Motorola B12 DOCSIS 3.1 Multi-Gig Cable Modem (2.5G Port)

The Motorola B12 is a DOCSIS 3.1 cable modem with a 2.5 Gbps Ethernet port, built for gigabit and multi-gig cable plans. It is Motorola's successor to the popular MB8611, with the same core capabilities in a much smaller tower that fits on any shelf. Pair it with the router or mesh system of your choice and stop paying a monthly modem rental fee.

Motorola B12 at a Glance

• DOCSIS 3.1 with 32x8 DOCSIS 3.0 fallback, so it works on today's cable networks and the upgrades still rolling out.
• One 2.5 Gbps Ethernet port, which removes the roughly 940 Mbps ceiling that a standard Gigabit port puts on fast plans.
• Approved for Comcast Xfinity, Cox, Spectrum, RCN, and Astound residential internet.
• Active Queue Management (AQM) keeps lag down when the whole house is online at once.
• Modem only. There is no built-in WiFi and no phone jack.

Multi-Gig Speed Through a 2.5 Gbps Port

Gigabit cable plans are usually delivered a little faster than advertised, and a modem with a regular Gigabit port tops out around 940 Mbps no matter what the plan provides. The B12's 2.5 Gbps port lets that extra speed through. Motorola rates the modem for downloads just under 2,500 Mbps and uploads up to 800 Mbps where the provider's network and your plan support it.

To see those speeds on your devices, connect the B12 to a router with a 2.5 Gbps WAN port. With a standard Gigabit router it still works perfectly, and you keep the headroom for a later upgrade. Browse our wireless routers and mesh network systems for a match.

Lower Lag for Gaming, Calls, and Streaming

Active Queue Management controls how data lines up inside the modem when the connection is busy. Instead of letting one big download or 4K stream hold everything else up, AQM keeps the queue short so game traffic and video calls get through on time. Homes with many devices online at once notice it most.

Provider Compatibility

The B12 is approved for Comcast Xfinity, Cox, Spectrum, RCN, and Astound. It is a residential cable modem, so it does not work with fiber, DSL, or satellite service, and it does not carry cable phone service.

• Xfinity: on Xfinity's compatible device list at up to 2.32 Gbps download. It is not on Xfinity's separate Next Gen Speed Tier list, so plans that advertise uploads in the hundreds of megabits will run at standard upload speeds on this modem. See our Xfinity approved modems guide for the models that qualify.
• Cox: approved for Cox gigabit service.
• Spectrum: approved for Spectrum Internet plans through Gig. Spectrum's 2 Gig plan requires Spectrum's own equipment.

Provider lists change, so confirm your plan and region on your ISP's approved modem list before ordering.

Motorola B12 vs MB8611

The B12 replaces the MB8611 in Motorola's lineup. Performance is the same on paper. The difference is the size and the newer internals.

If you already own an MB8611 that works well, there is no speed reason to swap. If you are choosing between the two today, the B12 is the current model and takes up far less room.

What You Save by Owning

Most cable providers charge around $14 a month or more to rent a modem. Owning the B12 removes that charge, which adds up to as much as $168 per year. The modem typically pays for itself within the first year, and everything after that is savings.

Specifications

Frequently Asked Questions

Does the Motorola B12 have built-in WiFi?

No. The B12 is a standalone cable modem. Connect it to a separate WiFi router or mesh system to get wireless coverage in your home.

Is the Motorola B12 approved for Xfinity?

Yes. It is on Xfinity's compatible device list at up to 2.32 Gbps download. It is not on the Next Gen Speed Tier list, so it delivers standard upload speeds on Xfinity.

What is the difference between the Motorola B12 and the MB8611?

The B12 is the direct replacement for the MB8611. Both are DOCSIS 3.1 modems with 32x8 fallback and one 2.5 Gbps Ethernet port. The B12 has updated internals and a far more compact tower design.

Do I need a 2.5 Gbps router to use the B12?

No. Any router with an Ethernet WAN port works. A router with a 2.5 Gbps WAN port is only needed if your plan is faster than about 940 Mbps and you want the full speed.

Does the Motorola B12 work with fiber or DSL internet?

No. It is a cable modem for DOCSIS cable internet providers only. It does not work with fiber, DSL, or satellite service.

Does the Motorola B12 support cable phone service?

No. The B12 has no telephone jack. If you have voice service through your cable provider, you need a modem with built-in telephony.

How do I set up the Motorola B12?

Connect the coax cable, plug in power, and run an Ethernet cable from the modem to your router. Then activate it through your provider's app or activation page, or by calling them with the modem's MAC address from the label on the bottom.