NAT vs Bridge Mode: When to Use Each on Your Router

What NAT and bridge mode mean

NAT, short for Network Address Translation, is the function a router uses to translate the private addresses of your devices into the public address of your internet connection. Bridge mode is a setting that stops a router from doing that translation and routing, so the device passes traffic between its internet port and its LAN ports and Wi-Fi without managing addresses itself.

These words appear in a router's manual and settings more often than in a listing title. When a listing says a router can run in access point mode, or a mesh kit includes units that are not the main router, bridge mode is the idea behind those modes: the device is not the one managing the connection. If you are deciding whether to use a separate router or a device that combines the internet connection and router functions, the modem router combo vs separate article is a related question.

How NAT works in a home network

In a typical home, the internet arrives through a single connection. The router gives each device a private address, translates that address to the public address of the internet connection when traffic goes out, and tracks the connection so replies return to the right device. That translation is NAT.

NAT is the default behavior for most home routers. It is what lets a network with several devices share one internet connection without each device needing its own public address. On a listing, the words router or gateway mode mean the device is expected to do this work.

What bridge mode does

In bridge mode, the router does not assign addresses, does not translate, and does not route between networks. It connects the network on its internet port to the network on its LAN ports and wireless network, acting more like a switch or an access point.

The reason to use bridge mode is that another device upstream is already doing the routing. That device, often the gateway your internet provider supplies or another router you already own, handles NAT and address assignment. The device in bridge mode simply extends the network to more rooms or more wired ports. The difference between a bridge-like device and an access point is covered in the mesh vs access point article.

When to keep NAT on

Keep NAT on when this router is the only router between your home network and the internet. That is the usual setup for a household: the router connects to the internet entry point and routes for the whole home.

Most single-router listings on this site describe routers that work in this mode. If you are buying a router for a move, a new apartment, or a first router of your own, the usual choice is a router that keeps NAT on and acts as the main router. The Best Router guide compares these routers on their stated details.

When to use bridge mode

Use bridge mode when you already have a router doing the routing and you want the new device to extend that network. Common situations: the gateway from your internet provider must stay in place; you have a mesh system where the main unit routes and satellites connect to it; or you are using an older router as a second access point in a home office or a far room.

Bridge mode is what a mesh satellite does by design: only one unit in a mesh system manages the connection, and the others pass traffic to it. The Best Mesh Wi-Fi Systems guide explains how these kits are described on listings.

Reading the listing terms

The words NAT and bridge mode rarely appear in a listing title. Titles use phrases that imply them: router means the device does routing and NAT; access point mode or AP mode means the device can be set to bridge-like behavior; and a mesh kit with multiple units is understood to have one unit doing the routing and the others connecting to it.

When a listing is unclear, read the maker's page for the model. The page usually lists the operating modes, such as router mode, access point mode, and sometimes a bridge mode setting. The access point mode article and the NAT ports article cover related parts of this question.

• Questions to ask the maker:
• Does this model have an access point mode?
• Which unit in a mesh kit is the main router?
• Does the kit allow wired backhaul between units?

Following the maker's manual

Choosing between NAT and bridge mode is a settings decision, not a shopping decision. The router's manual and its setup app describe where the mode switch lives and what each mode needs from the network around it. For example, a device in bridge mode usually expects the upstream router to assign addresses, and the manual tells you how to connect the two devices.

For guidance on router settings related to security, follow the maker's manual and read the NIST and Wi-Fi Alliance security pages in the sources. This site compares routers on stated details; it cannot advise on your specific network's security choices.

What to pick for your situation

Questions

Is NAT the same as a firewall?

No. NAT translates addresses between your home network and the internet; a firewall is a separate function that filters traffic. On many home routers both are on by default, but they are different features. For firewall settings, follow the maker's manual.

Does bridge mode turn off Wi-Fi?

No. Bridge mode keeps the wireless network working; it changes how the device handles traffic between the internet port and the rest of the network. The Wi-Fi name and settings remain, and the manual explains how to set the same network name as the upstream router if you want one network.

Do mesh satellites use NAT?

No. In a mesh kit, one unit is the main router and does the routing and NAT; the satellite units connect to it and do not translate addresses. This is why mesh listings often describe units that are not the main router.

Can I put any router in bridge mode?

Most routers offer an access point mode or a similar setting, but the exact name and location differ by maker and model. Read the maker's page for the model or ask the maker directly.

What if my internet provider gives me a gateway?

The gateway your internet provider supplies often does the routing. If you want your own router to handle Wi-Fi instead, check the provider's own requirements, since setups vary. This site cannot name a provider or promise compatibility.

Does bridge mode affect the Wi-Fi standard?

No. Bridge mode changes routing behavior, not the Wi-Fi bands or generation a router supports. A Wi-Fi 6 or Wi-Fi 7 router in bridge mode still uses the same wireless technology; the Wi-Fi Alliance describes generations on its MAC/PHY page.