How To Change Comcast Xfinity Modem With Your Own [Guide]

Replace Xfinity Modem

If you are looking to replace your Xfinity modem but are not sure about the process, there is no need to worry as this article will guide you through the steps.

Changing the Comcast Xfinity modem with your own is often recommended as it ensures you can save around $180 per year on rental fees while enjoying better performance, coverage, security features, greater customization, and speed.

You first need to find a compatible modem and router, or modem/router combo, install it and then register it with Xfinity.

Once installed, you can run a test to check the quality of your connection to ensure you are maximizing the benefits of your Comcast Xfinity plan.

In this article, we provide a step-by-step guide on how to replace an Xfinity modem with your own and provide you guidance on features to consider when choosing your device.

How Do I Replace An Xfinity Modem With My Own?

Change Xfinity Modem With Your Own

Below are the steps to follow when changing the Xfinity modem with your own.

1. Buy An Xfinity-Compatible Modem or Modem/Router Combo

The first step is purchasing either an individual modem or a modem/router combo that is compatible with Xfinity. Individual devices normally have a higher initial cost but enable greater customization and are easier to update.

On the other hand, combo devices are easier to set up and save space in your home.

It is important that you verify it is compatible with Comcast Xfinity and ensure it can sustain the speed that you are subscribed to.

If you are using a standalone cable modem, you will need to incorporate a WiFi router to facilitate wireless connectivity.

2. Connect the Cables Correctly

With your external device and accessories in place, you can begin to sort the cables. Follow the steps below:

  • First, disconnect Ethernet cables from your current Xfinity gateway.
  • Place your new modem near the coaxial port and in a location that is accessible to power.
  • Plug in the coaxial cable to the wall socket.
  • Connect the opposite end of the cable to the new modem.
  • Check for any loose cables and reconnect.
  • Plug in the power cord to the power supply.
  • Connect the other end of the power cord to the new modem or modem-router combo.
  • If you are using a separate router, connect the modem to the router using an Ethernet cable.

3. Register & Activate the New Modem

Once the connections have been completed, activate the modem on the Xfinity network via the App or portal. Follow the steps below:

  • Access the portal or app with Xfinity credentials.
  • Begin the activation process.
  • The interface will prompt you to check the connections but as this is already done you can proceed via the “next” button.
  • Locate the active cable outlet.
  • Power on and select “ready to go”.
  • Insert the power cord.
  • Retrieve the CMAC number on your device from the box label or the back of the device. Input and proceed by clicking ‘Next’.
  • Enter the CMAC number.
  • Next click ‘check connection’ to initiate the activation process.
  • Xfinity will need to validate the credentials. This step may take several minutes.
  • Upon verifying details and registering the modem, the service activation will begin. Wait while this process takes place.
  • Keep the device connected as this activation process will take about 10 to 15 minutes.
  • When the process is complete, you’ll get a notification to confirm you’re ready to start.

What Should I Do Next?

Once you have successfully configured your new Xfinity modem, it becomes available for use if it is a modem/router combo device.

In the case of separate devices, you can create a connection through an Ethernet cable.

You should test the connectivity between your modem and router to ensure you have maximum performance.

1. Test Connection

To test the quality of the connection, access the status of the internet connection using the Xfinity app and confirm the subscribed speed. Follow the steps below to do this:

  • Launch the mobile app or web portal.
  • After logging in, view registered devices under your ID.
  • In the ‘check your speed’ section, start the speed test.
  • Perform the speed test.
  • Results show the available download and upload speeds for your connection.

2. Return Xfinity Equipment

As per the terms and conditions, you should return rented devices within 30 days. Failure to return results in a $15 monthly rental charge, even if unused.

To return an Xfinity modem/gateway follow these steps:

Option 1

  • Begin the return process via Xfinity login.
  • Enter the specifics of the device.
  • Select your reason for returning.
  • Print the prepaid UPS label if selected.
  • Pack, attach label, and contact 800- UPS pickup for collection.

Option 2

  • Visit the UPS store near you.
  • Specify it is an Xfinity return.
  • UPS staff will pack the device and return the equipment for free.
  • Retain the receipt for tracking the return process.

Option 3

For visiting a nearby Xfinity/Comcast store, you should schedule an appointment or visit to return equipment. Retain the receipt as confirmation of equipment return.

Is Replacing The Modem Necessary?

Substituting your Xfinity gateway with a personal modem and router eliminates the $15 monthly fee.

If the upfront cost is manageable, the choice is simple, purchasing your own Comcast modem is recommended.

The added expense of obtaining a dedicated Comcast modem is avoidable. Over a span of one year, this fee accumulates to $168, and over two years, it reaches $336.

