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I’ll start by giving you a scenario.
Let’s say a couple is moving to a new home in a different area. As a result, they have a new provider for their internet connection.
On moving day, they pack up everything they own and move it to their new home.
At the new house, they quickly unpack and realize one of the first things they want to do is set up is their internet. They thought ahead and paid for a plan with their new internet service provider (ISP), so everything should be in place.
They plug in their internet equipment and follow the steps to set up their internet connection. It’s at this point that it all comes grinding to a halt.
How can this be?
Their modem worked in their old place. Why wouldn’t it work now?
Isn’t a modem compatible with all ISPs?
Modems are not compatible with all Internet Service Providers. A modem will not be able to establish an internet connection if it is connected to an ISP it is not compatible with.
If reading this information makes you nervous, don’t be alarmed.
In this post I’ll break down why your modem may not be supported by your ISP. I’ll also explain how you can verify what ISPs your modem supports.
Can I Use My Modem With Any Internet Provider?
You may be surprised to hear that your modem isn’t like your other electronic devices. You can’t just plug it in and expect it to work.
In fact, your modem isn’t even like your router. Although your router will work no matter who your internet service provider is, your modem may not.
Your modem will only work with a given set of ISPs. As a result, you need to be really careful when picking out a modem.
As you read in our example above, this often comes into play if you’re moving and have to switch your ISP. Your new ISP may not support the current make and model of modem you have.
So what do you do?
Thankfully, there are a few easy ways to make sure your modem is compatible with your ISP. We’ll get into those later.
Why Wouldn’t My Modem Work With My Internet Provider?
If your modem doesn’t work with a given ISP, there are two main reasons why that could be the case. Let’s take a close look at both of them so you know what you need to be aware of.
Your ISP Provides a Different Type of Internet Connection
The first reason why your modem won’t work with your ISP is if your ISP provides a different type of internet connection.
There are multiple ways to connect to the internet. Some of the most common ways include:
These different ways of connecting to the internet make the internet available to most people. At the same time, it can complicate things.
For example, you need to make sure your modem is compatible with the type of internet connection you have.
If you have a cable internet plan, you need to make sure your modem is built for that. You won’t be able to connect your modem to the internet if you have a fiber internet connection but your modem is built for cable internet.
Your Modem Is Not Supported by Your ISP
The other potential reason your modem won’t work with your internet provider is if they don’t support your modem’s make and model.
I was actually surprised when I first learned this.
The bottom line is, internet service provider’s can’t support every modem. They need to be selective about which ones they support.
This is because your ISP is responsible for updating your modem’s firmware for you.
Before they’re able to push updates to your modem, your ISP needs to test them to make sure the update doesn’t mess anything up with your internet connection.
They need to do this every time a firmware update is released for a given modem. Depending upon the modem, firmware updates may be released multiple times per year.
For your ISP, they can’t afford to perform all these tests for every modem on the market. It would be too expensive for them.
So what do they do?
They support the modem models that are the most popular.
That’s why if you have a modem that’s not a common make or model, it may not be supported by your ISP.
The same goes for older modems. If your modem is old, the chances are less likely that your internet provider will support it.
In fact, if a modem is old enough, the modem manufacturer will stop providing updates for it. When your modem’s manufacturer isn’t supporting your modem anymore, you should get a new one anyway.
That’s a topic for another time.
How to Tell What Type of Modem You Have
Let’s revisit the type of internet connection your modem supports.
What if you’re not sure what type of internet your modem is made for? How can you figure it out?
The good news is, it shouldn’t be hard to determine.
Let me start by saying most modems are made for cable internet. In 2021, over 194 million people in the United States had cable internet connections.
In other words, chances are you have a cable modem and cable internet connection.
Don’t take my word for it though. You should check for yourself to make sure you don’t make the wrong decision about your internet plan.
For one, fiber internet has become increasingly more popular. It’s also possible you have a DSL modem, even thought DSL is an older internet technology.
With all these options, it’s better to find out for sure what your modem is made for.
There are two easy ways to figure it out.
Look at the Ports on the Modem
The easiest way to tell what type of internet connection your modem has is to simply look at your modem.
If you look at the back of your modem, it’ll probably give you the answer you’re looking for.
The first thing you have to do is find the wire that provides your modem with an internet connection. Feel free to unplug the cable to get a closer look at a time when you’re not using your internet connection.
If that cable is a coaxial cable that looks like the one that plugs into your cable box, you have a cable modem.
If it’s a phone cable, you have a DSL modem.
Lastly, if it’s a fiber optic cable, you have a modem built for a fiber internet connection.
Still aren’t sure?
If you can’t tell just from looking at the cable, look at the port it connects to on your modem. It may be labeled with the type of internet connection it’s made for.
For example, here’s the back of my CM600 modem.
It says right on the back of my modem that it’s for a cable internet connection.
It doesn’t get much easier than that.
Unless of course you know the make and model of your modem. If you know what model your modem is, you can find out what type of internet connection it’s for without getting off the couch.
Look at the Modem’s Product Page
The other way to find the type of connection your modem is for is to look it up online.
The product page for your modem will tell you all you need to know.
Before we go any further, let’s make sure you know what your modem’s make and model is. To do this, just look at the sticker on your modem.
