If you’ve ever logged into your router’s settings, you’ve probably come across an option called VPN Passthrough. Does it create a VPN connection? Does it improve your online privacy? Or is it something you need to enable before using a VPN?
In this guide, we’ll explain what VPN passthrough is, how it works, the different types of VPN passthrough, and whether you should enable or disable it on your router.
What is VPN Passthrough?
VPN passthrough is a router feature that allows VPN traffic to pass through your router’s firewall without being blocked. Its main job is to recognize VPN connections and let them travel normally between your device and the VPN server.
This feature was originally designed to help older VPN protocols, such as PPTP, L2TP, and IPsec, work properly with routers that use NAT (Network Address Translation). These protocols don’t always interact well with NAT, so a router may mistakenly block or interrupt the connection. VPN passthrough solves this by allowing the VPN traffic to pass through correctly.
How Does a VPN Passthrough Work?
When you connect to a VPN, your device sends encrypted traffic through your router before it reaches the VPN server. Normally, the router checks and manages all incoming and outgoing traffic to keep your network running smoothly.
However, some older VPN protocols don’t communicate with routers as cleanly as modern ones do. Since many home routers use NAT (Network Address Translation) to manage multiple devices on the same network, they may have trouble correctly recognizing or forwarding certain VPN packets. As a result, the VPN connection can fail or become unstable.
VPN passthrough solves this problem by recognizing supported VPN traffic and allowing it to pass through the router without unnecessary interference. Instead of treating the VPN packets as unfamiliar traffic, the router forwards them to the correct device, making it possible to establish and maintain the VPN connection.
Types of VPN Passthrough
Most routers support three common types of VPN passthrough, each designed for a different VPN protocol.
PPTP Passthrough
PPTP passthrough allows VPN connections that use the PPTP (Point-to-Point Tunneling Protocol). PPTP is one of the oldest VPN protocols and is known for its fast speeds. However, it has significant security weaknesses and is no longer recommended for protecting sensitive data. Today, it is mainly found in older devices and legacy business networks.
L2TP Passthrough
L2TP passthrough supports VPN connections that use the Layer 2 Tunneling Protocol (L2TP), usually combined with IPsec for encryption. Compared with PPTP, it offers stronger security but may be slower because of the additional encryption. Some organizations still use L2TP/IPsec, although it has become less common in recent years.
Read more: L2TP VPN Guide: How It Works, Pros, Cons & Comparison
IPsec Passthrough
IPsec passthrough enables routers to handle VPN traffic protected by the IPsec protocol. IPsec is widely used in business VPNs because it provides strong encryption and secure communication between networks or remote users. If you connect to a corporate VPN, IPsec passthrough is often the feature that keeps the connection working properly.
VPN Passthrough vs. VPN Router
Although their names sound similar, VPN passthrough and a VPN router serve completely different purposes.
A VPN passthrough is simply a router feature that allows certain VPN traffic to pass through the router without being blocked. It doesn’t create a VPN connection or encrypt your internet traffic. Instead, it helps compatible VPN connections work properly, especially those using older protocols.
A VPN router, on the other hand, actively runs a VPN connection on the router itself. Once configured, every compatible device connected to the router automatically uses the VPN, even if the device doesn’t have a VPN app installed.
| Feature | VPN Passthrough | VPN Router |
|---|---|---|
| Purpose | Allows VPN traffic to pass through the router | Creates and manages a VPN connection |
| Encryption | Does not encrypt traffic | Encrypts internet traffic for connected devices |
| VPN software required | Yes, on the device | Usually only on the router |
| Best for | Older VPN protocols and business VPNs | Protecting all devices on a network |
Read more: How to Setup VPN on Router? Easy Guide!
How to Enable VPN Passthrough?
Most modern routers have VPN passthrough enabled by default, so you usually don’t need to change this setting. The exact steps vary depending on your router brand:
- Open a web browser and log in to your router’s admin page.
- Enter your administrator username and password.
- Go to the Advanced, Security, or VPN settings menu.
- Find the VPN Passthrough option. Some routers may list separate settings for PPTP, L2TP, and IPsec passthrough.
- Enable or disable the feature as needed, then save your changes.
- Restart your router if prompted, and test your VPN connection again.
Should You Enable or Disable VPN Passthrough?
For most users, it’s best to leave VPN passthrough enabled. It doesn’t create a VPN connection or affect your internet speed, and it only allows supported VPN traffic to pass through when needed.
You may consider enabling it if:
- You use an older VPN protocol such as PPTP, L2TP, or IPsec.
- You connect to a company or school VPN that relies on these protocols.
- Your VPN connection fails to establish through your router.
You can usually leave it disabled if:
- You never use a VPN.
- Your router manufacturer specifically recommends turning it off.
- You’re troubleshooting a network issue and have confirmed that VPN passthrough is the cause.
In most home networks, you won’t need to change this setting manually because modern VPN protocols like WireGuard and OpenVPN work without relying on VPN passthrough.
FAQ about VPN Passthrough
1. Is VPN passthrough the same as a VPN?
No. VPN passthrough is a router feature that allows certain VPN traffic to pass through the router. It does not create a VPN connection or encrypt your internet traffic.
2. Does VPN passthrough improve security?
No. VPN passthrough doesn’t provide encryption or additional protection. It simply helps compatible VPN traffic pass through your router correctly.
3. Does VPN passthrough slow down my internet?
No. VPN passthrough itself doesn’t reduce your internet speed. If your VPN feels slow, the cause is more likely to be the VPN server, protocol, or your network connection.
