The 9 Best Cable Modems
Updated by · How we research
Skip DOCSIS 3.0. We compared nine DOCSIS 3.1 modems by plan speed, Ethernet ports, upload support, ISP approval and price. The Arris Surfboard SB8200 leads. When users buy our independently chosen editorial picks, we may earn commissions to help fund the Wiki.
Owning a cable modem ends the monthly rental fee, and a DOCSIS 3.1 model costs little more than an older 3.0 box, which some providers are reportedly phasing out. The modem connects your home's cable line, from a provider such as Xfinity, Spectrum, Cox or Sparklight, to your Wi-Fi router. None work on fiber or DSL.
Editor's Notes
October 17, 2026, by Ezvid Wiki Admin:
The cable world has moved on from DOCSIS 3.0, the standard behind three of the old picks: the Motorola MB7621, the Netgear CM600 and the Netgear CM500V. A modem retailer reports that Spectrum is dropping DOCSIS 3.0 support and Xfinity is pulling 3.0 models off its approved list. We couldn't confirm the dates with either company, but a DOCSIS 3.1 modem costs little more, so we wouldn't buy a 3.0 model now. The Netgear CM1150V went too. It's an Xfinity voice modem for a narrow bundle.
The Arris Surfboard SB8200 takes first place as the most widely approved modem we found, and it has two ports. The Motorola MB8611 stays as the value pick for faster plans, and the Netgear Nighthawk CM1000 stays for gig plans.
Most of the new entries are about speed headroom. The Arris Surfboard S34, the Netgear Nighthawk CM3000 and the Netgear Nighthawk CM2500 support the wider upload band providers are starting to sell. The Arris Surfboard S33 and the Hitron CODA56 add 2.5-gigabit ports. For readers who'd rather have one box, the Netgear Nighthawk CAX30 is the lone modem-router combo.
Many readers ask how the Motorola MB8600 compares with the Netgear CM1000. The MB8600 isn't sold new anymore, and its successor, the MB8611, adds a faster port for less money.
One caution. We found no independent lab tests of these modems. Speed ratings come from makers' spec pages, approvals from the providers' own lists, and reliability from owner reports. Your line quality matters as much as the box.
January 07, 2021:
First of all, make sure to check with your specific ISP to ensure that the modem you choose is compatible. For what it's worth, the majority of up-to-date modems will be compatible with many modern ISPs, but some have specific requirements that a few otherwise-good modems don't quite meet. You can almost always find a list of approved modems on your ISP's website.
There hasn't been a whole ton of advancements in modem technology recently, but there has been some. We did replace the Motorola MB8600 with the Motorola MB8611, which is newer and only a hair more expensive, while also being significantly more advanced.
Otherwise, we moved the Motorola MB7621 to the top spot due to its impressively low price and its two-year warranty, which surpasses that of others with similar prices and performance. We also eliminated the Netgear CM500, because it's no longer very much less expensive than many of the faster options.
April 02, 2019:
First of all, if you're in the market for a cable modem, there are two things you should generally avoid buying. One is a combination modem and router. They are generally much more problematic than separate devices because they can't be provided with the same firmware updates that many routers require over their lifespan, and they don't even really save you any money. The second is a 32x8 channel DOCSIS 3.0 modem, as these are run by what's called the Intel Pump 6 chipset, which has exhibited a fatal flaw that causes troublesome latency spikes and disconnects. It's been this way over the entirety of the chipset's lifespan (nearly two years), so there's no reason to believe that Intel will be rolling out a fix anytime soon. Finally, if you don't plan on upgrading to gigabit-class service in the forseeable future -- and most people in the USA don't even live in regions that offer it, nor will most of the rest of us ever need that kind of bandwidth -- then you probably don't need to shell out big bucks to be an early adopter of DOCSIS 3.1. If you're into future-proofing your setup, though it is something to consider.