Check the bottom of your modem. That’s where the sticker is usually located.
The sticker will provide you with your modem’s model, as well as its manufacturer.
Here’s the bottom of my modem:
The manufacturer of my modem is Netgear, and the model is CM600.
Surprisingly, you can even see that it identifies my device as a cable modem right on the sticker.
I don’t need to go any further. I know my modem is built for cable internet. For the sake of this exercise I’ll continue the process in case the sticker on your particular modem doesn’t provide what type of internet it’s for.
Now that I know I have a Netgear CM600 modem, all I have to do is search for its product page online.
This lead me to Amazon’s product page for my modem. The product page gave me exactly what I was looking for:
The product page clearly identifies that my CM600 modem is for cable internet plans.
At this point my search is over. I’ve confirmed that my modem is made for an ISP that provides cable internet.
How to Look up the Internet Providers That a Modem Supports
What if you have a modem and you want to find out what ISPs it works with?
There are two ways to go about answering this question as well. One option is to go back to the product page for your modem that we were looking at earlier. Another option is to go directly to the source, which is an ISP’s website.
Look at the Internet Provider’s Support Page
Let’s say you want to find out if a specific ISP supports your modem. There’s no better place to look than the provider’s website.
Although you can also look at your modem’s product page, going to the ISP’s website is more reliable. Depending upon the product page you’re looking at, sometimes you might not get the most accurate information.
Anyway, back to the task at hand.
As I mentioned earlier, your internet provider is responsible for updating your modem for you.
As a result, ISPs will usually publish a list of the modems they support on their website. That’s because they don’t want their customers to have to guess what modems will work with their internet plan.
In the end, internet providers want you business. They want you to get a modem that’s supported by their internet plans so you don’t leave them for their competitor.
So where exactly do you need to look?
The best place to look is the support page. We’ll use my ISP as an example.
Accessing the ISP’s Support Page
I have a cable internet plan with Xfinity by Comcast.
I start by firing up my internet browser and navigating to Xfinity’s website. In a few clicks I find myself on the Internet Support page.
On the Internet Support page, there are a few headers to choose from. The one that stood out to me was “Using Your Own Equipment”.
I want to see if my personal modem is supported by Xfinity, so this header made sense to me.
When this section expanded, I saw the article I was looking for. I figured “Approved Equipment for Xfinity Internet and Xfinity Voice” was a good place to start.
After accessing this article I found a page that required me to put in my address and the speed of my internet plan. Once I entered this info, I was given a list of modems that Xfinity supports for my internet plan and geographic location.
Low an behold, I found my Netgear CM600 on the list.
This confirmed that Xfinity supports my modem. Of course I already knew this because I have a working internet connection, but these are the steps you’d need to follow if you want to check if an ISP supports your modem.
I did a few searches of common ISPs and it looks like all of the largest providers have lists of the modems they support.
Look at the Modem’s Product Page
The other option for looking at what internet providers are compatible with your modem is to go back to your modem’s product page.
To do this, follow the same steps that I detailed above.
I’ll use my modem as an example again.
Looking at information about my modem, it states the major ISPs it’s compatible with.
As you can see, my Netgear CM600 is compatible with Xfinity, Cox, and Spectrum.
Does this mean those are the only ISPs it’s compatible with?
Those are just the major providers that support my modem. If there’s a smaller, less well-known internet provider in your area, go to their support page or call them to see if they support your modem.
It’s possible that your modem is compatible with a smaller ISP. It just doesn’t make sense for a seller to list all the internet providers that are compatible with the modem on the product page. The list could be endless.
How to Ensure Your Modem Is Compatible With Your ISP
Does the information above overwhelm you? Would you rather not have to worry about your modem being compatible with your internet provider?
If this is the case, there’s an easy way out for you.
That’s to rent your modem directly from your internet provider.
If you rent a modem from your ISP, you know it’ll be compatible with their internet connection. It wouldn’t be very smart of them to rent you a modem that doesn’t work with their internet.
Although this is the easiest method for finding a compatible modem, it comes with a few drawbacks.
The first is that renting a modem will cost you more money in the long run than buying your own modem. When you rent a modem you’ll be charged a monthly free from your ISP.
In some cases, it can cost as much as $15 per month (or more) to rent a modem. Compare that to buying a modem where a good one will run you $100 or less. It’s easy to see that a year of renting a modem can be more expensive than buying your own.
On top of that, when you rent a modem you don’t get to choose what model it is. This might not give you the best internet performance because your modem won’t be specific to your individual internet plan.
Buying your own modem allows you to find one that fits your specific needs.
That’s not to say that renting a modem won’t give you a fast internet connection. That’s still possible if you rent. You just might not squeeze every bit of speed from your internet plan.
With all that said, if you’re willing to sacrifice a little bit of performance and pay a little bit more, renting a modem can be a convenient option. Especially if you get stressed out about trying to find a modem that’s compatible with your ISP.
Many people have made the mistake of getting a modem that isn’t compatible with their internet service provider. In reading this post you’ve ensured you won’t be one of them.
If you have any questions about this information or you’d like to share you personal story, I’d love to hear from you in the comments section below.
If you found this post helpful, check out some of the other useful posts that I’ve written: