Coverage rankings for Contra Costa County, CA
Verizon currently ranks first for coverage in this area, with a coverage score of 89.3. Compare Wireless Carriers uses FCC broadband map data to estimate and calculate coverage scores. More on that further below.
| Rank | Carrier | Score | Overall | 4G LTE | 5G | Fast 5G | Average Signal |
|---|---|---|---|---|---|---|---|
| 1 | Verizon | 89.3 | 97.7% | 97.7% | 79.3% | 66.3% | -90 dBm |
| 2 | T-Mobile | 86.3 | 87.8% | 87.0% | 82.5% | 69.1% | -86 dBm |
| 3 | AT&T | 78.7 | 92.0% | 91.7% | 78.7% | 51.9% | -109 dBm |
Scores include coverage area, network type, and average signal strength.
Cell phone coverage map for Contra Costa 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.
Loading coverage map...
Cell phone coverage by network in Contra Costa County, CA
#1
Verizon
Coverage Score 89.3
In Contra Costa County, CA
- Overall
- 97.7%
- 4G LTE
- 97.7%
- 5G
- 79.3%
- Fast 5G
- 66.3%
Average Signal -90 dBm
#2
T-Mobile
Coverage Score 86.3
In Contra Costa County, CA
- Overall
- 87.8%
- 4G LTE
- 87.0%
- 5G
- 82.5%
- Fast 5G
- 69.1%
Average Signal -86 dBm
#3
AT&T
Coverage Score 78.7
In Contra Costa County, CA
- Overall
- 92.0%
- 4G LTE
- 91.7%
- 5G
- 78.7%
- Fast 5G
- 51.9%
Average Signal -109 dBm
Sponsored US Mobile
Coverage varies by neighborhood. Your carrier shouldn’t.
US Mobile lets you switch between all three major networks, so you can choose the one that works best where you actually use your phone.
Choose your network
Dark Star Light Speed Warp 5G
Unlimited plans from
$22.50/mo
Phone + home internet bundle from
$47/mo
Shop US Mobile
Pricing, network access, switching terms, and home internet availability may vary.
Coverage by city in Contra Costa County, CA
Cities and towns are shown for county-level comparison. Coverage percentages use land-area only coverage.
| City | Verizon | AT&T | T-Mobile |
|---|---|---|---|
| Acalanes Ridge, CA | 100.0% 100.0% 100.0% 88.9% -84 dBm | 77.8% 77.8% 77.8% 44.4% -109 dBm | 100.0% 100.0% 100.0% 100.0% -83 dBm |
| Alamo, CA | 100.0% 100.0% 95.7% 81.7% -91 dBm | 98.7% 98.7% 92.2% 70.0% -111 dBm | 99.1% 98.3% 75.2% 43.5% -92 dBm |
| Alhambra Valley, CA | 100.0% 100.0% 90.2% 68.3% -92 dBm | 78.0% 78.0% 22.0% 0.0% -118 dBm | 70.7% 70.7% 63.4% 43.9% -88 dBm |
| Antioch, CA | 100.0% 100.0% 92.4% 85.7% -85 dBm | 98.3% 98.3% 94.3% 71.0% -104 dBm | 99.6% 99.6% 99.4% 97.5% -79 dBm |
| Bay Point, CA | 100.0% 100.0% 96.7% 87.6% -84 dBm | 100.0% 100.0% 100.0% 78.4% -102 dBm | 100.0% 100.0% 100.0% 98.7% -79 dBm |
| Bayview, CA | 100.0% 100.0% 100.0% 71.4% -96 dBm | 100.0% 100.0% 100.0% 85.7% -96 dBm | 100.0% 100.0% 100.0% 100.0% -89 dBm |
| Bethel Island, CA | 100.0% 100.0% 95.3% 82.2% -88 dBm | 100.0% 100.0% 100.0% 98.4% -103 dBm | 90.7% 90.7% 79.8% 28.7% -98 dBm |