With that out of the way, if you're on a budget and don't plan on streaming multiple 4K videos at the same time while someone else is playing games, the Netgear CM500 base model may be your best bet. The Motorola MB7621 is only a bit more expensive, though, and can provide upgraded performance, especially for networks with a lot of users. On the other end of the spectrum, the Arris SurfBoard and Netgear's CM1000 and CM1150V provide next-level DOCSIS 3.1 functionality in addition to exceptional DOCSIS 3.0 backward compatibility, though they are considerably pricey. Plus, Netgear's voice-enabled modems are generally limited to the Comcast Xfinity phone+cable bundled packages. In the middle of the performance range are the TP-Link and Motorola's higher-end unit, but the Netgear CM600 may be the best of the bunch (for most users, anyhow), simply because it provides excellent real-world speeds at notably reasonable price.
Check Your Provider And Plan First
Above 1 gigabit, you want a 2.5-gigabit Ethernet port, and your router needs one too, or a modem with two gigabit ports and a router that can bond them.
A modem only works if your cable company agrees to activate it, so start with your provider's approved list. Xfinity has a lookup tool for customer-owned devices (Xfinity). Sparklight, the Cable One brand, requires a DOCSIS 3.1 modem and publishes a separate list for its multi-gig tiers that names the Arris Surfboard S33, Hitron CODA56 and Motorola MB8611 (Sparklight). Activation usually means giving the provider the modem's MAC address or serial number, online or by phone.
Then match the modem to your plan. For any plan up to 1 gigabit per second, a DOCSIS 3.1 modem with 32-by-8 channel bonding and a gigabit port is plenty. Above 1 gigabit, you want a 2.5-gigabit Ethernet port, and your router needs one too, or a modem with two gigabit ports and a router that can bond them. A faster modem won't speed up a slower plan.
Avoid DOCSIS 3.0 models, even cheap ones. ModemGuides, a modem retailer, reports that Xfinity began removing DOCSIS 3.0 models from its approved list in 2026 and that Spectrum is ending support for them (ModemGuides). We couldn't confirm this on the providers' own pages, but the price gap to DOCSIS 3.1 is small. Also note that a cable modem works only on cable (coaxial) service. It won't work with fiber, DSL, satellite or 5G home internet, and none of these picks carry phone service.
Ports, Upload Speeds And What Comes Next
Ethernet ports set the ceiling on what reaches your router. A single gigabit port tops out around 940 megabits per second in practice, enough for gig plans. Multi-gig plans need a 2.5-gigabit port. Some modems, such as the Arris Surfboard SB8200 and the Netgear Nighthawk CM2500, offer two gigabit ports instead, which reach 2 gigabits only if the router supports link aggregation. A second port also lets a wired desktop or a backup router plug straight into the modem.
Upload speed is the newer battleground. Traditional cable systems carry uploads in a narrow band from 5 to 42 megahertz. Mid-split widens it to 85 megahertz and high-split to 204 megahertz, which lets providers sell much faster uploads (Light Reading). Arris markets the S34 for these next-generation upload tiers (Surfboard), and Netgear lists the CM3000 and CM2500 as mid- and high-split modems (Netgear). If you only pay for a modest upload, you don't need this. Some owners say the provider had to switch the faster upload mode on.
DOCSIS 4.0 is the next standard, and cable companies are trialing it. No modem on this list supports it, and you don't need it to get full speed from today's plans.
Motorola MB8600 And MB8611 vs. Netgear CM1000
Readers often weigh the Motorola MB8600 against the Netgear Nighthawk CM1000. The MB8600 isn't sold new anymore, so today the choice is between its successor, the Motorola MB8611, and the CM1000. Both are DOCSIS 3.1 modems that work with Comcast, Cox and Spectrum, and the difference is the port. The CM1000 has one gigabit port, plenty for plans up to a gigabit, and Xfinity customers can activate it online without a call, though Xfinity approves it only for slightly slower plans. The MB8611 has one 2.5-gigabit port, so it can run plans just under 2.5 gigabits if your router has a matching port, and it costs less. On a gig plan or slower, either one does the job.
