How to Connect a Modem to a Router, Step by Step

On this page (8 sections)

1. How do you connect a modem to a router step by step?
2. Which cables go where when connecting a modem to a router?
3. Does the modem need activation before you connect the router?
4. How do you set up Wi-Fi after connecting the router?
5. What should you choose when buying cables for this setup?
6. What mistakes can stop a modem and router from connecting?
7. Can you connect a router to a modem-router combo?
8. What is the best way to connect a modem to a router?

To connect a modem to a router, run coax from the cable outlet to the modem, then Ethernet from the modem to the router’s WAN port. Activate the modem with your provider, then power on the modem before the router.

This is the basic order for learning how to connect a modem to a router and bring Wi-Fi to your devices.

A standalone cable modem brings internet service into your home. The router shares that connection with phones, computers, TVs, and other devices.

How do you connect a modem to a router step by step?

Connect coax, then Ethernet, and power the modem before the router. Activate the modem with your provider if required, and wait for it to connect before setting up Wi-Fi.

1. Turn off and unplug the modem and router.
2. Connect a coax cable from the wall outlet to the modem’s coax port. Tighten the connector by hand.
3. Plug one end of an Ethernet cable into the modem’s Ethernet port.
4. Plug the other end into the router’s WAN or Internet port.
5. Connect the modem’s power cord and turn it on.
6. Wait for the modem to start and connect to your provider’s network.
7. Turn on the router and wait for it to connect.
8. Use the router’s app or instructions to set up Wi-Fi.

The modem and router may take several minutes to start. Keep them connected while their lights change, and use the device instructions to tell when startup is complete.

Which cables go where when connecting a modem to a router?

Coax connects the cable outlet to the modem; Ethernet connects the modem to the router. The router’s WAN or Internet port takes the modem connection, while its LAN ports are for wired devices.

The modem’s coax port is a round threaded connector. Its Ethernet port looks like a wider phone jack.

Router ports may be labeled, and the WAN or Internet port may have a different color from the LAN ports.

For a modem close to the outlet, choose an RG6 coax cable with F-type connectors. The Nixsto RG6 cable is a 6 ft option, and other lengths are available.

The GE RG6 Coaxial Cable is another 6 ft choice, with quad shielding and a flame-retardant jacket for in-wall use.

Measure the route before picking a length. Keep coax away from tight bends, pinches, and walkways where someone could trip over it.

For the modem-to-router link, use an Ethernet cable with RJ45 connectors. The Amazon Basics Cat 6 cable is 10 ft long, which suits a setup where the router sits a short distance from the modem.

See our guide to choosing an Ethernet cable for a modem for help with cable categories and lengths. If your router needs to sit far from the outlet, plan the Ethernet route before placing the modem.

Does the modem need activation before you connect the router?

Usually, activate the modem with your internet provider before setting up the router. Providers may offer activation online, in an app, or by phone.

Follow your provider’s instructions to register the modem and connect it to your account. You may need the modem’s serial number or MAC address, often printed on its label.

Wait for the modem to connect before moving on. If it hasn’t been activated, the router may show no internet even when both cables are in the correct ports.

How do you set up Wi-Fi after connecting the router?

Use the router’s app or setup page to create a Wi-Fi name and password. Keep the router connected to the modem and follow the router’s setup instructions.

If the router was used before, it may still have an old Wi-Fi name and password. Follow the maker’s reset instructions if you need to start over, since a reset can erase saved settings.

Connect one phone or computer to the new Wi-Fi network and open a few websites. Once that works, connect your other devices.

A wired device can help narrow down a problem. Connect a computer to one of the router’s LAN ports with Ethernet and check whether it can reach the internet.

What should you choose when buying cables for this setup?

Choose cable types and lengths to match the route from outlet to modem and modem to router. A short coax cable is suitable when the modem sits near the outlet, while a longer Ethernet cable can give you more choice in router placement.

Measure the path before you buy. Leave enough length for gentle bends and device movement, but avoid loose cable that can snag or become a trip hazard.

Choose the Nixsto RG6 cable if you need a basic length option for an indoor or outdoor coax connection. Choose the GE RG6 if the quad shielding or flame-retardant jacket for an in-wall route suits your setup.

The Amazon Basics Cat 6 cable fits a modem and router placed within its 10 ft reach. Skip it if your planned route is longer or needs an outdoor cable.

The VCE Coaxial Surge Protector is an inline accessory with a metal housing and sealed F-ports. It suits a coax connection where you want surge protection, but skip it if you need a direct coax connection or your provider or equipment instructions don’t allow the accessory.

What mistakes can stop a modem and router from connecting?

The most common setup mistakes are using the wrong router port, skipping activation, or powering devices on in the wrong order. Check those basics before changing router settings.

• Confirm that coax is secured at the wall and modem.
• Connect Ethernet from the modem to the router’s WAN or Internet port, not a LAN port.
• Activate the modem with your provider.
• Restart the modem, wait for it to connect, then restart the router.
• Try another Ethernet cable if you have one available.

Avoid adding a splitter or extra adapter unless your provider’s instructions or your setup call for one. Each extra connection can make a signal problem harder to locate.

Look at the modem’s lights after startup. Their meanings vary by model, so use the labels and instructions for your device.

Our guide to modem lights that are blinking explains common patterns.

If the modem still has no internet, follow the steps in modem not connecting to the internet before changing router settings.

Can you connect a router to a modem-router combo?

Yes, but a modem-router combo already combines both functions, so a second router may be unnecessary. Add one if you need different Wi-Fi features or more coverage, and check the combo’s instructions before changing settings.

A separate router connected to a combo can create two local networks. Some combos offer bridge mode so a separate router can handle the network, but follow the combo maker’s and provider’s instructions before enabling it.

If you’re choosing between separate devices and one combined unit, see what a modem-router combo is. Check your provider’s requirements before buying equipment.

What is the best way to connect a modem to a router?

Connect coax to the modem, Ethernet to the router’s WAN port, and power the modem first. Choose cable lengths for your layout, activate the modem, and then set up the router’s Wi-Fi.

Pick the Nixsto RG6 for a straightforward coax replacement, the GE RG6 for an in-wall route, or the 10 ft Amazon Basics Cat 6 for a nearby modem and router. Add the VCE surge protector only if an inline coax accessory fits your provider’s instructions and setup.

For help with the wired connection, read our guide to Ethernet cables for modems. If you still have no internet, use the modem connection troubleshooting steps.

Frequently asked questions

Which port connects the modem to the router?

Connect an Ethernet cable from the modem’s Ethernet port to the router’s WAN or Internet port. The modem’s coax port connects to the cable outlet, while the router’s LAN ports connect to wired devices such as computers and TVs.

Should I turn on the modem or router first?

Turn on the modem first and wait for it to finish starting, then turn on the router. This gives the router time to get an internet connection from the modem.

If your provider requires activation, complete that step before troubleshooting the router.

Can I connect a router without a modem?

A router needs an internet source, such as a modem, to provide internet access over Wi-Fi. You can connect devices to the router’s local network without a modem, but they won’t reach the internet unless the router has another active connection.

Can I use any router with my cable modem?

Most standalone routers connect to a cable modem with Ethernet, but check your provider’s setup instructions and the router’s WAN port. If you have a modem-router combo, you may need to adjust its settings or use a separate router mode to avoid setup conflicts.