Why rent when you can buy?
Almost all cable companies are charging at least $5 a month to rent a cable modem from them. Comcast is now charging $10 a month in many areas. That's $120 a year or $600 in just 5 years. With new modems costing as little as $60 and used ones as low as $40, it makes sense to buy your own modem.
It's so simple to find a cable modem and set it up.
Just select your cable company from the list on the left or click on a tab at the top of this page.
We'll show you all the modems that are approved by your cable company to work on their system and are available through Amazon, Walmart or Best Buy. These modems are all approved by the cable companies as of September 2015. When you get your new modem, just hook it up, plug in a computer, open a browser and a page should appear instructing you on how to authorize your modem. In some cases, you'll need to call your cable company and give them the MAC address of your modem, which is located on a label on the back of the modem. Either way, a few minutes of your time can save you hundreds of dollars.
Cable Modem Buying Tips and FAQ's
Note for customers with telephone / internet bundles: For many cable customers, if you have your telephone service through your cable company, and paid to your cable company, these modems will NOT work for you. Comcast / Xfinity Voice and Triple Play customers in some regions can buy their own eMTA modem which will handle telephone and internet. Read here for further information: Comcast Voice Modems.
Time Warner / Brighthouse / Road Runner customers can buy a separate modem for internet and have their rental fees waived for their telephone modem. Read here for further information: Time Warner, Road Runner and Bright House telephone customers).
If you have an internet phone service such as Vonage, Magic Jack and other VoIP services, these WILL work. For others with phone service through their cable company, please read our review of a cheap alternative that we use both at work and at home, and highly endorse: Callcentric VoIP Phone Service.
Buy vs Rent
If you buy, you can save anywhere from $60 to $120 a year depending on your current and future rental fees. Cable companies have been raising rental fees recently and will continue to do so. If you rent, you aren't responsible if anything goes wrong, just return the modem for another one.
New vs Used
You can save even more money buying a used modem. Just make sure that you buy it from a reputable dealer with a good return policy and warranty. Watch out for some EBay sellers and other used dealers. They could be selling modems that were rented by ex-customers of cable internet providers and never returned. If this is the case, your cable company will notice this when you hook them up and won't authorize their use.
DOCSIS 2.0 vs DOCSIS 3.0
DOCSIS is a standard for cable modems that makes it possible to buy modems from retailers other than the cable internet provider. DOCSIS 3.0 is the latest and allows for extremely fast upload and download speeds. It works by combining (or bonding) multiple upload and download channels, making it multiple times faster than DOCSIS 2.0. DOCSIS 2.0 is the old system being phased out. It provides enough speed for viewing videos, gaming and other internet activities. DOCSIS 2.0 has a maximum speed limit of 38 MBit/s, while DOCSIS 3.0 has no maximum speed limit. All cable companies recommend buying a DOCSIS 3.0 modem. If you want to make sure you have a modem that will work for years to come as internet companies provide faster and faster service, buy a DOCSIS 3.0 modem. DOCSIS 3.0 modems will work on DOCSIS 2.0 systems, but with no speed increase.
For DOCSIS 3.0 technology, channels are like traffic lanes. Each channel can theoretically carry 42.88 Mbit/s (38 Mbit/s in the real world) of data or internet traffic. With DOCSIS 3.0, these channels can be bonded together like a multi-lane freeway to get multiple times the amount of data through. To calculate the amount of data that a modem can move, multiply the number of channels by the data rate for one channel. Usually we're only concerned with the number of download channels because most people are downloading a lot more data than uploading.
Price! The Main Deciding Factor
All of these modems are reliable and built to last for many years. There is very little difference between them, except for a few with built-in wireless routers. Price should be your first factor in deciding which one to buy.