







The S33 combines DOCSIS 3.1 technology with a 2.5 Gigabit Ethernet port to unlock multi‑Gig internet plans and ultra‑responsive streaming and gaming. Buy it once and stop paying monthly rental fees!
Multi‑Gig speed for today & tomorrow: DOCSIS 3.1 performance supports cable internet plans up to 2.5 Gbps, delivering ultra‑fast streaming, gaming, and downloads.
Save on rental fees: Own your modem and avoid monthly equipment charges – check with your cable provider for plan compatibility.
Compact, modern design: Space‑saving footprint with simple LED indicators for power, upstream/downstream, and online status.
Easy setup: Connect cable, power on, and activate with your cable provider. Then connect a Wi‑Fi router to the Ethernet port for home Wi-Fi coverage.
Modem only: This cable modem requires a separate Wi-Fi router or mesh system for home Wi-Fi network.
Fast Ethernet: Provides a 2.5 Gigabit Ethernet port to support connecting high speed Wi-Fi routers. Plus, a 1 Gigabit Ethernet port lets you connect an additional wired device or backup handoff (service provider configuration dependent).
Provider compatibility: All SURFboard modems are CableLabs certified to work across major US Internet Service Providers. Tested and qualified for use with Cox, Xfinity, and Spectrum. Check with your provider to confirm device model support
Not compatible with fiber, DSL, or satellite services.
4 reviews for ARRIS SURFboard S33 DOCSIS 3.1 Multi‑Gig Cable Modem | 2.5Gbps + 1Gbps Ethernet Ports | Works with Xfinity, Cox, Spectrum | For Cable Internet Plans up to 2.5Gbps | Modem Only, Router Required
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$28.99

RC –
S33 Modem is great. Xfinity install… BIG pain
The ARRIS S33 modem was a great upgrade. My prior modem was another ARRIS product and it worked really well. I’ve had several ARRIS products and all have functioned without issue. The only reason I upgraded was because my old modem was running DOCSIS 3.0 and I wanted to move to DOCSIS 3.1 to get the most out of the 1.2Gps service that I’m paying for. This new S33 modem improved my speeds across all devices by well over 100Mbps. On my M1 iMac I’m now getting 950 Mbps on average. The ARRIS S33 modem is a five star product.I’ll summarize the rest of the story so you don’t have to read it if you don’t want to. You CAN use this modem with your Xfinity service. But you’re going to have to work to get it done. The saga below is provided so if you decide to activate this with Xfinity, you’ll have an idea of what you’ll go through.Now for the ugly: installing this modem with Xfinity service… This is a simple modem. It’s designed to be pretty much plug-n-play. Connect coax, plug in power, plug in ethernet cable then activate through Xfinity’s app. All the connections on the modem are simple. I went to Xfinity’s app to activate and the activation function wouldn’t work. It said I had to contact an Xfinity agent directly. So I started the chat with an Xfinity agent. I spent over an hour chatting with the agent as they tried to figure it out. First they said the modem isn’t compatible with Xfinity’s service. I pointed out it’s the recommended modem on Xfinity’s website. Then they said they couldn’t find the modem in their system so couldn’t register it on my account. More haggling. They escalated the issue. Escalation agent had the same problems. After more than an hour they told me I’d have to take the modem to a service center because “the service centers have special tools to scan the modem into the system directly.” He assured me no appointment was necessary with my case number. Off to the Xfinity service center I go. I get there and it’s a 45 minute wait. The guy says their case number doesn’t mean anything to them and I’d still have to wait in line. The guy calls my name and I walk up to the counter. As soon as I lay the modem box on the counter the guy says, “Oh, no. Another one of these.” He proceeds to tell me he’ll do everything he can to help but they’ve not been able to do anything with these modems in the service center. He says the service centers don’t have any special tools and have to do the same things the online agents do. And he comments that he wishes the online agents wouldn’t tell customers what the service centers can do, they’re always wrong and just dump problems on the service center. Sure enough, the modem isn’t listed in his system either. Nice guy and admits this situation has been causing a terrible customer experience with several customers. He escalates the case to some tech group offsite. He gives me a new case number and says they will have to try to manually configure the modem for my account and I should get a call within an hour. I walked out ticked off and skeptical that I’d get a call or that they’d fix it. 50 minutes later I get a call. A nice guy from the Xfinity tech group tells me he’s got it configured and it should install fine. Just have to activate it through the app. I reinstall the modem and go to the Xfinity app to activate. Same error in the app as before and it makes me contact an agent. So I start the chat and explain the situation. The chat agent says to give him a few minutes to review and attempt the activation. He comes back on about 5 minutes later and says it’s activated. Sure enough. The modem light is blue and I once again have data flowing. It took somewhere about 4 hours, two chat sessions, a trip to the local service center and referral to some higher Xfinity tech group; but it finally got installed.
