Casa de Oro-Mount Helix, CA Cell Phone Coverage Map & Network Rankings (2026)

Don’t overpay for a network that struggles where you actually use your phone.

Using FCC mobile coverage data across Casa de Oro-Mount Helix, CA zip codes, this guide compares the top-performing networks and the cheapest plans that use them.

Coverage rankings for Casa de Oro-Mount Helix, CA

T-Mobile currently ranks first for coverage in this area, with a coverage score of 98.0. Carrierlytics 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 T-Mobile 98.0 100.0% 100.0% 99.3% 94.1% -83 dBm
2 Verizon 96.3 100.0% 100.0% 100.0% 94.1% -93 dBm
3 AT&T 87.9 100.0% 100.0% 98.0% 64.5% -105 dBm

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


Cell phone coverage map for Casa de Oro-Mount Helix, 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 Carrierlytics.

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Cell phone coverage by network in Casa de Oro-Mount Helix, CA

#1

T-Mobile

Coverage Score 98.0
In Casa de Oro-Mount Helix, CA
Overall
100.0%
4G LTE
100.0%
5G
99.3%
Fast 5G
94.1%
Average Signal -83 dBm
San Diego County, CA covered 71.7%
#2

Verizon

Coverage Score 96.3
In Casa de Oro-Mount Helix, CA
Overall
100.0%
4G LTE
100.0%
5G
100.0%
Fast 5G
94.1%
Average Signal -93 dBm
San Diego County, CA covered 77.7%
#3

AT&T

Coverage Score 87.9
In Casa de Oro-Mount Helix, CA
Overall
100.0%
4G LTE
100.0%
5G
98.0%
Fast 5G
64.5%
Average Signal -105 dBm
San Diego County, CA covered 73.4%

County coverage is shown for surrounding-area context and uses land-area only coverage.

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Coverage by ZIP code in Casa de Oro-Mount Helix, CA

ZIP code areas can extend beyond city limits, so this table is best used for local comparison around the city.

ZIP Code AT&T T-Mobile Verizon
91941 99.4% 99.4% 98.9% 68.2% -103 dBm 100.0% 100.0% 96.1% 91.6% -82 dBm 100.0% 100.0% 100.0% 91.1% -94 dBm
91977 100.0% 100.0% 99.1% 72.0% -104 dBm 100.0% 100.0% 99.5% 99.5% -79 dBm 100.0% 100.0% 99.5% 93.6% -92 dBm
92019 96.8% 96.8% 89.1% 73.8% -102 dBm 96.3% 96.3% 92.4% 85.8% -82 dBm 98.8% 98.8% 93.7% 82.1% -94 dBm
92020 99.6% 99.6% 98.3% 71.4% -99 dBm 100.0% 100.0% 99.2% 94.2% -79 dBm 100.0% 100.0% 100.0% 98.3% -85 dBm

About The Coverage Data

Coverage and signal estimates are derived by Carrierlytics 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 Casa de Oro-Mount Helix, 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.