In San Mateo County there are 6 residential Fiber providers covering 83.61% of the county. The average home can get speeds up to 5,340 Mbps. Note that we may have a financial relationship with some of the providers below. This does not influence rankings, and helps us provide high-quality detailed information for free.
This page contains all Fiber internet providers in San Mateo County, CA.
To see availability maps for all providers including fiber, cable, DSL, and more in San Mateo County, CA please click below.
San Mateo County, CA Availability Maps
Fiber Internet Service Providers in San Mateo County
Data updated 11/14/2025, based on FCC data from 12/31/2024. This is the most current data available as of .
To avoid wasting your time, providers with less than 1% coverage in San Mateo County are not shown.
San Mateo County Satellite TV & Internet Providers
DISH Satellite TV
DIRECTV Satellite TV
Not sure whether to choose Dish or DIRECTV? For most people most of the time we recommend DISH. But click here to learn more.
Viasat Satellite Internet
Where in San Mateo County is fiber internet available?
Fiber Internet Availability Key
Fiber is available in 83.61% of San Mateo County. Areas in green have fiber internet service, where areas in yellow or red may not. The most widely available provider is AT&T. Call one of the companies with service in San Mateo County above to see who has service at your home.
How fast is fiber internet in San Mateo County?
The map below shows maximum fiber internet speeds by area in San Mateo County.
Fiber Internet Speed Key
The average San Mateo County home can get up to 5,340 Mbps on their fiber internet plan. The fastest fiber download speed in the county is 25,000 Mbps, which less than 1% of residents can get. Some homes and apartments do not have access to these speeds. On the slower end, for example, 8.52% of homes can only purchase plans up to 1,000 Mbps. See the internet provider details below for info about their speed and coverage in San Mateo County.
Fiber internet speeds tend to be faster in the southeast parts of San Mateo County, and slower in the north areas of the county.
Is fiber the fastest internet I can get in San Mateo County?
The fastest internet for you may vary based on where in San Mateo County you live. In general, cable competes most often with fiber in the county.
- Fiber is the fastest internet type for 74.56% of San Mateo County homes.
- Cable is fastest for 24.83% of the county.
- DSL is fastest for less than 1%.
- Fixed wireless is fastest for less than 1%.
- Satellite internet may be the only option for less than 1% of San Mateo County homes.
Fiber Providers in Depth
Below you'll find which TV and internet providers offer service in San Mateo County, along with details on where in San Mateo County and at what speeds.
EarthLink Fiber in San Mateo County, CA
EarthLink fiber coverage
About 77.60%, or 593,225 people, have EarthLink fiber internet available to them in the county. The company covers the entire San Mateo County area. EarthLink is one of the largest internet service providers internet service providers in the US, with internet service available in much of San Mateo County.
EarthLink fiber download speeds
EarthLink is above average when comparing download speeds to all other internet providers in San Mateo County. Versus other fiber providers in the area, EarthLink fiber is below average. There are 2 different maximum speeds throughout San Mateo County. The fastest plan anyone in San Mateo County can order from EarthLink goes up to 5,000 Mbps, the slowest package only goes up to 1,000 Mbps, and the county-wide average maximum speed for San Mateo County customers is up to 4,688 Mbps.
Show all download speeds
- 92.2% up to 5,000.0 Mbps
- 7.8% up to 1,000.0 Mbps
EarthLink fiber upload speeds
In San Mateo County download speeds tend to be equal to than upload speeds for EarthLink fiber. Compared to other ISPs, EarthLink is above average where upload speeds are concerned, and below average compared to other San Mateo County fiber providers. EarthLink offers 2 different upload speeds across the county, so your internet plan's upload speed may vary by neighborhood . The fastest upload speed available to anyone from this ISP in San Mateo County is up to 5,000 Mbps. Some customers have slower plan choices, which only go up to 1,000 Mbps. On average, EarthLink customers can get speeds up to 4,688 Mbps.
Show all upload speeds
- 92.2% up to 5,000.0 Mbps
- 7.8% up to 1,000.0 Mbps
AT&T Fiber in San Mateo County, CA
AT&T fiber coverage
About 77.60%, or 593,225 people, have AT&T fiber internet available to them in the county. The company covers the entire San Mateo County area. AT&T is one of the largest internet service providers internet service providers in the US, with internet service available in much of San Mateo County.
AT&T fiber download speeds
AT&T is above average when comparing download speeds to all other internet providers in San Mateo County. Versus other fiber providers in the area, AT&T fiber is below average. There are 2 different maximum speeds throughout San Mateo County. The fastest plan anyone in San Mateo County can order from AT&T goes up to 5,000 Mbps, the slowest package only goes up to 1,000 Mbps, and the county-wide average maximum speed for San Mateo County customers is up to 4,688 Mbps.