In contrast, the cost of buying a compatible modem is notably lower than this cumulative cost.

Replacing your modem presents an opportunity to save money. Fortunately, a wide variety of compatible and economically priced modems are readily accessible, allowing you to make a cost-effective choice.

You should also be aware that Xfinity sometimes uses leased modems which can be used as WiFi hotspots for other users.

Although opting out is available, the act of sharing your modem as a hotspot can potentially change the overall performance of your network.

The benefit of owning your router and modem enables you to have greater control. It gives you the authority of securing your network by creating a distinctive name and password.

Features To Consider When Purchasing An Xfinity Compatible Modem

The process of choosing a suitable modem and router for Xfinity is important as you need to consider various factors to ensure it delivers high-quality performance.

Opting for a modem that is not suitable could potentially lead to challenges with activation or post-activation issues with supporting your internet speed.

The good news is that there is a wide range of cable modems that are compatible with Xfinity, which gives you the freedom to select the most suitable option for your network requirements.

An example of factors to consider include the type of DOCSIS technology.

For example, if you have a high-speed internet plan you may consider a modem with DOCSIS 3.1 technology, as this technology can handle ultra-fast internet speeds but at a premium price.

If you are on a tighter budget and lower-speed internet plan, a modem with DOCSIS 3.0 would suffice.

DOCSIS 3.0 or DOCSIS 3.1 Modem?

Data over cable service interface specifications (DOCSIS) serve as the framework for exchanging data between your computer and the internet provider. The selection of DOCSIS standards influences how the modem is used.

DOCSIS 3.0 operates at a slower pace but boasts broader adoption, while the latest technology offers faster speed but at a higher cost.

With DOCSIS 3.0, you can attain speeds of 1 Gbps downstream and 200 Mbps upstream, which are commendable. Modems within this category are budget-friendly with prices ranging between $50 and $150.

DOCSIS 3.1 delivers significant speed advantages, boasting impressive rates of 10 Gbps downstream and 1 to 2 Gbps upstream.

However, it is worth noting that these high-speed modems come with a higher price, typically ranging between $120 and $300.

The optimal choice depends on your network needs and priorities. If you are content with your current speeds and not aiming for future-proofing, DOCSIS 3.0 could serve you well.

For DOCSIS 3.0 options, you might want to consider options such as the Motorola MB7220 and MG7540

On the contrary, DOCSIS 3.1 is the optimal choice for establishing a comprehensive home network that extends beyond standard internet use.

Consider scenarios where a media server, numerous computers, and many devices heavily rely on the network; the value of additional bandwidth becomes crucial.

For these setups, the Motorola MB8611 is a great Xfinity-compatible modem with DOCSIS 3.1 technology included.

Modem/Router Combo Vs. Separate Devices

Opting for a distinct modem and router offers customization and peak speed. Alternatively, modem-router combos suit simpler troubleshooting, setup, and cost efficiency.

How to Update Your Xfinity Router’s Firmware

Regularly updating the device firmware is recommended to ensure any bugs are removed and that you continue to experience quality internet connectivity.

To manually update the firmware, follow the steps below:

  • Find the maintenance tab.
  • Locate the Router Update section.
  • Click ‘check’ to automatically update the router’s current firmware.

While numerous modems are equipped for automatic firmware updates, occasional manual checks remain beneficial to ensure that your device has optimal performance.

Frequently Asked Questions

Is it possible to use a third-party modem with Xfinity?

Yes, it is entirely possible to use your modem with Xfinity services. Xfinity extends the flexibility for you to install and integrate your modem seamlessly while accessing its comprehensive internet offerings.

Can you install a replacement modem by yourself?

Yes, you have the autonomy to purchase a new modem, carry out the replacement, and perform activation independently. This removes the need for a technician to visit your residence.

Is it possible to plug and play the new modem?

No. Activation is an essential step before internet usage, regardless of whether the modem is sourced from Xfinity or is your personally owned device.

How to activate Xfinity Internet with your modem?

Activation of Xfinity Internet can be achieved via the app, website, or by contacting Xfinity’s technical support. The process involves a series of steps to verify and confirm account and device particulars.

Final Words

Hopefully, you’re now clear on the process of changing your Comcast Xfinity modem with your device.

This process is perfectly possible and provides you with the benefits of saving on rental fees while also enabling greater customization and security of the modem.

The process of changing modems is straightforward. You simply need to find a suitable device and use our step-by-step instructions to install the device.

Daniele Besana

Daniele Besana

Daniele is a freelancer consultant with 15 years of experience in network security, customer support, Linux and Salsa. He worked for Juniper Networks in Netherlands, providing support and consultancy on security projects across Europe and Middle-East.

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