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This post includes the five best Cable modems for Comcast’s Xfinity Internet service that you can confidently buy today.
All of these modems are approved by Comcast’s Xfinity Cable Internet service and tested with this service. However, you can also use them with other Cable internet service providers (ISPs), such as Spectrum or Cox.
I picked these modems after ongoing long-term experiences via my personal use and those of friends, family members, or business partners. All are excellent in their own right and are still working today.
Pick one for your Cable connection and a router or mesh system in one of the best lists in the box below, and you’re game. I can almost promise that.
Top five best cable modems for Xfinity: The list
I list these modems in the speed-grade order, starting with the slowest. Each will work well for the designated plans‘ speed.
It’s worth noting that Comcast Xfinity tends to provision cable connection download speeds with some 20% higher than the plan. As a result, it’s best to get a modem that can handle more than your plan. And that’s also my idea behind building this list.
For more on each modem, check out the in-depth review.
Top 5 best cable modems
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| Name | Netgear CM2000’s Rating | ARRIS Surfboard S33’s Rating | Motorola MB8600 DOCSIS 3.1 Cable Modem’s Rating | Netgear CM1000’s Rating | Netgear CM600’s Rating |
| Price | – | – | – | – | – |
| Rating | |||||
| Description | |||||
| Statistics | |||||
| Buy this product |
1. Netgear CM600: A valuable modem for Xfinity’s Fast (400Mbps and lower)
The CM600 has been around for a long time and is the only DOCSIS 3.0 cable modem on this list. It’s affordable and never failed me during a 5-year-and counting of service.
Technically, it can handle up to 960Mbps of download speed, but it’s best to use it with any plan that delivers 600Mbps or slower.
Netgear CM600's Rating
Pros
Fast and reliable performance for sub-Gigabit broadband
Supported by multiple cable providers
Affordable and relatively compact
Clear status lights, useful web interface
Cons
No Gig+ or Multi-Gig support
No WAN Link Aggregation
2. Netgear CM1000: An excellent Cable modem for Xfinity’s Superfast (800Mbps and slower)
The Netgear CM1000 is a DOCSIS 3.1 and can handle faster-than-Gigabit cable connection. However, it has a Gigabit port which is the bottleneck.
Technically, you can use it for a Gigabit cable plan. However, because a Gigabit port has overhead, the modem can only sustain at a slower-than-Gigabit speed, though only by a small margin.
We’ve used this modem for over two years with no issues.
Netgear CM1000's Rating
Pros
Fast and reliable performance, with up to 1Gbps of broadband speed
Supported by multiple cable providers
Relatively compact with clear status light
Reasonable cost
Cons
Single LAN port, no WAN Link Aggregation
The base is a bit flimsy
3. Motorola MB8600: Another excellent option for Xfinity’s Superfast with an option for 2Gbps link aggregation
The Motorola MB8600 is an interesting cable modem.
On the one hand, it’s an excellent option for a sub-Gigabit plan, like the Netgear CM1000 above; on the other, it has additional LAN ports that can be combined into a 2Gbps Link Aggregation WAN connection for a supported ISP.
We’ve used this one—in the former role—for almost two years with no issues at all.
Motorola MB8600 DOCSIS 3.1 Cable Modem's Rating
Pros
Fast and reliable performance
Clear status lights
DOCSIS 3.1
Supported by multiple cable provider s
Optional WAN Link Aggregation and multi-Static-IP support
Cons
No Multi-Gig network port
A bit bulky
4. ARRIS SURFboard S33: The compact option for Xfinity’s Gigabit Extra (1200Mbps) and faster
Supporting DOCSIS 3.1 and having a 2.5Gbps LAN port, the ARRIS SURFboard S33 is an excellent Cable modem for those with a super-fast Internet plan.
I’ve used it for over a year—since my review—with no issues.
