What Is a VPN Kill Switch? (2026 Guide)
A VPN kill switch blocks your internet if the VPN drops, so your real IP is never exposed. Learn how it works, the types, and which VPNs include one.
What Is a Kill Switch?
A VPN kill switch is a safety feature that automatically blocks your internet connection if the VPN unexpectedly drops. Without it, there is a brief window - when the VPN disconnects and before it reconnects - where your device would fall back to your normal connection, exposing your real IP address and unencrypted traffic. The kill switch closes that gap by cutting off all traffic until the secure tunnel is restored.
How a Kill Switch Works
The VPN app continuously monitors the connection to the VPN server. If that connection drops for any reason - a network change, a server issue, or a signal loss - the kill switch immediately blocks your device from sending or receiving data over the regular connection. Once the VPN reconnects, normal traffic resumes automatically. The result: your data never travels outside the encrypted tunnel.
Types of Kill Switch
- System-wide kill switch: Blocks all internet traffic on the device if the VPN drops. The safest option for privacy.
- App-level (per-app) kill switch: Blocks only specific chosen apps, allowing the rest of your connection to continue. More flexible, slightly less strict.
- Always-on / persistent: Some apps can prevent any internet access unless the VPN is connected, even at startup.
Should You Use One?
For most people, yes - leave the kill switch on. It ensures your identity is never accidentally exposed during a dropped connection, which is exactly when you are most vulnerable. The only trade-off is a momentary loss of internet while the VPN reconnects, which is a small price for the protection. It is especially important on public Wi-Fi, for torrenting, and for anyone who relies on the VPN for privacy rather than just streaming.
Which VPNs Have a Kill Switch
Every VPN in our top ratings includes a kill switch on its main apps, including NordVPN, ExpressVPN, Surfshark, and ProtonVPN. Implementations differ by platform, so our kill switch comparison breaks down exactly how each provider handles it and where the feature is available.