You cannot connect a standard, separate router to a separate modem without an Ethernet cable, the WAN port on a router is designed to accept a wired signal from the modem, and no wireless handshake exists to replace that physical link between two distinct devices. If you need to connect router to modem without Ethernet cable, your real options are to eliminate the second device entirely, or to bridge the gap using the wiring already inside your walls: a modem/router combo, MoCA adapters over coaxial cable, or Powerline adapters over electrical outlets. Each of these gives you a stable connection without running a new Ethernet cable between rooms, and the right choice depends on what hardware you already own. Once your network is up, you can connect PC to wifi without Ethernet cable to get your computer online wirelessly.
The truth about connecting your router to a modem without Ethernet cable
Before you try any workaround, understand the hardware limitation. A modem converts your ISP’s signal into digital data, and a router distributes that data to your devices. The only standard way for those two boxes to talk is through an Ethernet cable plugged into the router’s WAN or “Internet” port. Wi-Fi is a feature the router broadcasts to your phones and laptops, it is not a backhaul for the modem’s connection. So if you have two separate devices sitting in different rooms, you cannot simply “pair” them wirelessly. Instead, you have three practical paths: replace both with a single combo unit, reuse your home’s coaxial TV cables with MoCA adapters, or reuse your electrical wiring with Powerline adapters. All three avoid a new Ethernet cable run, but they work in fundamentally different ways.
Option 1: Use a modem/router combo (gateway) instead of two devices
The simplest solution is to stop using two devices altogether. Many Internet Service Providers supply a single gateway, a box that combines the modem and router functions. If you have one of these, the router-to-modem connection simply doesn’t exist as a separate step; the modem side receives the ISP signal and the router side broadcasts Wi-Fi from the same chassis. Check the device your ISP gave you: if it has visible antennas or broadcasts a Wi-Fi network name, it is likely a gateway. You can also log into its settings page (the address is usually printed on a sticker on the unit) and look for both WAN status and wireless settings, if both are present, you already have a combo. With a gateway, you plug the coaxial or fiber line from the wall directly into the device, power it on, and your wireless network is ready. No Ethernet cable is needed between a modem and router because there is no separate router. If your ISP only gave you a plain modem, ask about upgrading to a gateway; most providers offer one for a small monthly rental fee, and it instantly solves the “two boxes in different rooms” problem.
Option 2: Wire your connection using MoCA adapters and coaxial cables
If you have coaxial TV outlets in both rooms, the same round screw-in connectors used for cable television, MoCA adapters can turn those coax lines into a high-speed network backbone. This is the closest thing to a true wired connection without pulling new Ethernet cable. Here is how to set it up:
- Connect one MoCA adapter to your router using a short Ethernet cable, plugging into any LAN port on the router.
- Plug that same MoCA adapter into a nearby coaxial wall outlet using a coax cable.
- Go to the room where your modem is located and plug a second MoCA adapter into a coaxial wall outlet there.
- Connect the second MoCA adapter to your modem’s Ethernet port using another short Ethernet cable.
The two adapters now communicate over the coaxial lines in your walls, bridging your modem and router as if they were connected by a long Ethernet cable. MoCA is reliable and low-latency, making it ideal for streaming or gaming. One caveat: both coax outlets must be part of the same splitter network in your home, if they were wired for separate rooms off the same main line, they will work; if one outlet was disconnected, you may need to reattach it at the junction box. After the adapters are linked, your router will receive internet from the modem through the coax path, and you can configure Wi-Fi normally.
Option 3: Extend your network through electrical outlets with Powerline adapters
Powerline adapters use your home’s electrical wiring as a data highway, which is useful when you have power outlets near both the modem and the router but no coax jacks. They are slightly less stable than MoCA if your wiring is old or noisy, but they require no new cabling whatsoever. Follow these steps:
- Plug one Powerline adapter into a wall outlet near your router and connect it to the router with a short Ethernet cable.
- Plug the second Powerline adapter into a wall outlet near your modem, or in any room where you need a wired connection point, and connect it to the modem with another Ethernet cable.
- Press the pairing button on both adapters (if they have one) to encrypt the link between them.
Once paired, the adapters send data through the electrical circuits in your house, effectively replacing the missing Ethernet cable between the modem and router. The router will see the modem’s connection through the Powerline path, and you can proceed with normal setup. If you only need internet in one additional room, you can also use a single Powerline adapter near the router and a second one near a device like a TV or desktop computer, but for the specific goal of connecting a separate router to a separate modem, place one adapter at each end of that link.
Configure your router's Wi-Fi and test your connection
Once you have established a bridge through a gateway, MoCA, or Powerline, you still need to configure the router’s wireless network if it is a separate unit. Access the router’s settings by typing its IP address into a web browser, this address is printed on the router’s label. Navigate to the wireless settings section and set a network name (SSID) and a strong password. Save the changes and let the router reboot. Then test the connection: on your phone or laptop, find the SSID you just created, enter the password, and open a website. If the page loads, your setup works. If it does not, check that the MoCA or Powerline adapters show a solid link light, and try power cycling the modem and router by unplugging them for a few seconds. If you still have trouble, you can always temporarily connect a laptop directly to the modem with an Ethernet cable to confirm the modem itself is online, and if you forgot the Wi-Fi password you just set, you can find out wifi password through Ethernet cable from a connected PC, but for the final wireless setup, the bridge you built is doing the job. The goal is a working network, and with a gateway, MoCA, or Powerline, you have achieved it without ever needing to unplug Ethernet cable from your old setup and rerun it across the house.
