Yes, you can use your own modem with Xfinity, but it must be on their approved list
Xfinity allows you to bring your own modem instead of renting theirs, but the modem has to be one they have tested and certified. You cannot use any modem you want — it must appear on Xfinity's official approved modem list. If your modem is not on that list, Xfinity's network will not recognize it, and you will have no internet service.
The main reason to use your own modem is cost. Xfinity charges between $11 and $14 per month to rent a modem, depending on your region. Over two years, that adds up to $264 to $336 for equipment you do not own. A modem you buy costs $100 to $200 upfront but becomes yours permanently — you can take it with you if you move or switch providers.
Before you buy or plug in any modem, check whether it is actually on Xfinity's list. An approved modem is the only thing that will work.
Key Takeaways
- Your modem must be on Xfinity's official approved modem list, or it will not connect to their network at all.
- Xfinity rents modems for $11 to $14 per month, so buying your own saves money if you keep it for more than a year.
- You can find Xfinity's approved modem list on their website by searching for your internet speed tier.
- Once you own a modem, you can use it with any internet provider that supports that modem type, even if you leave Xfinity.
- Xfinity will not provide technical support for a modem you own, though most modems come with their own support line.
How to check if your modem is approved by Xfinity
Go to Xfinity's modem approval page and search for your modem's model number. The model number is usually on a sticker on the back or bottom of the modem. Type it into their search tool and it will tell you whether that exact model works with your internet speed.
Xfinity maintains separate lists for different internet speeds. A modem approved for 300 Mbps service might not be approved for their fastest 1200 Mbps tier. Check the list that matches the speed you are paying for, not just any list. If you upgrade your speed later, you may need to check again whether your modem still qualifies.
If you cannot find your modem on the list, do not buy it or plug it in. Contact Xfinity to ask whether they have tested that model. If they have not, you will need a different modem.
What modems Xfinity actually approves
Xfinity approves modems from brands like Netgear, Motorola, Arris, and Linksys. They do not approve every model those companies make — only specific ones that have passed their testing. Common approved models include the Netgear CM500, Motorola MB8600, and Arris SB8200, but the full list changes as manufacturers release new equipment.
Most approved modems cost between $100 and $200. The cheaper ones ($100 to $130) typically support speeds up to 300 or 400 Mbps. The more expensive ones ($150 to $200) support higher speeds like 600 Mbps or 1200 Mbps. If you have a basic internet plan, you do not need to pay for a modem that supports speeds you will never use.
Before you buy, confirm the modem is on the current Xfinity list. Older modems sometimes get removed as Xfinity upgrades their network, even if they worked in the past.
The cost difference between renting and buying
Xfinity's monthly modem rental fee is $11 to $14, depending on your region. Over 24 months, that is $264 to $336 in rental costs. A modem you buy for $150 costs less than 12 months of rent, so you break even in about a year. After that, you own the equipment and pay nothing more.
If you stay with Xfinity for two years or longer, buying almost always saves money. If you think you might move or switch providers within a year, the math is closer — but even then, you own the modem and can take it with you or sell it.
One exception: if Xfinity offers you a promotion that includes a free modem rental for several months, that changes the timeline. Calculate your actual costs based on what you will actually pay, not the list price.
How to set up your own modem with Xfinity
Once you have an approved modem, unbox it and connect it to the coaxial cable that comes from your wall (the same cable that was connected to the Xfinity modem). Plug in the power cable. Wait two to three minutes for the lights to stabilize.
Open a web browser and go to 192.168.0.1 or 192.168.100.1 — one of these is usually the modem's default address. You may see a setup wizard. If you do, follow the on-screen steps. If not, the modem may self-set up on Xfinity's network within a few minutes.
If the modem does not set up automatically, call Xfinity at 1-800-934-6489 and tell them you have a new modem. Have the modem's model number and serial number ready. They will add it to your account and it should set up within 15 minutes. Do not return the old Xfinity modem until the new one is working.
What Xfinity will and will not support
Xfinity will set up your modem on their network and troubleshoot connection problems on their end. They will not help you set up the modem itself, change its settings, or fix problems with the modem's software or hardware. That is your responsibility or the modem manufacturer's.
If you have internet problems, Xfinity will first check whether the issue is on their network or your modem. If it is your modem, they will tell you to contact the manufacturer's support line. Most modem makers offer phone support and online chat, though response times vary.
This is a real difference from renting: Xfinity handles everything for a rental modem, but you handle the modem itself if you own it. For most people this is fine, but if you want zero responsibility for equipment troubleshooting, renting may be simpler.
What happens to your modem if you leave Xfinity
Your modem is yours to keep. You can take it with you if you move or switch to a different internet provider. Many other cable providers use the same modem types, so your modem may work with them too — but check their approved list first, because not all providers approve all modems.
If you move to a fiber or DSL provider, your cable modem will not work at all, because those services use different technology. In that case, you would need to buy a new modem for the new service. But if you switch to another cable provider in the same area, your modem often transfers over.
This is one of the biggest advantages of owning: you are not locked into Xfinity's equipment. If you decide to leave, you take the modem with you.
Frequently Asked Questions
Can I use a modem I already own from a previous internet provider?
Only if it is on Xfinity's approved list. Check the model number against their list before you plug it in. Many older modems are not approved for current Xfinity speeds, even if they worked with another provider. If it is not on the list, Xfinity will not set up it.
What if I buy a modem and Xfinity later removes it from their approved list?
This is rare but can happen when Xfinity upgrades their network. If your modem is removed, you would need to buy a new one to stay with Xfinity. This is another reason to check the current list before buying, not an old list from a website or forum.
Do I have to return my modem when I cancel Xfinity service?
No. If you own the modem, it is yours. You only have to return equipment that Xfinity rented to you. Keep your receipt or proof of purchase in case there is ever a question about ownership.
Will my own modem give me faster internet than Xfinity's rental modem?
No. Your internet speed is determined by your plan and Xfinity's network, not the modem. Any modem on their approved list will deliver the same speed. A more expensive modem just supports higher speeds if you upgrade your plan later.
Can I use a modem that is not on Xfinity's list if I am willing to troubleshoot it myself?
No. Xfinity's network will not recognize an unapproved modem, so it will not connect at all. It is not a support issue — the modem straightforward will not work. You must use one from their approved list.