The Best Cable Modem (2024)

Before joining Wirecutter as a senior staff writer, Joel Santo Domingo tested and wrote about PCs, networking devices, and personal tech at PCMag and PC Magazine for more than 17 years. Prior to writing for a living, Joel was an IT tech and system administrator for small, medium, and large companies.

If your ISP offers a modem or modem-router combo gateway for no charge, try it out. If it works well for you, great—you haven’t spent any money on it. If it doesn’t work well, come back and read the rest of this guide. (Optimum and Spectrum include the modem-rental cost in their current internet plans, but if you haven’t changed your plan in a few years, you may still be paying a rental fee. If you use Optimum or Spectrum service, give your provider a call to see what your options are.)

You should buy a cable modem if you currently pay a fee to rent one from your ISP. Most ISPs charge up to $15 a month to rent a modem—that’s $180 per year, every year, on top of what you already pay for internet access. Even if you spend $200 for your own modem, you’re still likely to save money in the long run.

Many ISPs rent out modems that double as wireless routers, otherwise known as internet gateways, modem-router combos, or modems with Wi-Fi built in. Whatever those devices are called, we don’t recommend them because cable modem and router technologies mature at vastly different rates. For example, the modem part of a modem-router combo you started using in 2018 is probably still fine today, but in 2024 you might need better coverage or speed than the Wi-Fi 5 router part of that combo device can provide. Also, if either portion of the combo device breaks, you have to replace the whole box, which can get expensive.

So if you replace your rental modem with one that you buy, you may also need to purchase a wireless router if you want Wi-Fi in your house. Our favorite Wi-Fi router currently sells for about $100. That puts your total up-front cost to replace your ISP’s modem-router combo unit at $300 or so. Your modem should last you at least five to 10 years; judging from our experience, we estimate that the router may need replacing after three to five years. (If you’re not sure what the difference is between a cable modem and a router, we have an article explaining that.)

Don’t buy a cable modem if you’re on DSL or fiber; those technologies use different standards and connectors. Verizon Fios lets you buy your own modem-router combo, but you have only a single choice, and it’s identical to the equipment the company rents to you.

You also shouldn’t buy a cable modem if you use your cable provider for telephone service: The models we cover here don’t have phone ports. If you need a modem that does, check to see which “telephony” or eMTA modems your ISP supports, and whether the company allows you to buy your own.

For example, Xfinity’s web page has a checkbox to help you determine which approved modems are voice/telephone enabled, and Cox offers a list of approved modems that are compatible with its voice services. Sparklight notes on its website that it supports just a handful of Arris modems (including the one it leases to you) for voice service. The telephony modems you can buy are also more expensive than regular cable modems.

If you own a cable modem that supports your internet plan’s top speeds, and if you’re happy with it, keep using it until your ISP stops supporting it and it stops working (the company will let you know with both an email and a letter in your mailbox).

You should get a new modem if yours doesn’t support DOCSIS 3.0 or 3.1, the most widespread iterations of the Data Over Cable Service Interface Specification, which governs how cable operators deliver high-speed cable internet. If you’ve had your modem for about 10 years, do a quick Google search on the model name; you might still be using a modem that supports only DOCSIS 2.0, in which case it’s time to upgrade.

In previous versions of this guide, our picks were DOCSIS 3.0 modems, which could handle plans offering speeds up to about 800 Mbps. In 2024, we recommend buying a DOCSIS 3.1 modem for a new installation, as such modems are more likely to have technical support going forward.

Contributors on the r/HomeNetworking subreddit have mentioned that ISP customer service representatives are now either strongly suggesting or outright requiring the use of DOCSIS 3.1 modems. We take such anecdotal reports with a grain of salt, but if you have a cable modem that’s too old, your ISP may stop supporting it—that is, it will stop working—because your ISP either can’t or won’t continue providing firmware updates from the modem manufacturer.

No publication really reviews cable modems—the task is difficult because the reviewer can’t know whether it’s the modem or the ISP that’s to blame for slower speeds—so the few reviews that exist aren’t very scientific. We don’t have the capability to test multiple modems on multiple ISPs ourselves, either.

Instead, we started our research by considering all the DOCSIS 3.0 and DOCSIS 3.1 modems that work on the nation’s biggest ISPs: Astound (RCN), Charter, Cox, Mediacom, Optimum, Sparklight, Spectrum, WOW, and Xfinity. We then narrowed the field to modems compatible with the most popular plans on those ISPs. (Astound, Optimum, and WOW don’t publish a list of approved modems, though, and with few exceptions they wouldn’t verify whether any of our picks would work with their services. If you have service with one of these providers, contact customer support to confirm whether your modem will work with the network.)