Modem Or Combo, Savings And Security
A separate modem and router let you upgrade each one on its own. Wi-Fi standards change faster than cable standards, so a good modem can outlast two routers. A combo such as the Netgear Nighthawk CAX30 saves space and a power outlet, but when its Wi-Fi ages, you replace both parts.
Owning your modem ends the rental fee. By SpeedTestHQ's figures, a year of rental costs close to what a mid-priced modem does (SpeedTestHQ), so owning usually pays for itself in one to two years. Check your own bill first, since some providers have cut or bundled the fee.
You can't update a cable modem's firmware yourself. Your provider pushes updates to models it supports. That matters: in 2020, researchers disclosed Cable Haunt, a flaw in chipset software used by several modem brands that let attackers take over affected units remotely (Cable Haunt, NVD). Buying a current model your provider actively supports is the best protection. Give the modem open air, too: at least one owner of an Arris Surfboard S34 reported overheating in a closed cabinet. We checked every brand here with the U.S. Consumer Product Safety Commission and found no cable modem recalls (CPSC).
How we researched this
We compared 15 cable modems and modem-router combos and screened 10 in depth. We read makers' spec pages for the Arris Surfboard SB8200, S33 and S34 and the Netgear Nighthawk CM3000 and CM2500 (Motorola's and Hitron's sites wouldn't load for us, so those specs come from the product listings), provider approval lists from Xfinity and Sparklight, roundups from Tom's Guide, RouterFreak and SpeedTestHQ, and owner reports in Netgear's community forum, on Reddit and in listing feedback. We checked every brand for recalls with the U.S. Consumer Product Safety Commission. We found no independent lab tests of these modems.
Sources (15)
- Surfboard: SB8200
- Surfboard: S33
- Surfboard: S34
- Netgear: Nighthawk CM3000
- Netgear: Nighthawk CM2500
- Xfinity: customer-owned devices
- Sparklight: supported cable modems
- Sparklight: multi-gig supported modems
- ModemGuides: Spectrum modems no longer supported
- Light Reading: the upstream sweet spot with DOCSIS 4.0
- SpeedTestHQ: best cable modems
- RouterFreak: best cable modems
- Cable Haunt
- NVD: CVE-2019-19494
- CPSC recalls
Frequently asked questions
Motorola MB8600 vs. Netgear CM1000: which is better?
The MB8600 is no longer sold new. Its successor, the Motorola MB8611, adds a 2.5-gigabit port and costs less than the Netgear Nighthawk CM1000, which has one gigabit port. For a gig plan, the Arris Surfboard SB8200 is the steadier pick of the three.
What is the best modem for Cable One (Sparklight)?
Sparklight requires a DOCSIS 3.1 modem. Its multi-gig list names the Arris Surfboard S33, Hitron CODA56 and Motorola MB8611. Check Sparklight's support pages for the list that matches your plan.
Is a cable modem the same as a router?
No. A modem connects to your provider's line and gives you one wired connection. A router creates your Wi-Fi network and shares the connection. A modem-router combo does both in one box.
Do cable modems work with fiber internet?
No. Cable modems work only on coaxial cable service. Fiber, DSL, satellite and 5G home internet use different equipment, usually supplied by the provider.
What is the fastest cable modem?
Modems with a 2.5-gigabit Ethernet port, such as the Arris Surfboard S34 and S33, Motorola MB8611, Netgear Nighthawk CM3000 and Hitron CODA56, handle plans up to about 2.5 gigabits per second. Your plan sets the real speed.
How much does a cable modem cost, and does it pay off?
The modems on this list range from about the price of a year of rental fees to roughly twice that, so most pay for themselves within one to two years. The price shown with each pick is checked against current listings.
