What is Mozilla VPN’s emergency stop (Kill Switch)? | Assistance from Mozilla VPN, the VPN Emergency Depart (Kill Switch) protects your IP address | Proton VPN

Protect your connection with our emergency stop functionality (Kill Switch)

Proton VPN was designed by the team, which is the source of Proton Mail, the largest encrypted messaging in the world, and Proton is recommended by the UN as an effective way to circumvent censorship.

What is Mozilla VPN’s emergency stop (Kill Switch) ?

We need your input! Help Us Enhance Your Mozilla Support Experience and Shape the Future of Our Site by Joining Our User Research Study.

An emergency stop of the VPN, called Kill Switch in English, is an essential element for reasons of confidentiality when you use a VPN. If you actively use the VPN to transfer data and your internet connection becomes unstable or falls, the entire network connection of your device will be blocked to prevent your local IP address from being exposed to the outside world. The emergency stop is activated by default under Windows, Android, iOS, Mac and Linux, and there is no parameter allowing it to deactivate it.

Associated articles

To know more

These people helped write this article:

Illustration of Hands


Develop and share your expertise with others. Answer questions and improve our knowledge base.

Protect your connection with our emergency stop functionality (Kill Switch)

Keep control permanently on people who can see your IP address through the Proton emergency (Kill Switch) functionality, which even protects you in the event of unexpected interruption of your internet access.

Protect your IP address permanently

Proton VPN is respectful of privacy. Our emergency stop functionality (Kill Switch) masks the IP address of your device even if your VPN connection is interrupted, which allows you to stay safe whatever happens.

Stay safe on unreliable networks

Wherever you are, our emergency stop functionality (Kill Switch) constantly monitors your connection to our VPN servers. If the connection is accidentally interrupted, all the traffic from your device is immediately blocked, which protects your IP address and your DNS requests.

Emergency stop (Kill Switch) assures you permanent security

Our emergency stop functionality (Kill Switch) does not disturb your connection speed or your navigation and represents a precious final defense line. It guarantees that your navigation remains private if your Internet service provider (ISP) has a short breakdown or if you change wifi network.

Keep control

You can activate emergency stop (Kill Switch) when you access sensitive information or use it permanently to make sure your Internet connection is always protected by Proton VPN.

Secure your connection with Proton VPN

Advanced safety features

Our Secure Core architecture puts your traffic through several servers before leaving our network, which is an additional line of defense against the network -based attacks. Associated with protection against DNS leaks and our non-journalization policy (no logs), it guarantees the confidentiality of your navigation history.

Ultra fast servers

You can get speeds up to 10 gbit/s. Using only ultra fast servers, we are able to provide the strongest without compromise on performance.

Based in Switzerland

Our headquarters are in Switzerland and we are protected by some of the strictest laws in the world in terms of privacy. We are also outside the courts of the United States and the European Union: no one can spy on you.

Reliable and fast VPN for all

Persistent confidentiality

We only use encryption that supports persistent confidentiality (PFS – Perfect Forward Secrecy): even if a encryption key was compromised, all other sessions would remain safe.

Permanent VPN

Our permanent VPN functionality automatically restores a connection to a VPN server if your connection is interrupted.

VPN without newspapers (no log)

Our strict non-journalization policy (no log) means that we can in no way transmit your data to anyone.

Full disk encryption

Even if a person physically accesses a server, the full encryption of the discs ensures that attackers cannot access the encryption keys kept there.

Open source

For total transparency, all of our applications are fully open source so that everyone can examine our code. We have also published independent audit reports on our website.


Proton VPN was designed by the team, which is the source of Proton Mail, the largest encrypted messaging in the world, and Proton is recommended by the UN as an effective way to circumvent censorship.

VPN Accelerator

VPN Accelerator is a set of exclusive technologies to Proton VPN which can increase the speed of your VPN by more than 400 %.

No advertising

We never show you advertisements and never use trackers in applications or on our website. It also helps protect your privacy.

sweep to the right or left to discover all the values

Choose a quick and secure VPN

  • Secure navigation on public WiFi networks
  • Strong encryption
  • DNS leaks protection
  • Ultra fast servers
  • VPN Accelerator

frequently asked Questions

What is the emergency stop functionality (Kill Switch) ?

Proton VPN’s emergency stop functionality blocks all network traffic in the event that connection to the VPN server you have chosen is interrupted. This does not disturb the quality of your connection as long as your VPN remains connected. By blocking all traffic, this functionality prevents your single IP address from being accidentally compromised.

Why use the emergency stop functionality (Kill Switch) ?

When you use a VPN, your navigation activity is encrypted, which allows you to hide your IP address and protect your private data. If you lose your connection with our VPN server, the emergency stop functionality (Kill Switch) intervenes and blocks your Internet connection. This prevents your private data from being exposed to anyone watching your connection (such as hackers or your Internet access provider). Using this feature allows you to keep control over people who access your data.

Why would a VPN connection be interrupted ?

We maintain a reliable network, there are nevertheless several reasons why your VPN connection can be interrupted:

  • Low WiFi signal power
  • Maintenance server
  • Passage from one network to another (for example from WiFi to the mobile network)

Does the emergency stop functionality (Kill Switch) protect me when I start my device ?

We propose the emergency stop functionality (Kill Switch) permanently to prevent any connection outside the VPN interface, including at startup and in the event of loss of the VPN connection under navigation. Your internet connection is also interrupted if you manually disconnect from the VPN.

Can I use the emergency stop functionality (Kill Switch) with a VPN Free Proton subscription ?

Yes, this feature is available with all VPN proton subscriptions.

  • Free VPN
  • VPN servers
  • VPN for streaming
  • VPN for Netflix
  • VPN Secure Core
  • Start well
  • Download the VPN
  • VPN for Windows
  • VPN for Mac
  • VPN for Android
  • VPN for iOS
  • VPN for Linux
  • VPN for Chrome
  • VPN for Firefox