Dave Wright –
Round Two for the ARRIS S33: Lightning Struck My First One, But I’m Still Hooked
This is my second time buying the ARRIS S33 DOCSIS 3.1 multi-gigabit cable modem—because lightning apparently decided my internet setup was too good and struck down my first one like Zeus himself was having a bad day. RIP, my beloved modem, you lasted just long enough to show me what true speed feels like before being vaporized in a flash.But honestly? I’m not mad. The ARRIS S33 is a beast. It supports DOCSIS 3.1, meaning it’s ready for the next-generation high-speed cable internet—like, up to 2 Gbps downstream and 1 Gbps upstream (if your ISP and plan are playing along). It’s also backwards compatible with DOCSIS 3.0, so if your ISP hasn’t fully upgraded yet, no worries.Installation is impressively painless. Plug and play, with support for IPv4 and IPv6, and it handles channel bonding like a champ—aggregating multiple channels to maximize throughput and minimize lag. I’ve thrown all kinds of traffic at it: 4K Netflix, intense online gaming sessions, video calls where my face looks mostly presentable, and it doesn’t even break a sweat.The only caveat: lightning doesn’t play nice with electronics. So if you live somewhere prone to storms like me, consider a surge protector or UPS, unless you want to keep buying backup modems like this is a weird hobby.Bottom line: the ARRIS S33 is fast, reliable, and future-proof enough to handle whatever Comcast Xfinity throws at it. Just pray to the weather gods to keep your modem alive.
Bill H –
Works Perfectly.
Works perfectly. Of course, Comcast would like us to lease a less effective piece of junk from them for $15/mo when this device only costs $200 (I could have purchased a much cheaper model).
Gardener –
Bought New after 5 wks received open package. Returned n bought used unit. 1 1/2 year its fine
10-22-25 Update.So far the modem is working fine. I have not noticed any issues. I did some speed tests are it is about the same as the day I installed it. So far so good. ** Sorry about the 1 star rating but that was because the shipping was so slow and received an open box after all that waiting.5-17-24 Update.I wanted to try to get a replacement unit hoping it was new but Amazon system would not allow me to replace it with same unit but another merchandise only. So, I asked for refund into my CC and tried to buy another new one. A used unit popped up so I ended up buying it for about $100 less than new (which was in my opinion same as what I originally received.)Used unit (described as acceptable condition) arrived fast and it was in great condition, no visible scratches nor damage. I had to spend about 25mins on the phone with Cox Tech (took longer than it should have because numbers and alphabets are hard to get it right) and it was activated. After that, it was just a matter of turning off the router and restarting it. So overall installation was relatively painless. The download speed almost doubled and upload speed tripled compared to old modem so happy with this unit for now. I am equally concerned about longevity. I am not sure how long this will last but my last Arris Surfboard which this replaced did not break but was due to outdated speed. I will update this review as needed.Original Review – 5-12-24 I bought a S33 on April 9th with expected delivery in 10 days which was long but ok. There were two delays in shipping and finally received it on May 12th. When I opened the outer shipping bag, the box was open (tape seal was already cut) and all the plastic bag was cut open. Clearly not new and who knows what condition?????. I could have bought a refurb unit for $60 less and I received a questionable “New” item.I had not tested the unit since I was upset and returned it ASAP.I had kept dubious items in the past and at the end decided to send back but it was a day over so I had to eat it. so I immediately returned this item.