Can You Connect A Router To A Modem Without An Ethernet Cable?

Setting up a home network can be confusing with all the different jargon of routers, modems, ethernet, Wi-Fi etc, and one simple thing some users want to know is if a router and modem can be connected wirelessly (ie. without an ethernet cable). Is it possible to connect a modem and router together without needing to use any network cables?

It would be nice if this was possible, but unfortunately it’s not:

It is not possible to connect a router to a modem without an ethernet cable. A modem must be connected using an RJ-45 ethernet cable to the WAN port on the router, in order to communicate with each other.

Therefore to set up any fixed line internet service in the home, at least some cabling is required to get the router and modem properly connected.

Let’s look at how home networks tend to be set up to see why.

How To Connect A Router To A Modem (Easy Steps)

We’ve already established that it isn’t possible to wirelessly connect your modem to your router, so let’s look at how you typically do connect these two devices on a home internet setup.

Step #1 – Plug an RJ-45 ethernet cable into the WAN/DSL/ADSL/Internet Port on your router (the differently colored single port separate from the LAN ports):


Click here to view a simple, 5m ethernet cable on Amazon, if you need one. You can also get one at most local stores – just ask for an RJ-45/LAN/Ethernet cable

The modem has to be connected only to the separate WAN/Internet port on the router, and not one of the 4 LAN ports, which are for devices instead. If you connect the modem to a LAN port by mistake, nothing will happen and your network won’t function. See here for a breakdown of all the ports on a router.

Step #2 – Connect the other end of this ethernet cable to the single ethernet port on your separate modem:

The modem then also goes out to the phone line via a slightly smaller RJ-11 port/cable.

Step #3 – Connect devices to one of your router’s (normally 4 LAN/ethernet) ports:


And that’s it! You should have a functional home network, as long as you’ve got a live, activated internet service. But the modem and router do need to be connected by ethernet cable for it all to work.

Devices like computers/phones/tablets etc. can communicate wirelessly with the router, but the router and modem cannot connect via wireless; they must connect via cable to the router’s WAN port.

What You Need To Get Online In The Home

Let’s run through a typical home internet setup to demonstrate what’s required to get working internet through a fixed line connection:

  1. An installed, live, activated internet service from an internet provider (eg. Comcast, BT etc).
  2. Either a standalone router AND and standalone modem, connected together by ethernet cable (older setups); OR
  3. A combined router-modem (newer setups) that goes straight into the phone line.
  4. If setting up the internet for the first time, you’ll also often need to some basic initial modem/router configuration to get started. Some ISP’s have “do it yourself” self installation guides on this (see section below); others still send round technicians to set it up for you.

Setting Up Your Router Without An Ethernet Cable

One thing it IS possible to do without an ethernet cable is to actually set up (or change settings on) your router, once it’s connected to a modem by cable (or a combo model).

This is something that CAN technically be done without a network cable on wireless devices like phone or tablets, as long as you have the credentials to access the router’s Wi-Fi network.

Here are the general steps for this:

Step #1 – Connect to the router’s Wi-Fi – Get your phone, tablet or other portable device, and connect it to your router’s wireless network by finding it on the Wi-Fi network list.

You can find the router wireless credentials on a sticker on the back, something like this:

Note down the wireless/Wi-Fi network name/SSID and password/key (top half of the label above). Find the SSID (Wi-Fi name) on the network list on your device (network/wireless settings), and enter the password to connect.

Step #2 – Enter Router Login Credentials – Now you’re connected to the router, you can login to the router’s configuration panel, to either do the initial setup, or change some other settings. Note down your router login IP/username/password (circled at the bottom of the sample router label above).

Then open any browser on your phone/tablet, and type the login IP (eg. into the browser address bar, and then the username/password.

This should put you into your router settings, and from there you can either set the router up, or modify settings. See our full guide on accessing router settings without a LAN cable, for more detailed steps if you get stuck.

Step #3 – Run Through Initial Router Setup Process

Internet providers are increasingly allowing customers to do “DIY” router installations to keep costs down, but this does mean that sometimes you’ll have to run through some initial router setup steps to get the service up and running and ready to let devices connect and get online.

Here are some links we could find for guides on how to do initial self-setup/installation (DIY install) for routers for major ISPs:


Online gamer and general home networking enthusiast. I like to create articles to help people solve common home networking problems.

Recent Posts