San Mateo County, CA Cell Phone Coverage Map & Network Rankings (2026)

Find the best cell phone network and plan to use in San Mateo County, CA

Coverage rankings for San Mateo County, CA

Verizon currently ranks first for coverage in this area, with a coverage score of 69.0. Compare Wireless Carriers uses FCC broadband map data to estimate and calculate coverage scores. More on that further below.

RankCarrierScoreOverall4G LTE5GFast 5GAverage Signal
1Verizon69.080.6%80.4%47.3%37.0% -93 dBm
2T-Mobile63.258.1%56.9%53.9%44.0% -86 dBm
3AT&T60.671.5%71.3%52.1%32.4% -107 dBm

Scores include coverage area, network type, and average signal strength.

Cell phone coverage map for San Mateo County, CA

Zoom in for local detail. Tap or click a colored area to see coverage and signal details. On mobile, use two fingers to move the map.

Coverage Key
Less covered More covered
Darker areas mean the carrier covers more of that location.

Map data © OpenStreetMap contributors, © CARTO. Rendered with MapLibre. FCC BDC mobile coverage processed by Compare Wireless Carriers.

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Cell phone coverage by network in San Mateo County, CA

#1

Verizon

Coverage Score 69.0
In San Mateo County, CA
Overall
80.6%
4G LTE
80.4%
5G
47.3%
Fast 5G
37.0%
Average Signal -93 dBm
#2

T-Mobile

Coverage Score 63.2
In San Mateo County, CA
Overall
58.1%
4G LTE
56.9%
5G
53.9%
Fast 5G
44.0%
Average Signal -86 dBm
#3

AT&T

Coverage Score 60.6
In San Mateo County, CA
Overall
71.5%
4G LTE
71.3%
5G
52.1%
Fast 5G
32.4%
Average Signal -107 dBm
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Coverage by city in San Mateo County, CA

Cities and towns are shown for county-level comparison. Coverage percentages use land-area only coverage.

