absence of an option in apps for some platforms.

For example, the following popular services don’t support Killswitch fully:

  • Betternet
  • DotVPN
  • Hola VPN
  • Opera VPN
  • Turbo VPN
  • VPNBook
  • Hoxx VPN
  • Touch VPN

Is there an alternative to Kill Switch?

Yes, there is. Additionally, you are to install a firewall and configure it so that it blocks all packets that go not to the local IP address of the virtual network. From my own experience, I know that such settings aren’t flexible and, if you use a VPN service, then most often you will have to reconfigure the firewall with every connection.

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