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Field manual

How to set up a VPN kill switch

Analyst
Editorial Team
Filed
2026-05-14
Channel
VPN

A VPN only protects you while its tunnel is up. If the connection drops — a flaky network, a server restart, your laptop waking from sleep — your device silently falls back to your real IP, often without you noticing. A kill switch closes that gap by blocking all traffic the moment the tunnel fails.

What a kill switch actually does#

It's a simple rule: no tunnel, no traffic. The instant your VPN app loses its encrypted connection, the kill switch severs your device's internet until the tunnel is back. Nothing leaks in the seconds before the VPN reconnects.

Turn it on#

Nearly every reputable VPN ships one; it's just off by default. In your VPN app, open Settings → Connection (some call it Advanced), find Kill Switch or Network Lock, and enable it. If you're offered a choice between an app-level and a system-level switch, pick system-level — it covers traffic outside the VPN app too.

Test before you trust it

Never assume a kill switch works because you toggled it. Verify it, using the steps below, before you rely on it for anything sensitive.

Confirm it works#

  1. Connect to the VPN and load a site that shows your IP address.
  2. With that tab open, quit the VPN server connection abruptly (disconnect the server, not the app).
  3. Refresh the page. If the kill switch is working, the page fails to load rather than revealing your real IP.

If the page loads and shows your home IP, the switch isn't active — recheck the setting and prefer the system-level option.

Is it worth the friction?#

Signal

  • Your real IP never leaks on a dropped tunnel
  • Zero performance cost while connected
  • Set once and forget it

Noise

  • An occasional dropped connection cuts you off until reconnect
  • System-level switches can briefly interrupt other apps

For anyone using a VPN for privacy rather than convenience, a kill switch is non-negotiable — leave it on.

Q & A

Frequently asked questions

01
Does a kill switch slow down my connection?
No. A kill switch only watches the tunnel's status and blocks traffic if it drops — it adds no overhead while the VPN is connected.
02
Should I leave the kill switch on all the time?
If you use a VPN for privacy rather than convenience, yes. The small friction of an occasional dropped connection is the point — it's protecting you.

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