ARRIS Surfboard S33's Rating
Pros
Fast and reliable performance, up to 2.5Gbps of broadband speed
Compact and nice-looking design
Can handle two status IP addresses
Easy to set up
Cons
Cryptic, impractical single-status light
Runs a bit hot
Terrible mobile app
No WAN Link Aggregation
5. Netgear CM2000 Nighthawk: The full-size option for Xfinity’s Gigabit Extra (1200Mbps) and faster
Similar to the ARRIS SURFboard S33, the Netgear CM2000 can deliver up to 2.5Gbps of download speed, making it an excellent Cable modem for Xfinity’s fastest plan, the Gigabit Extra, which, in my experience, can deliver 1.5Gbps of download speed.
I’ve used it for almost two years as my personal modem. Initially, it was the only Internet source for my home. Since March this year, when I upgraded to a 10Gbps Fiber-optic plan, I’ve kept it as a secondary connection in a Dual-WAN setup.
It’s been an excellent modem with no issues at all.
Netgear CM2000's Rating
Pros
Fast and reliable performance, up to 2.5Gbps of broadband speed
Supported by multiple cable providers
Relatively compact with clear status light
Comprehensive web interface
Cons
Expensive
Single LAN port, no WAN Link Aggregation
The final thoughts
When using Cable Internet, I recommend getting a retail modem and a separate router or mesh system.
I detailed all the reasons in this post on how to activate a new cable modem. But among other things, you’ll get faster connection speed, avoid the monthly hardware rental fees, enjoy better privacy, and have much better flexibility in picking which equipment to use in case you want to change or upgrade.
After that, it never hurts to get the fastest Cable modem available—so it’s always safe to pick the Netgear CM2000 or ARRIS SURFboard S33 above.
However, unless you intend to upgrade your broadband speed later, getting a modem faster than your Internet plan is always a waste of investment.
Hello,
I recently upgraded to spectrums internet gig with speeds up to 1000Mbps. I also purchased a new router (RT-AX86U PRO).
What modem would pair best with my current setup? I would also like to extend the range of the WiFi throughout my home. Would it be practical to add a mesh system?
Thanks in advance.
You can get any modem with a 2.5Gbps port, Jorge. The RT-AX86U Pro has only one 2.5Gbps port, it can host a Gig broadband line (with full bandwidth) but you won’t be able to have it on the receiving end due to the fact it only has Gigabit ports left and Wi-Fi is generally finicky—more here. As for extending the system, check out this post on mesh and related ones in the same series.
Would love to see this updated to include review on the latest Nighthawk CM3000 and your opinion as to whether its worth upgrading from CM2000 to CM3000 for the synchronous upload speeds.
According to my xfinity app the cm600 is “no longer supported” by xfinity. It is March 2023.
Thanks for the input, LD. I guess Comcast is phasing out DOCSIS 3.0 and no longer accepting new activation. The one we have still worked with no issue or warning. Maybe it’s just a matter of time.
The Netgear CM1000 (DOCSIS 3.1) also doesn’t seem to be supported. The only Netgear modem that seems to be supported is the CM2000. I have a SMC1604 that is still working but gets only about the half the speed it should. (Supposed 150/20 plan) Any suggestions for an inexpensive modem that Xfinity will support?
I’ll answer my own question. Hitron Coda is recommended by Xfinity and is under $100. Doubled upload and download speeds from my son’s Docsis 3.0 modem. Easy setup and so far works great. Hopefully it stands the test of time. Good for up to
900+Mbps.
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I haven’t tested it but it looks like a good deal if it holds up well. Good luck and keep us posted! Thanks for sharing, Mark.
Note: The product link goes to the Hitron Coda 56, not the Coda. For whatever reason the 56 is not recommended by Xfinity. It is compatible however. Looking at customer reviews, the 56 seems less reliable. The Coda is listed at $99.99. Also interesting. I’d been looking at the Coda on Amazon for awhile and a $15.00 limited time discount popped up.
Hi Dong,
I was never able to get fiber in my area (and they aren’t planning on it), but it looks like Xfinity is finally rolling out 10G. Looks like I need to upgrade my CM2000!
I’d wait to see how it pans out first. You can’t take what Comcast say at the surface and currently there’s no modem that can deliver 5Gbps or faster.
