Motorola MB7621 Cable Modem | Pairs with Any WiFi Router | Approved by Comcast Xfinity, Cox, and Spectrum | for Cable Plans Up to 900 Mbps | DOCSIS 3.0
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Availability:
Only 1 left in stock, order soon!
Arrives
Sunday, Jul 12
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Size: DOCSIS 3.0 (1 Gbps Ethernet Port)
Features
- Model MB7621 is recommended for actual cable Internet service speeds up to 900 Mbps. Wirecutter rates this the best modem for most people. A Full-Band Capture Digital Tuner ensures faster, more reliable Internet.
- Pairs with any WiFi router - Seamlessly compatible with any WiFi router to connect all your devices. This cable modem does NOT have a built-in wireless router or telephone call capability.
- Cost-saving solution: Owning your own modem typically saves the average home $156 per year in monthly rental charges. (Savings are shown for Comcast Xfinity and vary by cable service provider.)
Brand: Motorola
Internet service provider: BrightHouse, Charter Spectrum, Comcast Xfinity, Cox, Time Warner Cable
Connectivity Technology: Ethernet
Compatible Devices: Personal Computer
Product Dimensions: 7.25"L x 2.25"W x 7.88"H
Connectivity Technology: Ethernet
Compatible Devices: Personal Computer
Number of Ports: 1
Maximum Downstream Data Transfer Rate: 1000 Megabits Per Second
Maximum Upstream Data Transfer Rate: 246 Megabits Per Second
Data Transfer Rate: 1000 Megabits Per Second
Number of Ethernet Ports: 1
Item Dimensions L x W x H: 7.25"L x 2.25"W x 7.88"H
Color: Black
Brand: Motorola
Internet Service Provider: BrightHouse, Charter Spectrum, Comcast Xfinity, Cox, Time Warner Cable
Modem Type: Cellular modem
UPC: 855631006347
Manufacturer: MTRLC LLC
Mfr Part Number: MB7621-10
Model Number: MB7621
Unit Count: 1.0 Count
Item Weight: 0.07 Pounds
Warranty Description: 2 YEAR MANUFACTURER
Built-In Media: MODEM
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Sunday, Jul 12
Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Similar Products
Top Amazon Reviews
Size: DOCSIS 3.0 (1 Gbps Ethernet Port)
Use-Case/Set-up: - Provider: Xfinity/Comcast - Wireless Router: Netgear Nighthawk X6S - Modem: Motorola Model MB7621 (24x8) - Company that designed the Modem's chip: Broadcom ---- - It is true that there are other modems that are cheaper. As someone that has worked in the semi-conductor industry, the (a) quality of the silicone-chip/processor and (b) quality of the materials that are used--are the two main inputs that separates the quality of various modems. This line of Motorola modems are made with chips designed and produced by Broadcom. The quality of the design and integration is more expensive, and (for me) it is worth the slight extra cost. This line of Motorola modems with Broadcom chips are workhorses--quality designs with good build/parts quality that are reliable and endure. - Tip: from a hardware and longevity perspective, it is better to have two devices: a separate modem and a separate wireless router. There are two reasons for this. (1) The lifespan of chips is based primarily based on heat dissipation and usage. (Let your modems and wireless devices 'breathe' as this will increase the 'lifespan'--don't keep them in closed cabinets.). By combining a modem and router into one device, the device has to work that much harder and it will 'run' hotter (thereby decreasing the 'lifespan'). (2) If you purchase a combined modem and router device, and either the modem or router fails (expect about 4-6 years lifespan) then you have to buy a whole new unit each time either the modem or router fails. Usually, either the modem or router will fail before the other--both do not usually fail at the same time. ---- Thus far, this modem has proved to be a very reliable. This modem is currently (as of the writing of this review review), on Xfinity's/Comcast's official 'Supported Hardware' list. ---- Overview: - I have not seen any data through-put slow-down or video/audio lag--even during what are typically 'peak use' times of the day. - Data pull-down (downstream) speed remains consistently high. - Set-up was simple, quick, and easy. - The modem functions very well in conjunction with a Wireless Router made by a different company. - Data transfer speeds between the modem and the wireless router are also consistently high. - The silicon chip used in this generation of Motorola's Cable Modem is well-designed and manufactured; and while it is more expensive, thus far it has been worth it. - Due to the heat output, this modem does need to be kept in a well-ventilated area. Using this modem in a closed-off environment would definitely cause: a decrease in lifespan, a performance degradation, or both. - Overall: Great modem; highly recommended.