The Arris SURFboard S33 is a reliable DOCSIS 3.1 cable modem that is compatible with gigabit and multi-gigabit internet plans. It has a two-year warranty, so you can save on rental fees and still have your hardware covered for a decent amount of time. It’s less expensive than competitors, and as a DOCSIS 3.1 modem, it’s likely to last up to 10 years longer than cheaper, DOCSIS 3.0 modems.

It’s fast. The S33 is rated for 32x8 channels and DOCSIS 3.1, which means it is capable of internet speeds from 25 megabits per second (or whatever your ISP’s minimum is) up to 2,500 megabits per second (or 2.5 gigabits per second). Note that your internet speed is dependent on what plan you have: If you’re paying for a 300 Mbps plan, for example, that’s all the speed you can get from the S33.

Arris modems have an excellent compatibility track record. We’ve encountered a couple of DOCSIS 3.0 modems (the Arris SURFboard SB6190 and the Netgear CM700) capable of 1-gig speeds on a few ISPs (notably Sparklight and WOW), but those same modems are capable of only 500 Mbps to 800 Mbps on some other ISPs and aren’t supported at all on two. The Arris SURFboard S33 is certified for all speeds on every network aside from Mediacom, which supports it unofficially.

It should be compatible for years. These days ISPs are either recommending or categorically requiring DOCSIS 3.1 modems for both upgraded and new accounts. Though older, DOCSIS 3.0 modems are still compatible with some ISPs currently, that is not guaranteed for the future, not even for two to five years from now.

It’s small. The S33 is easier to hide (or ignore) than other modems, measuring about 5 by 5 by 2 inches. That’s similar to the dimensions of two 12-ounce soda cans side by side.

It’s less expensive than the competition. The S33’s main competitor is the Netgear Nighthawk CM2000, which has consistently been $50 to $100 more expensive than the S33 over the past few years.

Flaws but not dealbreakers

It’s more expensive than midtier modems. DOCSIS 3.0 modems such as the Arris SURFboard SB6190 and Netgear CM700 are cheaper. However, though you may be able to get up to 800 Mbps with either modem on Xfinity and 1 Gbps on Sparklight, both are capable of only 500 Mbps on Cox’s network and 600 Mbps on WOW, and Mediacom and Spectrum don’t officially support them.

We’ve read reports and reviews indicating that it runs a little hot. While that doesn’t disqualify the S33, overheating remains a concern. We recommend leaving any modem in the open with sufficient breathing room, not enclosed in a cabinet.

If Mediacom is your provider, you have to call to confirm compatibility. Online reports say that the S33 should work fine with that ISP, but it isn’t on Mediacom’s official compatible-modem list at this writing. The Netgear Nighthawk CM2000, in contrast, is on Mediacom’s list.

If you want to save some money and don’t plan on upgrading to a multi-gig internet plan: The Arris SURFboard SB8200 is a good alternative to our pick that may save you a few dollars. It is DOCSIS 3.1 certified, and it appears on all the approved modem lists we track. It has a two-year warranty and is worth considering if you find it priced $30 to $50 below the S33. It has Gigabit Ethernet ports instead of a 2.5 GbE port, but it’s entirely sufficient if you subscribe to a midtier (300 to 1,000 Mbps) plan.

If you absolutely must buy a cheap modem today: We still like our former budget pick, the Netgear CM500, as an option for the frugal internet user, with reservations. You can recoup its $60 price quickly in terms of the savings on monthly rental fees, and it is a reliable modem if your plan provides speeds of 200 Mbps to 300 Mbps at most. However, last year the CM500 dropped off Spectrum’s approved-modem list, and Xfinity demoted the CM500 from 300 Mbps support to 200 Mbps support on its official list. Although this model is still supported at Cox, Sparklight, and Xfinity right now, that could change at any time in the near future. DOCSIS 3.1 modems are almost certain to have support for years after the CM500.

Regardless of which modem you choose, you need to activate it once you get it. Each ISP has a different process, but you need to either call the company or visit a URL to activate your modem. Cox, Mediacom, Optimum (PDF), Sparklight, Spectrum, and Xfinity provide instructions on their respective websites, but you need to call WOW’s customer service line to activate your modem with that ISP.

Our former top pick and upgrade pick were both manufactured by Minim, a licensee of the Motorola brand. Minim has stopped selling new modems and has transferred its current inventory to Motorola. While these modems may still be available in refurbished or used condition, we strongly recommend that you not purchase Motorola-branded modems at this time. Though Motorola modems currently in use should continue to work, firmware upgrades may not be available in the future. If you currently own a Motorola modem, consider replacing it in the next year or two, or if your ISP advises that it will stop support for Motorola modems, whichever comes first.

We’re looking forward to evaluating the Netgear CM3000, a new DOCSIS 3.1 modem with dual one gigabit ports as well as a single 2.5 GbE port. The CM3000 promises faster upload speeds than older modems, but this feature depends on your ISP’s infrastructure upgrades rolling out this year and next.