Thnx Dong for the info, very very helpful.
I’m in the process of upgrading my modem with Xfinity since they just changed out the fiber in our neighborhood. I’d also received an e-mail from them stating my current modem (Arris SB6183) will not be compatible very soon because of filters. Not sure what that means other than they mentioned I have higher megabit speeds available and my modem limits that. Anyway, am considering the S33 now based on lots of reading and mainly this sites recommendations.
Any current known issues with it on Xfinity from anyone this February? I know about the heat issues, won’t be affecting me since it’s out in the open but what about firmware or updates recently pushed out from Xfinity. I’ve read about nightmares for some people mainly with Motorola 8611’s but not with Arris.
any help would be appreciated since I’ve got an S33 loaded in my cart with Amazon. 🙂
thnx in advance
The S33 will work great, Joseph. We’ve been using three units at different locations with Xfinity with no issues. The only problem I have with it is the single status light which can be annoying when you need to troubleshoot. Give the short review a look for more. Other than that, I’d say go ahead.
Hi ,
Will S33 work good with google nest mesh wifi ? Is it recommended ? Please advise.
Thank you for a great review.
All modems will work with all routers or mesh systems, Pooja, as long as they use standard network ports (which the two you mentioned do.)
I’d not recommend Google Nest Wifi, though, but that’s a different story.
An addendum to previous post. I did read your reviews of available modems and was looking at the Arris s33 but I’m usure about the Wi-Fi 6 question.
A modem and a router are two different things, George. This post will help you become less confused.
On Xfinity if you use your own modem and use over 1.2 TB then you must pay $30/month for unlimited data. There is no cap if you use Xfinity’s $25/month modem. So it’s actually cheaper to use a rented modem. Do you have any opinion on the Xfinity modem, or why they have these plans priced in this manner?
Yes, I mentioned that in the post on how to activate a modem, Bill. Most of the time you won’t use more than 1.2TB/month, though, and you can do that twice a year with no penalty. Xfinity doesn’t have any modem, it only offers the gateways. As for the reasons, a gateway allows the ISP to collect your information to sell to advertisers — more in this post.
Thanks Dong for the continued (and helpful) content. I would love to switch out my Xfinity modem, but I am not sure if Xfinity Home will work without their XB7 modem / router. Calls to them and searches have come up short of finding an answer.
It’ll work fine unless you also have phone service with them. In this case, you need a modem with phone capability. More in this post.
Thanks Dong! Now I am flipping the switch completely and thinking about just making the switch to Fiber from Xfinity – the only issue is finding a competent home security system.
Good move, Joey! There are a lot of options on the security front and they all work well with any ISP (the faster is always better anyway.)
Using the Motorola MB8611 here as well, after encountering some occasional disconnects with the Arris G36. So far the MB8611 has been solid, but it’s only been running for a week. We’ll see how it goes.
It’ll hold. 🙂
Wish ours was. We no longer have reliable Wi-Fi – keeps dropping in & out, with no trouble indicated by its status lights – beyond the room the modem & router are in. Had the same modem for years until it was no longer supported by Comcast so we “upgraded” to this. Unfortunately, I see the exact same issues in Amazon reviews for the Nighthawk and Arris.
Sorry to hear what you’re experiencing but from what you said, your issue likely had *nothing* to do with the modem, Julie. Internet and Wi-Fi are two different things. Chances are you don’t know that. If so, you’re not alone. Give the linked post a good read, and maybe you can figure things out.
I’ve been using the same Motorola model for about 15 months with no hiccups. We pay for the Comcast 600MB tier but get significantly better at 1.44gb down.
You can’t get over Gigabit with that modem, Dave. 🙂
But thanks for sharing the experience.
Re: Motorola MB8600
I had the big brother Motorola MB8611 which has a 2.5Gbps port. No issues. And it had the “Certified for Comcast Xfinity” sticker.
…and then I was able to switch to Fiber 🙂
Fiber is much better for sure. I keep both, for now. 🙂