7 Best Modems for Xfinity in 2026 (Including Mid-Split Picks)

The MB8611 has been the default recommendation for Xfinity for years, and the reason is that it does not have a weak point. DOCSIS 3.1 with a 2.5 Gbps Ethernet port means it can carry Xfinity’s Gigabit and Gigabit Extra tiers without the port becoming the bottleneck, a real problem with older modems that pair DOCSIS 3.1 to a single 1 Gbps port and then cannot deliver a 1.2 Gbps plan.

Active Queue Management is the underrated feature. AQM stops the modem’s own buffer from filling up when the connection is saturated, which is what causes ping to spike from 20 ms to 300 ms the moment someone starts a large download. On a household connection shared between gaming, video calls and streaming, it is more noticeable than any speed figure.

Motorola’s two-year warranty and US-based support are worth mentioning because cable modems fail in confusing ways, intermittent drops, slow degradation, and getting a straight answer from a human matters more here than with most hardware.

The limitation is that it is not mid-split. Upload speeds cap at whatever the standard upstream allocation gives you, typically around 35 Mbps on Xfinity. If that is fine for you, this is the modem. If it is not, skip to the CM2500.

The SB8200 is the modem that has been quietly working in millions of homes since 2018, and its age is mostly an advantage. Firmware is stable, Xfinity’s provisioning system knows it well, and activation almost never goes wrong, which is not something you can say about every newer modem.

Two 1 Gbps Ethernet ports rather than one 2.5 Gbps port is the key difference from the MB8611. In practice that caps you at gigabit. If your plan is 600 Mbps, 800 Mbps or a standard 1 Gbps tier, you will never notice; if you are on Gigabit Extra at 1.2 Gbps, you will lose speed you are paying for.

The 32 × 8 DOCSIS 3.0 channel bonding alongside its DOCSIS 3.1 OFDM channels matters more than it sounds. Not every part of Xfinity’s network runs DOCSIS 3.1 yet, and in those areas the modem falls back to 3.0, where having 32 downstream channels rather than 24 is the difference between a usable connection and a slow one at peak hours.

At $89 it is the cheapest way to stop paying rental fees, and it pays back in six months.

This is the modem to buy if uploads are the reason you are shopping. The CM3000 supports mid-split and high-split, which means on an upgraded Xfinity node it can pull the full upstream allocation rather than the narrow legacy slice. NETGEAR rates it at up to 2.5 Gbps down and 1 Gbps up, the upload figure is the one that makes it different from everything else here.

The port layout is the most complete in its class: one 2.5 Gbps Ethernet port for multi-gig plans, plus two 1 Gbps ports that support link aggregation for up to 2 Gbps wired to a compatible router. Most modems give you one port and leave it there.

DOCSIS 3.1 Active Queue Management and OFDMA are both present, so latency under load behaves well, relevant if the reason you want faster uploads is video calls rather than raw transfer speed.

The honest caveat is price. At $269 it costs eighteen months of Xfinity rental, and the mid-split capability is only useful if your neighbourhood has actually been upgraded. Confirm that before you buy, otherwise the CM3000 performs identically to a $130 modem.

The CM2500 is the CM3000’s cheaper sibling and, for most people, the more sensible one. It has the same mid/high-split capability, the feature you are actually paying for, at $72 less, and gives up only the extra Ethernet ports and a slice of headroom on download speed.

NETGEAR rates it at up to 2 Gbps down and 1 Gbps up. On Xfinity that translates to unlocking the 900 Mbps down / 100 Mbps up tier in upgraded areas, which is roughly a threefold improvement on upload compared with a standard DOCSIS 3.1 modem on the same line.

You get one 2.5 Gbps Ethernet port, which is the right amount for a modem, you connect exactly one router to it. The CM3000’s extra 1 Gbps ports and link aggregation are genuinely useful only in a specific setup most homes do not have.

The same warning applies: verify your area is mid-split before buying. Xfinity support can confirm it, and if your plan’s advertised upload speed has recently jumped, you are almost certainly upgraded.

Hitron is not a household name in the US, which is odd given that it supplies hardware to cable operators worldwide and has done for thirty years. The CODA56 is a straightforward, well-built DOCSIS 3.1 modem with a 2.5 Gbps Ethernet port and no unnecessary features.

Xfinity certifies it for plans up to 2 Gbps, and it is also certified with Spectrum and Cox, useful if there is any chance you will move or switch providers, because a modem tied to one operator becomes landfill when you change.

It runs noticeably cooler than the MB8611, which sounds trivial until you have had a modem in a media cabinet start dropping connection on hot afternoons. Heat is one of the most common causes of intermittent cable modem faults, and a cooler-running unit in a confined space is a genuine advantage.

The listing is aggressively worded about what the modem does not do, no WiFi, no voice, cable only, not fibre, which reads as defensive but reflects the reality that these are the most common returns. It is a modem. You need a router.

The B12 is Motorola’s replacement for the MB8611, same 32 × 8 channel bonding, same DOCSIS 3.1, same 2.5 Gbps Ethernet port, same Active Queue Management, in a smaller and better-ventilated case, for a dollar less.

On paper that makes it the obvious pick over the MB8611. In practice the older model still edges it for one reason: years of accumulated real-world use on Xfinity’s network, and a much larger body of troubleshooting knowledge if activation goes sideways. The B12 is newer and there is simply less of that.

The smaller footprint is a real benefit if space is tight. Cable modems tend to live behind televisions or inside cabinets, and the B12’s case is designed to shed heat in exactly those conditions, where the MB8611 has a mild reputation for running hot.

It carries the same approvals, Xfinity, Cox, Spectrum, RCN, Astound, and the same two-year warranty with US support. If price is equal and you value the smaller case, take it. If you would rather have the model with a decade of field history, take the MB8611.

If you want one box instead of two, the G34 combines a DOCSIS 3.1 modem with a dual-band WiFi 6 router rated AX3000. At $180 it replaces both an Xfinity gateway and a separate router purchase, and it is the closest equivalent to what Xfinity rents you, minus the $15 a month.

Plan support goes up to 2.5 Gbps on the cable side, with four gigabit Ethernet ports for wired devices. The WiFi 6 radio is competent for an apartment or a small house, roughly on par with a $90 standalone router, which is a fair trade inside a combo unit.

The structural downside of any modem-router combo applies here. When you want to upgrade your WiFi, you have to replace the modem too, even though the modem is fine. Cable standards change every five to seven years; WiFi standards change every three. Separates let you upgrade the half that is actually out of date.

There is also a troubleshooting cost: when something goes wrong, a combo unit makes it harder to tell whether the problem is your connection or your WiFi, because you cannot swap out one half to isolate it.