DOCSIS 4.0 modems with 10 Gigabit Ethernet (10 GbE) ports are on the horizon. Our top pick features a 2.5 Gigabit Ethernet port, and some cable-modem customers can order 2 Gbps service today, but there is always the desire for faster speeds among early adopters and some home offices.

New Wi-Fi 7 routers such as the Eero Max 7 and TP-Link Archer BE800 come with 10 GbE ports, in anticipation of supporting the upcoming DOCSIS 4.0 modems. However, aside from a few early deployments in Atlanta, Colorado Springs, and Philadelphia, it’s likely to be a year or two until these speeds are widely available.

Although we’ve recommended Motorola routers in the past, nowadays no one can guarantee that you’ll be able to receive support or software/security updates for these devices. In the previous version of this guide, the Motorola MB7621 was our top pick, and the Motorola MB8611 was our upgrade pick; we mention them here only to note that if you currently own one of these models, we suggest that you continue to use it as long as your ISP supports it. We will continue to monitor Motorola and whether it relicenses its cable-modem business.

Like our pick, the Arris SURFboard S33, the Netgear Nighthawk CM2000 has a 2.5GbE port, which can connect to Wi-Fi 6, Wi-Fi 6E, and Wi-Fi 7 routers that support the 2.5 GbE standard. The CM2000 shows promise, but it is priced too high in comparison with the Arris S33. This model also has a shorter, one-year warranty, and Netgear charges for tech support beyond the first 90 days of ownership.

Other Netgear modems we’ve considered include the CM1000, CM1100, and CM1200. All three modems are DOCSIS 3.1, and like the Arris S33 and SB8200, they are rated for gigabit internet plans. The CM1000 is occasionally less expensive than the Arris SB8200, but like other Netgear modems, it has a shorter, one-year warranty. The CM1100 features two Ethernet ports, while the business-oriented CM1200 has four. The advantage of multiple Ethernet ports is that they can connect to multi-gig 802.11ax/Wi-Fi 6 routers that support link aggregation (in other words, multiple Ethernet cables connect the modem and router to support multi-gigabit speeds), but we don’t think most people are likely to use that feature anytime soon.

The Arris SURFboard SB6183 was a pick in 2017, and we reevaluated it against the Netgear CM500 since that model is similar in specs and price. However, the SB6183 has a note on Cox’s approved modems list to contact Cox to discuss upgrade options; that note does not bode well for the SB6183’s longevity. We also evaluated the Arris SURFboard SB6190 and Netgear CM700 as cheaper alternatives to our pick, but neither DOCSIS 3.0 modem had full 1 Gbps support from most ISPs.

The table above lists which of our cable-modem contenders work with which ISPs based on information from each provider. (Optimum and WOW don’t provide a list of compatible modems.) Where applicable, we also include in that table the maximum speeds each ISP supports. We didn’t include modem-router combos (aka gateways or modems with Wi-Fi built in) because we don’t recommend such models.

Note that some DOCSIS 3.1 modems advertise “up to 10 Gbps” speeds. This is the theoretical limit of the DOCSIS 3.1 standard, and such speeds are currently unreachable. You would need a router with WAN port aggregation or a 2.5/5/10 GbE port to enable speeds above 1 Gbps, and many ISPs currently list 1 Gbps as their top speed tier for residential customers (plans offering 1.2 Gbps to 5 Gbps exist, but coverage may be limited, and the plans we’ve seen above 2 Gbps are expensive).

Gigabit and multi-gig fiber-internet plans are growing more popular. Fiber is generally faster than cable, especially in upload speeds, but it brings added costs for companies because the technology requires new cables and network architecture. Providers like AT&T Fiber, CenturyLink, Frontier, Google Fiber, Optimum, Verizon, and Windstream, are expanding their networks. Don’t buy a cable modem if you subscribe to a fiber-internet plan such as Verizon Fios; such plans use their own equipment, to which you may be able to connect your own wireless router.

People who are looking to cut wires out of the equation entirely are starting to get excited about 5G wireless internet to the home and for mobile use. Though 5G uses fiber as its backbone, it employs wireless technology to deliver the service to homes and businesses. As we state in our router guide, 5G is cellular technology, faster than 4G LTE. Similar to the 5G cellular used in current smartphones, 5G home internet service is available from ISPs such as T-Mobile and Verizon; 5G home internet can bridge that “last-mile” connection between the ISP and your home, potentially replacing the coaxial (cable TV) or fiber connection drilled into the side of your apartment building or house. You don’t need a cable modem for 5G home internet, since the ISP provides a combination modem-and-router gateway device for its 5G home service.

This article was edited by Signe Brewster and Arthur Gies.