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Reviewed in the United States on October 29, 2018 by t-writer
Size: DOCSIS 3.0 (1 Gbps Ethernet Port)
I have xfinity performance pro which is rated for 150 mb/s down and 5 mb/s up. I've been using the Arris SB6141 modem which is 8 channel down x 4 channel up, great modem, no issues but it's speed maxed out at 120 mb/s down and 5 mb/s up. I figured what the heck might as well get the speed i'm paying for, so I purchased the Motorola SB7621 which is 24 channel down x 8 channel up. Internet speed is now 180mb/s down and 6mb/s up with a ping of 19ms. I am happy that I am now getting the speed I am paying for. Yes the upload speed didn't change much but that is because xfinity does not support 8 channel up in my area. This means even though this modem supports 8 channel up it only shows 4 active up channels when you log into it, this is not the modems fault, this is xfinity's doing. The download channels are fine, all 24 channels show up and are active. Yes, I could have purchased a 16 channel down and 4 channel up modem and received the same current speeds but at the time of purchase this modem was less than or the same amount as all the 16 x 4 modems. By buying this Motorola I can upgrade my internet speed down the road and still be covered. Another good thing is that this modem has the Broadcom chipset not the Intel puma. The modem comes with good instructions and is well packaged. Setup was a breeze. I didn't have to call xfinity. All I did after I hooked up just the modem to my PC was navigate to motorola.com which brought up the xfinity activation page. Then just log in with your xfinity credentials and follow the prompts. Very easy and welcomed as I didn't want to sit on the phone talking to xfinity support. I never do reviews but I figured this little box deserved one and hopefully this helps someone.
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Reviewed in the United States on March 14, 2018 by PG
Size: DOCSIS 3.0 (1 Gbps Ethernet Port)
Great product; easy to set up ; functioning fine.
Reviewed in the United States on April 5, 2026 by Larry Ray Charles
Size: DOCSIS 3.0 (1 Gbps Ethernet Port)
So, I have some screenshots below on my tests with the modem. They stay fairly consistent. I upgraded recently to 500mbps plan on WOW! and they came over, installed a new modem. Well the new modem was complete garbage. It would reboot 1 to 3 times a day and the speed was all over the place. Occasionally would get 400mbps or 30 mbps. It was no telling. Enter the motorola MB7621, which I had another modem that was just as good, but couldn't "deal with" the speeds. So this modem seems to do the trick. Although I am not getting 500mbps, i am get a consistent 250mbps from Time Warner and Spectrum nodes. The Bresco node was even more surprising! I was getting around 40 to 60mbps with Bresco but now I am getting 100mbps. Very happy. Long as the darn modem doesn't reboot every day, i think it will be a win. My wife needs a stable connection on Wednesdays because she works from home. I need a stable connection because occasionally I work from home as well. I also felt that I would never get 500mbps but I don't see how anyone could exceed that speed unless if they were streaming 5 4k movies. 250Mbps is good enough for my family. I hope this is useful someone else. I will try to remember to post an update 6 months later.
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Reviewed in the United States on January 27, 2020 Reviewed in the United States on January 27, 2020 by Tbay007
Size: DOCSIS 3.0 (1 Gbps Ethernet Port)
I purchased this Motorola model MB7621 to replace an ancient and slow Motorola SURFboard SB5120 modem that I had been using for the past decade or more. Keeping up with the times does make a difference and I've had no problems with this to date after several months of reliable use. Size: I was a bit surprised of the size of this unit when it arrived. My old SURFboard SB5120 modem was about 3/4 of this size and figured this would be roughly the same. To my amazement, this thing stands 8" tall, vs. the 5 or 6 inches that the old SURFboard modem was. I figure everything gets smaller as technology improves, but not in this case. Nevertheless, that's nothing for me to take stars off for and the dimensions are likely in the description anyway. No real biggie. Hookup: The hookup was as simple as hooking up the AC adapter, coax cable and ethernet cable. That part took about 15 seconds in total to do. The time consuming part for me was spending the next hour on the phone (texting) with my cable service provider, between being put on hold and for them to swap out the modem in their system from my old one to the new one. And as luck would have it, the service provider asked me to provide a MAC # that was on my new router to them. I told them that the label has a "CM MAC" number and I asked them if that was what they were looking for. They said "no", it was some other number that was either on a label on the router, on the box or somewhere in the manual. After a wild goose chase of scouting around for some mysterious "MAC" number, I was unable to find any others they were looking for. I snapped a photo of the label on the bottom of my new router and sent that to them for reference. I was put on hold for a few minutes. They come back on, only to then apologize and to tell me that the router label's "MC MAC" number was in fact the same as a "MAC" number that they were asking for to begin with. Sigh... Hopefully this might help anyone else who is getting that runaround. Anyway, after the hour long fiasco, it was activated by my cable service provider and was then up and running smoothly and ever since. No issues so far and it's fast, reliable and smooth. When you have ancient equipment, you don't really know what you're missing out on until you upgrade and modernize. I'd recommend this router to anyone whose looking for an upgrade. I'll keep things updated, in the event that anything ever changes in it's performance or otherwise.
