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Practical Computer Advice
from Martin Kadansky

Volume 18 Issue 5

May 2024

Should You Continue Renting Your Internet Modem or Buy Your Own?

The Problem


If you examine the bill from your Internet Service Provider (ISP), you may notice a charge that you pay each month to rent the cable modem that they provide to deliver your internet service.


For example, Comcast (Xfinity) currently charges $15 each month to rent one of their regular cable internet modems, and if you have a higher level of internet speed you may be paying even more each month.


Note that any “TV boxes” that you might also be renting to get cable television service are completely separate from your internet modem, with separate charges.


You probably have the option of buying and using your own cable modem, which would only cost you a one-time charge instead of an ongoing monthly rental fee.


Is it better to rent a cable modem or buy your own?


Renting a cable modem from your ISP:


  • Pros: They provide support for the modem, so if there’s a problem you can contact them for help, troubleshooting, or even a replacement.
  • Cons: You will pay a modem rental fee each month.


Buying and using your own cable modem:


  • Pros: After the initial purchase cost there is no modem rental fee, so your modem will “pay for itself” over time. For example, buying a $120 modem to replace one that you’re renting for $15/month will start saving you money after 8 months.
  • Cons: You will have to buy a compatible modem, set it up, and deal with any problems or replacement costs.


How would you buy and use your own cable modem?


I recommend the following 6-step process:


1. Gather the following information:


  • What is your current wireless network name and password?
  • What is your current internet service speed in Mbps (megabits per second)? You can usually find this on your monthly bill.
  • On what day of the month does your billing cycle end?
  • What additional features does your current modem provide? The two most common are Wifi and landline phone service.


2. Compile a list of the makes and models of specific modems which:


  • You can buy on your own,
  • Are supported by your ISP,
  • That support your current internet service speed (or higher),
  • And that have the additional features that you’ll need, including built-in Wifi, extra ports for wired devices, landline phone service, etc.


Some ISPs (like Comcast) have a web page that may claim to list all of your choices, but in my experience these can be incomplete. Instead, I recommend contacting your ISP and asking them for a current list of all compatible third-party modems.


3. Research the current prices for each make and model on your list.


I’ve had good experiences buying “refurbished” (used) modems from reputable sellers, but you may not be comfortable with the potential problems that may come up.


4. After receiving your replacement modem, set it up:


  • Contact your ISP to tell them that you want to add (or activate) a new “owned” modem on your account, replacing the one you’re currently renting. If you called them on your landline or you used online chat through your internet connection, ask them to call you back on your cellphone since you’ll be unplugging your modem in the next step.
  • When they direct you, unplug your internet service’s coaxial cable from your old modem (which will temporarily disconnect all of your devices from the internet), and if you have landline phone service, unplug your landline phone from the modem as well. Set that modem aside, along with its power cable.
  • Connect your ISP coaxial cable to your new modem and plug in its power cable.
  • Tell your ISP the MAC address for your new modem so they can add it to your account and activate it. Your modem’s “Medium Access Control” address is a 12-character sequence of letters and numbers printed directly on it; it may have more than one.
  • If your new modem has Wifi, set that up as well, ideally using the same network name and password as your old modem.
  • Reconnect your wireless devices to your Wifi network - Windows and Macintosh computers, iPhones, iPads, Androids, shared network printers, smart TVs, etc.
  • Test your internet connection by checking your email, loading web pages, printing to your wireless printer, etc.
  • If you have landline phone service, plug your landline phone into your new modem and confirm that you can make and receive calls.
  • Take 1-2 weeks to confirm that everything works properly.


5. If your ISP requires it, return your old rented modem.


Ideally, you would do this before the end of the current billing cycle.


6. Next month, confirm that the modem rental fee has ended.


Additional things to consider


Before buying a used modem, confirm with the seller that they’ve removed it from their ISP account.


Since it has probably been many years since you set up the old modem that you’re replacing, I also recommend replacing its surge protector. Or, if you’re concerned about power outages, get a UPS (uninterruptible power supply) for both your modem and your wireless router.


Consider also getting a spare modem in case something goes wrong with the primary one, especially if you’re running a business.


Comcast doesn’t let you have two owned modems on the same account. This would only affect you if you had one owned modem already providing one service (e.g., your landline) and you wanted another owned modem to deliver another service (e.g., your internet). If this describes your situation, ask your ISP first if they have a similar restriction.


Other modem replacement scenarios


You might also find yourself:


  • Replacing a rented modem with another rented one: It might be time to get a newer and faster model, or solve a problem with your current one.
  • Replacing an owned modem with another owned one: Similar reasons.
  • Replacing an owned modem with a rented one: You might be tired of dealing with modem problems or replacements on your own.


If you’re selling or giving away an owned modem, be sure to have your ISP remove it from your account to eliminate a possible problem for your buyer or recipient.


What about FiOS (fiber optic) internet service?


FiOS (fiber optic) internet service providers like Verizon don’t use cable modems.


Instead they use their own company-supplied Optical Network Terminals (ONTs), which require installation by a technician. As a result, you cannot buy and use your own ONT.


However, you can choose to use your own wireless router instead of using one of theirs, but whether that will save money depends on whether your ISP charges a monthly fee for using their router.


Where to go from here


As always, if this seems too difficult to achieve on your own, I recommend that you find someone you know and trust to help you. In some of the searches below, replace “X” with the name of your ISP, e.g., Astound (formerly RCN), AT&T, Comcast/Xfinity, Cox, Spectrum, etc.


How to contact me:

email: martin@kadansky.com

phone: (617) 484-6657

web: http://www.kadansky.com

On a regular basis I write about real issues faced by typical computer users. To subscribe to this newsletter, please send an email to martin@kadansky.com and I'll add you to the list, or visit http://www.kadansky.com/newsletter

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I love helping people learn how to use their computers better! Like a "computer driving instructor," I work 1-on-1 with small business owners and individuals to help them find a more productive and successful relationship with their computers and other high-tech gadgets.

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