I grew up just north of Boulder, Colorado, so I’m biased, but I believe it to be one of the country's most unique, beautiful cities. Some might know it as the home of the Colorado Buffaloes college football team, but it can also brag about the speed of its internet connections relative to the rest of the state.
If you live in Boulder (or plan to move there), you have a handful of options, but the two most widely available internet service providers are Xfinity and CenturyLink. CNET’s pick for the best overall internet service provider in Boulder is Xfinity due to its extensive coverage across the city and wide selection of plans. Other options include CenturyLink, which is also widely available but offers only slower DSL plans, fiber plans from Quantum Fiber and 5G home internet offerings from T-Mobile (and, to a lesser degree, Verizon).
Our methodology
CNET considers speeds, pricing, customer service and overall value to recommend the best internet service in Boulder across several categories. Our evaluation includes referencing a proprietary database built over years of reviewing internet services. We validate that against provider information by spot-checking local addresses for service availability. We also do a close read of providers' terms and conditions and, when needed, will call ISPs to verify the details.
Despite our efforts to find the most recent and accurate information, our process has some limitations you should know about. Pricing and speed data are variable: certain addresses may qualify for different service tiers, and monthly costs may vary, even within a city. The best way to identify your particular options is to plug your address into a provider's website.
Also, the prices, speed and other information listed above and in the provider cards below may differ from what we found in our research. The cards display the full range of a provider's pricing and speed across the US, according to our database of plan information provided directly by ISPs. At the same time, the text is specific to what's available in Boulder. The prices referenced within this article's text come from our research and include applicable discounts for setting up automatic payments each month -- a standard industry offering. Other discounts and promotions might also be available for things like signing a term contract or bundling with multiple services.
To learn more about how we review internet providers, visit our full methodology page.
Best internet in Boulder in 2023
Boulder residents can expect median download speeds of approximately 236 megabits per second, according to Ookla Speedtest data -- considerably faster than Colorado's statewide median (180Mbps) and the national median (210Mbps). Not too shabby.
Best internet provider in Boulder, CO
Our take - Xfinity is a reliable cable internet provider offering fast download speeds and extensive service across most of the city. Its cable broadband generally scores above-average marks in customer satisfaction surveys, including the most recent American Customer Satisfaction Index report, and finished above average in three of four regions in the J.D. Power study for 2022. The one area where it didn’t? The East region, where Xfinity fell short of the average by one point but still placed second ahead of Cox, Frontier, Optimum and Spectrum.
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Or call to learn more: (877) 498-5506
Check with Xfinity
Connection
Cable
Speed range
75 - 2,000 Mbps
Price range
$20 - $120 per month
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Our take - Lumen Technologies is the parent company of CenturyLink and Quantum Fiber, two broadband services available in Boulder. CenturyLink offers DSL connections to more than three-quarters of households in the area. At the same time, Quantum Fiber is a 100% fiber-optic service that offers much faster (and symmetrical) download and upload speeds. As noted in our CNET ISP reviews, fiber internet trumps cable connections, which best DSL services.
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Or call to learn more: (877) 609-6623
Check with Quantum
Connection
Fiber
Speed range
200 - 8,000 Mbps
Price range
$30 - $165 per month
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Best fixed wireless internet in Boulder, CO
Our take - T-Mobile's cellular network won't deliver speeds that match Xfinity or Quantum Fiber, but it should be adequate for households with three or fewer people. It also received the highest approval rating of any non-fiber provider in the US, according to the 2023 American Customer Satisfaction Index survey.
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Or call to learn more: (877) 687-6988
Check with T-Mobile
Connection
Fixed wireless
Speed range
72 - 245 Mbps
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Source: CNET analysis of provider data.
Other available internet providers in Boulder
Though we think Xfinity, Quantum Fiber and T-Mobile are the best providers in the area, Boulder has other ISP options to consider.
Pricing info on Boulder home internet service
The average starting price for internet in Boulder is just under $42 per month -- less expensive than the national average but just a few dollars more per month than its bigger sibling to the south, Denver, which comes in at $39.
Cheap internet options in Boulder
The cheapest internet plan in Boulder is Xfinity’s Connect plan, which features max download speeds of 75Mbps for $20 per month. There are plenty of caveats, however: That promotional price lasts for only one year and doesn’t include an optional $15-per-month charge for equipment rental (which you can waive if you have your own modem and router).
T-Mobile Home Internet, which starts at $50 monthly, drops to $30 per month when you bundle an eligible cellphone plan, such as Go5G Plus and Magenta Max.
It's worth noting that you might get a discount on any of the plans. The federal government's Affordable Connectivity Program provides low-income households a $30 monthly discount on high-speed internet. Qualifying households will find that money fully covers some of the plans we list below.
Source: CNET analysis of provider data.
Boulder broadband speeds
Just about all Boulder households have access to broadband internet speeds of 250Mbps down and 25Mbps upload. As we mentioned earlier, Boulder residents see much higher median download speeds than the rest of the state.
Source: CNET analysis of provider data.
How CNET chose the best internet providers in Boulder
Internet service providers are numerous and regional. Unlike the latest smartphone, laptop, router or kitchen tool, it's impractical to personally test every ISP in a given city. So what's our approach? For starters, we tap into a proprietary database of pricing, availability and speed information that draws from our own historical ISP data, partner data and mapping information from the Federal Communications Commission at FCC.gov.
This guide leverages an in-house artificial intelligence tool called RAMP, which is trained on our own writing and uses our database to generate content about specific internet service providers that our writers can use in determining and presenting our picks for a given guide. Check CNET’s AI policy for more information about how our teams use (and don’t use) AI tools.
Because our database isn't exhaustive, we go to the FCC’s website to check the primary data for ourselves and make sure we’re considering every ISP that provides service in an area. Plans and prices also vary by location, so we input local addresses on provider websites to find the specific options available to residents. We look at sources, including the American Customer Satisfaction Index and J.D. Power, to evaluate how happy customers are with an ISP's service. ISP plans and prices are subject to frequent changes; all information provided is accurate as of our prepublication fact-check.
Once we have this localized information, we ask three main questions:
While the answer to those questions is often layered and complex, the providers who come closest to “yes” on all three are the ones we recommend. To explore our process in more depth, visit our how we test ISPs page.
What’s the bottom line on internet providers in Boulder?
Xfinity covers nearly every address in the city and features the widest array of plan choices of any provider in the area. That’s why it gets our nod for the best ISP in the city. However, Boulder households have other viable options, including fiber plans from Quantum Fiber and a fixed wireless connection from T-Mobile Home Internet.
Internet providers in Boulder: FAQs
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