| Blackhawk, CA | 100.0% 100.0% 71.5% 54.7% -95 dBm | 100.0% 100.0% 92.7% 86.9% -109 dBm | 97.8% 97.8% 96.4% 90.5% -84 dBm |
| Brentwood, CA | 100.0% 100.0% 98.3% 92.0% -83 dBm | 99.7% 99.7% 98.9% 77.4% -104 dBm | 100.0% 100.0% 100.0% 98.3% -81 dBm |
| Byron, CA | 100.0% 100.0% 100.0% 97.4% -84 dBm | 100.0% 100.0% 100.0% 96.1% -105 dBm | 100.0% 100.0% 100.0% 100.0% -79 dBm |
| Camino Tassajara, CA | 100.0% 100.0% 86.7% 60.0% -99 dBm | 100.0% 100.0% 86.7% 80.0% -118 dBm | 100.0% 100.0% 100.0% 90.0% -86 dBm |
| Canyon, CA | 97.6% 97.6% 37.6% 24.7% -101 dBm | 83.5% 82.4% 40.0% 17.6% -116 dBm | 45.9% 45.9% 34.1% 12.9% -99 dBm |
| Castle Hill, CA | 100.0% 100.0% 73.3% 66.7% -92 dBm | 100.0% 100.0% 93.3% 33.3% -117 dBm | 100.0% 100.0% 100.0% 100.0% -86 dBm |
| Clayton, CA | 100.0% 100.0% 97.7% 86.4% -86 dBm | 100.0% 100.0% 98.9% 83.0% -109 dBm | 100.0% 100.0% 100.0% 94.3% -80 dBm |
| Clyde, CA | 100.0% 100.0% 100.0% 100.0% -83 dBm | 100.0% 100.0% 100.0% 100.0% -103 dBm | 100.0% 100.0% 100.0% 100.0% -83 dBm |
| Concord, CA | 100.0% 100.0% 99.7% 97.9% -83 dBm | 98.9% 98.7% 97.6% 56.3% -108 dBm | 100.0% 100.0% 99.6% 95.0% -82 dBm |
| Contra Costa Centre, CA | 100.0% 100.0% 100.0% 100.0% -78 dBm | 100.0% 100.0% 100.0% 73.3% -113 dBm | 100.0% 100.0% 100.0% 86.7% -87 dBm |
| Crockett, CA | 100.0% 100.0% 100.0% 96.2% -83 dBm | 100.0% 100.0% 100.0% 80.8% -105 dBm | 100.0% 100.0% 100.0% 100.0% -80 dBm |
| Danville, CA | 100.0% 100.0% 89.2% 78.8% -92 dBm | 100.0% 100.0% 97.9% 90.8% -105 dBm | 99.8% 99.8% 98.8% 87.5% -86 dBm |
| Diablo, CA | 100.0% 100.0% 87.9% 78.8% -95 dBm | 100.0% 100.0% 87.9% 84.8% -113 dBm | 90.9% 90.9% 90.9% 72.7% -86 dBm |
| Discovery Bay, CA | 100.0% 100.0% 98.5% 96.2% -81 dBm | 100.0% 100.0% 100.0% 87.9% -104 dBm | 100.0% 100.0% 100.0% 100.0% -83 dBm |
| East Richmond Heights, CA | 100.0% 100.0% 69.2% 69.2% -95 dBm | 92.3% 92.3% 61.5% 23.1% -111 dBm | 84.6% 84.6% 84.6% 76.9% -85 dBm |
| El Cerrito, CA | 100.0% 100.0% 97.8% 96.6% -82 dBm | 100.0% 98.9% 100.0% 50.6% -101 dBm | 100.0% 100.0% 100.0% 97.8% -80 dBm |
| El Sobrante, CA | 100.0% 100.0% 86.3% 69.9% -84 dBm | 100.0% 100.0% 100.0% 67.1% -104 dBm | 100.0% 100.0% 100.0% 94.5% -85 dBm |
| Hercules, CA | 100.0% 100.0% 92.8% 82.9% -86 dBm | 99.3% 99.3% 89.5% 60.5% -109 dBm | 96.7% 96.7% 88.8% 85.5% -83 dBm |
| Kensington, CA | 100.0% 100.0% 90.9% 86.4% -91 dBm | 100.0% 100.0% 90.9% 31.8% -104 dBm | 95.5% 95.5% 95.5% 90.9% -90 dBm |
| Knightsen, CA | 100.0% 100.0% 100.0% 98.5% -83 dBm | 100.0% 100.0% 100.0% 86.7% -107 dBm | 100.0% 100.0% 100.0% 89.2% -91 dBm |
| Lafayette, CA | 100.0% 100.0% 88.1% 72.0% -93 dBm | 98.3% 98.3% 84.5% 59.9% -112 dBm | 93.8% 93.5% 77.4% 55.9% -91 dBm |
| Martinez, CA | 100.0% 100.0% 96.6% 87.6% -86 dBm | 97.7% 97.7% 91.6% 74.2% -106 dBm | 99.0% 99.0% 96.6% 82.9% -85 dBm |