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Reviewed in the United States on June 2, 2020 by Bostonfan
Size: DOCSIS 3.0 (1 Gbps Ethernet Port)
I have spectrum 200Mbps plan and wanted something for future upgrade to their 400 plan. They have free modem to use, but after several years of thinking bad lag was an online gaming issue and multiple netgear routers with QoS setup to try to compensate, I decided to search the provided arris modem and found the Intel puma 6 issues and they were exactly what I have dealt with over last couple years while online gaming. Especially if wife and I partied up in cod or bf, it would take 10-20 bullets for a kill when playing on old modem. So pulled plug and after verifying supported modem for their 400Mbps plan, and the great price for the Broadcom chip. Received it in 2 days and easily installed the modem and powered up. Then came the worst part, it would not activate online and had to call spectrum. I have internet only plan but have used their triple play in past during promo price. So first guy gets the mac address and all is going great until he comes back from hold and says the modem does not meet the speed requirements. Upon disagreements with him and explaining it was on the list of supported modems, he transfers me to internet support and have to start over with new agent. So she comes back with the same error on their system and I explain about it being on the support list. Give the model number and she confirms it is suppose to work. I even agree to go ahead and upgrade to higher speed plan for the 400 since it was on that list. She suggests it would not be causing that issue. Ten minutes later, she asks me to power down and back on. Then received email popups from mail client on pc. Open browser and it loads to the activation page and has it listed as the active modem. Not sure if their was an issue because had prior had telephone service and it was still a provision on the system or what, but she got it working properly. Now been using it for about 2 weeks and speed tests have the same speeds as what I had prior, but what a world of difference online fps gaming that I have now. The last 2-3 years thinking it was the game or coding when it was the Intel puma 6 chip in my old modem....
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Reviewed in the United States on January 19, 2020 by Michael
Size: DOCSIS 3.0 (1 Gbps Ethernet Port)
Motorola MB8611 Likes + Great price + Compatible/works well with Xfinity + 32 downstream channels make streaming content and online gaming a breeze + Future-ready with DOCSIS 3.1 + Small and lightweight + Well vented Dislikes - Might be overkill if you don't have a Gigabit plan CONCLUSION Upgrade I replaced my Arris SB8200 with the Motorola MB7621, and now the Motorola MB8611. It's a solid device that allows even faster internet on my devices with the same Xfinity plan. Initial issues I was experiencing drops every morning at the same time practically. I got errors like "No Ranging Response", "Started Unicast Maintenance Ranging - No Response received - T3 time-out", and "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing". Restarting and resetting didn't help, as the modem would come back on eventually on its own. Resolve My particular issue was likely due to the old coaxial cables from the early 1990s when the house was built. New lines and connectors were installed. I also removed the splitter from the outside box since I cut the cord. So, from experience, I can definitely attest to how capable this modem is and performs without issue on Xfinity. Praise Thanks to Comcast. I called and the tech came out just under 2 hours later. My security cameras and entertainment all depend on the internet, and I can honestly say I didn't miss out on much in that short time. ASSOCIATED DEVICES -Dell XPS 8900 -Netgear RAX120
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Reviewed in the United States on September 5, 2020 Reviewed in the United States on September 5, 2020 by Omar, The Original
Size: DOCSIS 3.0 (1 Gbps Ethernet Port)
I bought this modem for a vacation rental. The place originally had a modem/wifi router combo that had a lot of limitations, including the inability to change the SSID. So I decided to replace that modem with separate modem and wifi hardware. The local cable company requires a DOCSIS 3.0 modem so I bought this one, thinking it was a very good modem. I was quite wrong! For the entire ~8 months I used this modem, I experienced intermittent internet outages. I spent a lot of time and money upgrading a 250 foot run of coax cable, then the wifi router, and in the end figured out it was the modem itself. It will randomly go into one of two failure modes: In the rarer of the failure modes, you would ping its local 192.168.100.1 address and about 90% of the packets would drop but some would get responded to. In that mode, you could browse to 192.168.100.1 to bring up the modem's setup page, and from there see the signal levels. The page would load very slowly if at all, but if you could load the page, you could see that the modem signal levels all looked normal. And the front panel indicator lights would indicate the modem was connected and online. In the more common failure mode, it just wouldn't respond to pings at all. By this time I had upgraded my wifi stuff to enterprise-quality Ubiquiti gear, with a separate router/security gateway, wireless access point, and managed switch. Even if I ssh'd into the router (the thing connected directly to the modem), I couldn't even ping it from there. Meanwhile the modem's front panel indicator lights would still show it being online. In either of these modes, cycling the modem's power clears the condition and the modem starts working again... maybe for an hour, maybe for a week. Very strange. I ended up replacing the modem with an Arris Surfboard and have had zero problems ever since. The Arris is "only" a 16x4 modem and I'm getting 50% faster throughput than I was getting out of this 24x8 Motorola modem. Something else I learned: Motorola does not make modems anymore. They sold the Surfboard product line to Arris, and apparently everything still Motorola-branded is actually made by a company called Zoom (not to be confused with the video conferencing app of the same name). Their tech support is very slow to respond to inquiries. This modem turned out to be an expensive headache for me. Buy an Arris instead.
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Reviewed in the United States on August 7, 2020 Reviewed in the United States on August 7, 2020 by Dave C.