Show all download speeds
- 92.2% up to 5,000.0 Mbps
- 7.8% up to 1,000.0 Mbps
AT&T fiber upload speeds
In San Mateo County download speeds tend to be equal to than upload speeds for AT&T fiber. Compared to other ISPs, AT&T is above average where upload speeds are concerned, and below average compared to other San Mateo County fiber providers. AT&T offers 2 different upload speeds across the county, so your internet plan's upload speed may vary by neighborhood . The fastest upload speed available to anyone from this ISP in San Mateo County is up to 5,000 Mbps. Some customers have slower plan choices, which only go up to 1,000 Mbps. On average, AT&T customers can get speeds up to 4,688 Mbps.
Show all upload speeds
- 92.2% up to 5,000.0 Mbps
- 7.8% up to 1,000.0 Mbps
Sonic Fiber in San Mateo County, CA
Sonic fiber coverage
About 27.55%, or 210,605 people, have Sonic fiber internet available to them in the county. The company covers the central, southeast, northwest, north, east, and south San Mateo County area. Sonic is a large internet service provider internet service providers in the US, with internet service available in a small portion of San Mateo County.
Sonic fiber download speeds
Sonic is above average when comparing download speeds to all other internet providers in San Mateo County. Versus other fiber providers in the area, Sonic fiber is below average. There are 2 different maximum speeds throughout San Mateo County. The fastest plan anyone in San Mateo County can order from Sonic goes up to 10,000 Mbps, the slowest package only goes up to 1,000 Mbps, and the county-wide average maximum speed for San Mateo County customers is up to 4,555 Mbps.
Show all download speeds
- 39.5% up to 10,000.0 Mbps
- 60.5% up to 1,000.0 Mbps
Sonic fiber upload speeds
In San Mateo County download speeds tend to be equal to than upload speeds for Sonic fiber. Compared to other ISPs, Sonic is above average where upload speeds are concerned, and below average compared to other San Mateo County fiber providers. Sonic offers 2 different upload speeds across the county, so your internet plan's upload speed may vary by neighborhood . The fastest upload speed available to anyone from this ISP in San Mateo County is up to 10,000 Mbps. Some customers have slower plan choices, which only go up to 1,000 Mbps. On average, Sonic customers can get speeds up to 4,555 Mbps.
Show all upload speeds
- 39.5% up to 10,000.0 Mbps
- 60.5% up to 1,000.0 Mbps
Atherton Fiber Fiber in San Mateo County, CA
Atherton Fiber fiber coverage
About 2.64%, or 20,198 people, have Atherton Fiber fiber internet available to them in the county. The company covers the southeast San Mateo County area. Atherton Fiber is an average-sized internet service provider internet service providers in the US, with internet service available in a very small piece of San Mateo County.
Atherton Fiber fiber download speeds
Atherton Fiber is above average when comparing download speeds to all other internet providers in San Mateo County. Versus other fiber providers in the area, Atherton Fiber fiber is above average. There are no different maximum speeds throughout San Mateo County. The fastest plan anyone in San Mateo County can order from Atherton Fiber goes up to 10,000 Mbps, and all San Mateo County customers can get this speed.
Show all download speeds
- 100.0% up to 10,000.0 Mbps
Atherton Fiber fiber upload speeds
In San Mateo County download speeds tend to be equal to than upload speeds for Atherton Fiber fiber. Compared to other ISPs, Atherton Fiber is above average where upload speeds are concerned, and above average compared to other San Mateo County fiber providers. Atherton Fiber offers no different upload speeds across the county. The fastest upload speed available to anyone from this ISP in San Mateo County is up to 10,000 Mbps, which is available to everyone covered.
Show all upload speeds
- 100.0% up to 10,000.0 Mbps
Astound Broadband Fiber in San Mateo County, CA
Astound Broadband fiber coverage
About 2.22%, or 16,941 people, have Astound Broadband fiber internet available to them in the county. The company covers the central, northwest, southeast, north, and east San Mateo County area. Astound Broadband is one of the largest internet service providers internet service providers in the US, with internet service available in a very small piece of San Mateo County.
Astound Broadband fiber download speeds
Astound Broadband is below average when comparing download speeds to all other internet providers in San Mateo County. Versus other fiber providers in the area, Astound Broadband fiber is below average. There are 2 different maximum speeds throughout San Mateo County. The fastest plan anyone in San Mateo County can order from Astound Broadband goes up to 5,000 Mbps, the slowest package only goes up to 1,500 Mbps, and the county-wide average maximum speed for San Mateo County customers is up to 1,594 Mbps.