| Montalvin Manor, CA | 100.0% 100.0% 87.5% 50.0% -96 dBm | 100.0% 100.0% 100.0% 100.0% -96 dBm | 100.0% 100.0% 100.0% 87.5% -90 dBm |
| Moraga, CA | 100.0% 100.0% 92.4% 84.3% -87 dBm | 100.0% 100.0% 65.9% 52.9% -110 dBm | 92.8% 92.4% 92.4% 79.8% -87 dBm |
| Mountain View, CA | 100.0% 100.0% 100.0% 100.0% -80 dBm | 100.0% 100.0% 100.0% 100.0% -97 dBm | 100.0% 100.0% 100.0% 100.0% -79 dBm |
| Norris Canyon, CA | 100.0% 100.0% 95.2% 90.5% -92 dBm | 98.8% 98.8% 94.0% 76.2% -107 dBm | 98.8% 97.6% 98.8% 90.5% -79 dBm |
| North Gate, CA | 100.0% 100.0% 100.0% 85.0% -95 dBm | 100.0% 100.0% 80.0% 15.0% -117 dBm | 100.0% 100.0% 100.0% 85.0% -93 dBm |
| North Richmond, CA | 100.0% 100.0% 100.0% 97.1% -81 dBm | 100.0% 100.0% 97.1% 76.5% -99 dBm | 100.0% 100.0% 100.0% 97.1% -74 dBm |
| Oakley, CA | 100.0% 100.0% 99.7% 99.2% -80 dBm | 100.0% 100.0% 100.0% 93.9% -103 dBm | 100.0% 100.0% 100.0% 91.5% -84 dBm |
| Orinda, CA | 100.0% 100.0% 82.1% 61.5% -92 dBm | 99.7% 99.7% 91.4% 72.4% -110 dBm | 90.4% 89.4% 70.8% 45.2% -93 dBm |
| Pacheco, CA | 100.0% 100.0% 100.0% 100.0% -77 dBm | 100.0% 100.0% 100.0% 60.0% -109 dBm | 100.0% 100.0% 100.0% 100.0% -78 dBm |
| Pinole, CA | 100.0% 100.0% 95.9% 85.4% -84 dBm | 100.0% 100.0% 95.1% 76.4% -106 dBm | 100.0% 100.0% 93.5% 87.8% -82 dBm |
| Pittsburg, CA | 100.0% 100.0% 98.2% 92.8% -82 dBm | 99.3% 99.3% 96.8% 72.6% -104 dBm | 100.0% 100.0% 100.0% 98.6% -80 dBm |
| Pleasant Hill, CA | 100.0% 100.0% 100.0% 95.8% -85 dBm | 100.0% 100.0% 99.4% 64.5% -104 dBm | 100.0% 100.0% 79.5% 64.5% -87 dBm |
| Port Costa, CA | 100.0% 100.0% 66.7% 66.7% -97 dBm | 100.0% 100.0% 100.0% 66.7% -113 dBm | 66.7% 66.7% 33.3% 33.3% -95 dBm |
| Reliez Valley, CA | 100.0% 100.0% 98.2% 89.5% -90 dBm | 100.0% 100.0% 80.7% 42.1% -115 dBm | 93.0% 93.0% 77.2% 57.9% -90 dBm |
| Richmond, CA | 99.6% 99.6% 89.8% 78.5% -87 dBm | 94.9% 94.6% 90.1% 50.8% -105 dBm | 93.9% 93.5% 88.7% 77.8% -84 dBm |
| Rodeo, CA | 100.0% 100.0% 100.0% 90.7% -84 dBm | 100.0% 100.0% 97.7% 80.2% -105 dBm | 98.8% 98.8% 98.8% 75.6% -93 dBm |
| Rollingwood, CA | 100.0% 100.0% 100.0% 100.0% -78 dBm | 100.0% 100.0% 100.0% 100.0% -93 dBm | 100.0% 100.0% 100.0% 100.0% -75 dBm |
| San Miguel, CA | 100.0% 100.0% 100.0% 87.5% -88 dBm | 100.0% 100.0% 100.0% 75.0% -102 dBm | 100.0% 100.0% 100.0% 87.5% -89 dBm |
| San Pablo, CA | 100.0% 100.0% 100.0% 100.0% -77 dBm | 100.0% 100.0% 100.0% 61.9% -96 dBm | 100.0% 100.0% 100.0% 100.0% -78 dBm |
| San Ramon, CA | 100.0% 100.0% 88.9% 80.0% -87 dBm | 99.6% 99.6% 95.9% 77.0% -103 dBm | 100.0% 100.0% 100.0% 97.0% -81 dBm |
| Saranap, CA | 100.0% 100.0% 100.0% 88.5% -86 dBm | 100.0% 100.0% 100.0% 73.1% -100 dBm | 100.0% 100.0% 100.0% 100.0% -89 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 Contra Costa 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.