VPN kill switch hero desktop

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What is a VPN kill switch, and how does it keep your data secure?

Verified by Nick Jones Editor-in-Chief

A kill switch is immediately triggered once your internet connection is interrupted, making it a vital feature of your VPN’s protection. In this article, we’ll explore this feature and how it works

A VPN kill switch is a critical feature that protects your online data and privacy from accidental exposure. While online, your personal information can become traceable to advertisers and businesses, and these can use your location and IP address to develop a profile based on your details. Without a VPN kill switch, you increase the risk of data exposure and potentially allow unauthorised access to your network, making it easier for cybercriminals to steal your personal information.

A kill switch immediately cuts off internet access if your VPN connection drops, preventing any accidental exposure and safeguarding your data from being transmitted outside of the encrypted tunnel. 

In this article, we’ll discuss everything you need to know about a VPN kill switch, including how it works, types of kill switches, the best version and how to activate one properly.

What is a VPN kill switch?

A VPN service helps to protect your privacy by cloaking your personal data and anonymising your connection. It conceals your real location, identity and IP address. A VPN kill switch is an advanced feature that’s offered by most VPN service providers in the market. 

You may think that staying anonymous online is only a matter of running your internet through an encrypted VPN tunnel. However, there’s more to it than that. Using a VPN is a great way to keep your online activity anonymous – yet it’s not completely foolproof. Spikes in your network activity can cause your internet connection to drop, leaving your personal information and IP address exposed to prying eyes. 

Without a kill switch, if your internet connection drops, your online activity will not remain encrypted, which potentially exposes your personal information to your internet service provider (ISP), surveillance teams from different organisations, or cyberhackers. In addition, your real IP address and location may be exposed when manually reconnecting to the VPN without a kill switch.

How does a VPN kill switch work?

A VPN kill switch typically works in the following ways: 

  1. Monitoring the VPN connection: a kill switch continuously monitors your VPN connection status
  2. Detecting a connection drop: if the kill switch detects the VPN connection is no longer stable or active, it immediately triggers an action to block internet traffic
  3. Cutting off internet access: once the kill switch is activated, regular internet connection cuts off, preventing data leakage
  4. Restoring the VPN connection: when the VPN connection is stabilised or restored, the kill switch resumes internet access, ensuring all internet traffic is routed through the VPN

Benefits of using a kill switch

There are several benefits to using a kill switch:

  • Data protection: a kill switch prevents unencrypted data from being transmitted online, shielding your sensitive information from potential interception
  • Privacy enhancement: a kill switch helps you to maintain anonymity by preventing accidental exposure of your real IP address and location
  • Reinforcement: you can have peace of mind using a kill switch; it acts as a fail-safe measure that enhances your VPN’s security
  • Torrenting and peer-to-peer (P2P) safety: a kill switch is essential for users engaged in file-sharing activities. It prevents accidental exposure of your real IP address while downloading or uploading torrents, diminishing the probability of privacy breaches

When does a VPN kill switch activate?

A VPN kill switch can be activated in these circumstances: 

  • A drop in your VPN connection: if your internet connection drops or becomes unstable, the kill switch is automatically activated to block internet traffic to and from your device
  • VPN connection failure: when the VPN fails to establish a secure connection or encounters an error, the kill switch is triggered
  • Network switching: upon switching from one network to another, such as switching from wifi to mobile data, there may be a brief moment when the VPN connection is interrupted. The kill switch is activated during this transition
  • Startup and shutdown: to ensure the kill switch is always effective, some VPN clients can activate it during the startup process and deactivate it during the system’s shutdown

Types of VPN kill switches

There are two main types of kill switches: 

  • An application-level kill switch
  • A system-level kill switch

Both types of kill switches serve the same purpose of preventing data leaks. Some VPN services offer both types of kill switches, allowing users to choose their preferred one based on their needs. 

System-level kill switch 

A system-level kill switch functions at the operating system level outside of the VPN client application. It monitors and controls internet traffic at the lower level of the network stack. If the VPN connection fails, this type of kill switch blocks all internet traffic.

A system-level kill switch typically offers broader protection, as it covers all network connections. 

Application-level kill switch 

An application-level kill switch operates at the application level within the VPN client software. It provides advanced control by allowing you to select which apps should stop connecting to the internet when the kill switch activates, giving you more flexibility in managing your online activities.

How to activate and configure a VPN kill switch

VPN services offer different kill switch activation and configuration processes. Here are some general steps to activate and configure a VPN kill switch:

  1. Launch: open the VPN client software on your device
  2. Locate: locate the kill switch option within the VPN software settings. The name of the kill switch may vary. For example, NordVPN simply calls it a kill switch, ExpressVPN’s Windows app has “Network Lock” settings, and CyberGhost has an automatic kill switch option 
  3. Enable: most VPN service providers offer a simple on/off toggle to enable the kill switch
  4. Configure: some VPN service providers allow users to customise the behaviour of the kill switch, so you may have the option of choosing between an application-level or a system-level kill switch. You can specify which applications or processes should be blocked when the VPN connection drops
  5. Save and apply: once you’ve configured the kill switch settings, save and apply the settings so your kill switch is ready to be used

What’s the best VPN kill switch?

Many VPN providers offer a kill switch feature, but not all of them are reliable. When choosing a VPN service provider, consider your personal preferences and keep in mind factors such as reputation, reviews, audited no-log policies and user ratings.

Is there a free VPN with a kill switch?

There are only a handful of trusted free VPN providers that offer a kill switch feature, as it’s typically a sought-after option. However, we’ve found the following free VPN providers that feature a kill switch: 

Round up of today’s best VPN deals
NordVPN 2 year £2.49 /Month
£2.49 /Month
Surfshark 24 month £1.79 /Month
£1.79 /Month
ExpressVPN 12 month £6.77 /Month
£6.77 /Month
CyberGhost 2 year £1.78 /Month
£1.78 /Month
Proton 2 year £4.27 /Month
£4.27 /Month
PIA 2 year £1.57 /Month
£1.57 /Month
Atlas 2 year £1.34 /Month
£1.34 /Month
PrivadoVPN 2 year £1.99 /Month
£1.99 /Month
Windscribe 12 month £4.53 /Month
£4.53 /Month
IPVanish 2 year £3.58 /Month
£3.58 /Month