CityVerizonAT&TT-Mobile
Atherton, CA 100.0% 100.0% 81.0% 48.3% -92 dBm 100.0% 100.0% 100.0% 75.0% -102 dBm 100.0% 100.0% 94.0% 61.2% -91 dBm
Baywood Park, CA 100.0% 100.0% 75.0% 58.3% -88 dBm 100.0% 100.0% 100.0% 83.3% -105 dBm 100.0% 100.0% 100.0% 100.0% -82 dBm
Belmont, CA 100.0% 100.0% 79.1% 60.9% -92 dBm 100.0% 100.0% 99.1% 60.9% -104 dBm 100.0% 100.0% 98.2% 95.5% -81 dBm
Brisbane, CA 100.0% 100.0% 97.1% 82.4% -86 dBm 100.0% 100.0% 100.0% 66.2% -101 dBm 100.0% 100.0% 100.0% 100.0% -73 dBm
Broadmoor, CA 100.0% 100.0% 100.0% 100.0% -79 dBm 100.0% 100.0% 100.0% 58.3% -95 dBm 100.0% 100.0% 100.0% 100.0% -72 dBm
Burlingame, CA 100.0% 100.0% 92.2% 79.6% -86 dBm 100.0% 100.0% 99.0% 71.8% -95 dBm 100.0% 100.0% 99.0% 92.2% -84 dBm
Colma, CA 100.0% 100.0% 100.0% 100.0% -82 dBm 100.0% 100.0% 97.8% 62.2% -98 dBm 100.0% 100.0% 97.8% 91.1% -84 dBm
Daly City, CA 100.0% 100.0% 97.8% 94.4% -82 dBm 100.0% 100.0% 98.9% 68.5% -97 dBm 100.0% 100.0% 97.2% 93.3% -76 dBm
East Palo Alto, CA 100.0% 100.0% 100.0% 100.0% -80 dBm 98.3% 98.3% 98.3% 79.7% -99 dBm 98.3% 98.3% 98.3% 96.6% -80 dBm
El Granada, CA 83.6% 81.9% 51.7% 16.4% -100 dBm 72.4% 72.4% 44.8% 23.3% -115 dBm 67.2% 67.2% 50.0% 34.5% -90 dBm
Emerald Lake Hills, CA 100.0% 100.0% 80.8% 50.0% -94 dBm 80.8% 76.9% 61.5% 3.8% -109 dBm 100.0% 100.0% 100.0% 96.2% -84 dBm
Foster City, CA 100.0% 100.0% 100.0% 96.7% -83 dBm 100.0% 100.0% 100.0% 73.3% -94 dBm 100.0% 100.0% 100.0% 100.0% -75 dBm
Half Moon Bay, CA 95.3% 95.3% 82.4% 67.6% -89 dBm 91.9% 91.9% 89.2% 68.2% -109 dBm 93.9% 93.9% 90.5% 84.5% -85 dBm
Highlands, CA 100.0% 100.0% 87.1% 71.0% -88 dBm 100.0% 100.0% 100.0% 96.8% -98 dBm 100.0% 100.0% 96.8% 93.5% -74 dBm
Hillsborough, CA 100.0% 100.0% 75.2% 40.0% -96 dBm 100.0% 99.3% 97.9% 57.2% -104 dBm 96.6% 96.6% 93.1% 81.4% -88 dBm
La Honda, CA 97.0% 97.0% 53.5% 43.4% -92 dBm 83.8% 83.8% 0.0% 0.0% -103 dBm 92.9% 91.9% 92.9% 83.8% -81 dBm
Ladera, CA 100.0% 100.0% 90.9% 45.5% -101 dBm 100.0% 100.0% 100.0% 90.9% -110 dBm 100.0% 100.0% 100.0% 100.0% -92 dBm
Loma Mar, CA 25.6% 23.3% 11.6% 11.6% -108 dBm 30.2% 30.2% 4.7% 2.3% -120 dBm N/A N/A N/A N/A N/A
Menlo Park, CA 100.0% 100.0% 96.3% 86.3% -86 dBm 99.2% 98.3% 99.2% 83.8% -98 dBm 99.6% 99.2% 99.6% 95.9% -83 dBm
Millbrae, CA 100.0% 100.0% 100.0% 87.0% -86 dBm 100.0% 100.0% 98.7% 57.1% -97 dBm 100.0% 100.0% 98.7% 96.1% -75 dBm
Montara, CA 86.0% 86.0% 20.4% 3.2% -100 dBm 90.3% 90.3% 4.3% 3.2% -112 dBm 52.7% 48.4% 46.2% 23.7% -94 dBm
Moss Beach, CA 96.4% 96.4% 58.2% 34.5% -92 dBm 96.4% 96.4% 80.0% 63.6% -111 dBm 87.3% 87.3% 85.5% 72.7% -85 dBm
North Fair Oaks, CA 100.0% 100.0% 100.0% 96.3% -78 dBm 100.0% 100.0% 100.0% 70.4% -94 dBm 100.0% 100.0% 100.0% 100.0% -71 dBm
Pacifica, CA 100.0% 100.0% 75.6% 60.3% -87 dBm 99.7% 99.7% 69.2% 56.3% -106 dBm 92.5% 90.5% 87.5% 75.3% -83 dBm
Pescadero, CA 97.9% 97.9% 51.0% 37.5% -96 dBm 94.8% 94.8% 81.3% 72.9% -109 dBm 55.2% 55.2% 0.0% 0.0% -88 dBm
Portola Valley, CA 99.5% 99.5% 32.7% 17.1% -93 dBm 92.4% 91.5% 42.7% 11.8% -110 dBm 85.8% 84.8% 80.1% 50.7% -91 dBm
Redwood City, CA 100.0% 100.0% 97.2% 90.2% -85 dBm 98.3% 98.0% 97.2% 49.8% -100 dBm 98.9% 98.9% 98.9% 98.3% -80 dBm
San Bruno, CA 100.0% 100.0% 96.9% 86.0% -85 dBm 99.2% 99.2% 98.4% 54.3% -99 dBm 100.0% 100.0% 96.9% 89.1% -81 dBm
San Carlos, CA 100.0% 100.0% 89.5% 64.5% -89 dBm 97.6% 97.6% 96.0% 65.3% -99 dBm 100.0% 100.0% 100.0% 100.0% -79 dBm
San Gregorio, CA 68.8% 68.8% 2.2% 1.1% -94 dBm 58.3% 58.3% 23.1% 18.9% -110 dBm 24.4% 19.8% 24.0% 9.7% -95 dBm
San Mateo, CA 100.0% 100.0% 94.7% 87.0% -86 dBm 99.6% 99.6% 98.9% 67.3% -97 dBm 99.6% 99.6% 98.9% 97.2% -78 dBm
South San Francisco, CA 100.0% 100.0% 98.6% 94.8% -81 dBm 99.1% 99.1% 97.2% 57.3% -96 dBm 99.5% 99.5% 93.4% 82.5% -84 dBm
West Menlo Park, CA 100.0% 100.0% 90.0% 60.0% -90 dBm 100.0% 100.0% 100.0% 70.0% -99 dBm 100.0% 100.0% 100.0% 100.0% -82 dBm
Woodside, CA 100.0% 100.0% 57.5% 38.4% -93 dBm 96.3% 96.3% 78.4% 46.6% -107 dBm 90.7% 89.6% 70.1% 34.7% -95 dBm
Palo Alto, CA 94.2% 94.2% 75.4% 55.6% -93 dBm 81.3% 80.5% 68.8% 54.4% -103 dBm 82.0% 81.9% 78.9% 61.6% -89 dBm
San Francisco, CA 99.8% 99.8% 98.9% 92.5% -86 dBm 99.2% 99.1% 98.3% 68.7% -95 dBm 99.2% 99.2% 95.9% 90.1% -80 dBm
Stanford, CA 100.0% 100.0% 69.2% 40.0% -91 dBm 100.0% 100.0% 96.9% 70.8% -95 dBm 96.9% 95.4% 96.9% 80.0% -90 dBm

About The Coverage Data

Coverage and signal estimates are derived by Compare Wireless Carriers from carrier-reported data in the FCC’s National Broadband Coverage Map, last updated in June 2025. “Percent covered” shows how much of the city or ZIP code area has a carrier signal, whether weak or strong. Signal bars show the estimated average signal strength in areas of San Mateo County, CA where that carrier has coverage.

If a carrier says you should have service but you do not, run a challenge test with the FCC Mobile Speed Test App. The FCC uses those results to check carrier-submitted coverage data and requires a carrier response when enough tests show a pattern of inaccurate coverage reporting.