Show all download speeds
- 2.7% up to 5,000.0 Mbps
- 97.3% up to 1,500.0 Mbps
Astound Broadband fiber upload speeds
In San Mateo County download speeds tend to be equal to than upload speeds for Astound Broadband fiber. Compared to other ISPs, Astound Broadband is below average where upload speeds are concerned, and below average compared to other San Mateo County fiber providers. Astound Broadband offers 2 different upload speeds across the county, so your internet plan's upload speed may vary by neighborhood . The fastest upload speed available to anyone from this ISP in San Mateo County is up to 5,000 Mbps. Some customers have slower plan choices, which only go up to 1,500 Mbps. On average, Astound Broadband customers can get speeds up to 1,594 Mbps.
Show all upload speeds
- 2.7% up to 5,000.0 Mbps
- 97.3% up to 1,500.0 Mbps
XFINITY from Comcast Fiber in San Mateo County, CA
XFINITY fiber coverage
About 2.00%, or 15,285 people, have XFINITY fiber internet available to them in the county. The company covers the northwest, central, east, southeast, and north San Mateo County area. XFINITY is one of the largest internet service providers internet service providers in the US, with internet service available in a very small piece of San Mateo County.
XFINITY from Comcast fiber download speeds
XFINITY is below average when comparing download speeds to all other internet providers in San Mateo County. Versus other fiber providers in the area, XFINITY fiber is below average. There are 3 different maximum speeds throughout San Mateo County. The fastest plan anyone in San Mateo County can order from XFINITY goes up to 2,000 Mbps, the slowest package only goes up to 1,000 Mbps, and the county-wide average maximum speed for San Mateo County customers is up to 1,764 Mbps.
Show all download speeds
- 70.7% up to 2,000.0 Mbps
- 28.4% up to 1,200.0 Mbps
- 0.8% up to 1,000.0 Mbps
XFINITY from Comcast fiber upload speeds
In San Mateo County download speeds tend to be faster than than upload speeds for XFINITY fiber. Compared to other ISPs, XFINITY is below average where upload speeds are concerned, and the slowest compared to other San Mateo County fiber providers. XFINITY offers 3 different upload speeds across the county, so your internet plan's upload speed may vary by neighborhood . The fastest upload speed available to anyone from this ISP in San Mateo County is up to 1,000 Mbps. Some customers have slower plan choices, which only go up to 35 Mbps. On average, XFINITY customers can get speeds up to 220 Mbps.
Show all upload speeds
- 3.9% up to 1,000.0 Mbps
- 68.5% up to 250.0 Mbps
- 27.6% up to 35.0 Mbps
San Mateo County Fiber by Area
This information is most helpful to those looking for homes or considering moving to San Mateo County or any of the areas nearby.
How does fiber internet in San Mateo County compare to the rest of California?
Fiber internet speeds in San Mateo County are much faster versus the average speeds in California: 0.00 Mbps in California versus 5,340 Mbps in the county. The state has similar fiber availability compared to the county. Average fiber coverage in California is 0.00% versus 83.61% in San Mateo County.
What zip codes have fiber internet?
Fiber internet coverage varies by zip code and neighborhood. Some examples in or around San Mateo County are shown below. You can enter any zip code here to see TV and internet providers by zip code.
What does fiber internet look like in other counties?
Below are counties nearby and with similar populations. This comparison can be useful if living somewhere with fast internet is important to you.
Nearby Counties
- Stanislaus County, CA: less fiber coverage, slower speeds
- Mariposa County, CA: less fiber coverage, slower speeds
- San Juan County, UT: less fiber coverage, slower speeds
- Rio Grande County, CO: less fiber coverage, slower speeds
- Alamosa County, CO: less fiber coverage, slower speeds
- Huerfano County, CO: less fiber coverage, slower speeds
- Stanton County, KS: less fiber coverage, slower speeds
- Grant County, KS: more fiber coverage, slower speeds
- Haskell County, KS: more fiber coverage, slower speeds
- Kiowa County, KS: less fiber coverage, slower speeds
Counties with Similar Populations
- Baltimore County, MD: more fiber coverage, slower speeds
- Cobb County, GA: less fiber coverage, slower speeds
- San Joaquin County, CA: less fiber coverage, slower speeds
- Middlesex County, NJ: less fiber coverage, faster speeds
- Monroe County, NY: less fiber coverage, faster speeds
- Montgomery County, PA: more fiber coverage, slower speeds
- Multnomah County, OR: more fiber coverage, slower speeds
- Norfolk County, MA: less fiber coverage, slower speeds
- Oklahoma County, OK: less fiber coverage, slower speeds
- Polk County, FL: less fiber coverage, faster speeds