Coverage rankings for Dewey County, SD
AT&T currently ranks first for coverage in this area, with a coverage score of 56.0. 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 | AT&T | 56.0 | 68.6% | 65.6% | 43.5% | 36.2% | -117 dBm |
| 2 | T-Mobile | 50.5 | 61.7% | 61.7% | 32.5% | 17.4% | -98 dBm |
| 3 | Verizon | 46.7 | 75.8% | 75.8% | 4.4% | 2.3% | -98 dBm |
Scores include coverage area, network type, and average signal strength.
Cell phone coverage map for Dewey County, SD
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.
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 Dewey County, SD
AT&T
- Overall
- 68.6%
- 4G LTE
- 65.6%
- 5G
- 43.5%
- Fast 5G
- 36.2%
T-Mobile
- Overall
- 61.7%
- 4G LTE
- 61.7%
- 5G
- 32.5%
- Fast 5G
- 17.4%
Verizon
- Overall
- 75.8%
- 4G LTE
- 75.8%
- 5G
- 4.4%
- Fast 5G
- 2.3%
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.
Pricing, network access, switching terms, and home internet availability may vary.
Coverage by city in Dewey County, SD
Cities and towns are shown for county-level comparison. Coverage percentages use land-area only coverage.
| City | Verizon | AT&T | T-Mobile |
|---|---|---|---|
| Glencross, SD | 65.7% 65.7% 1.0% 0.0% -101 dBm | 63.8% 63.8% 42.0% 40.8% -116 dBm | 62.8% 62.8% 38.5% 24.2% -99 dBm |
| Green Grass, SD | 98.0% 98.0% 28.4% 7.5% -100 dBm | 32.3% 32.3% 13.4% 9.5% -120 dBm | 19.9% 19.9% 5.5% 2.5% -107 dBm |
| Isabel, SD | 100.0% 100.0% 0.0% 0.0% -96 dBm | 100.0% 100.0% 90.5% 90.5% -118 dBm | 4.8% 4.8% 0.0% 0.0% -110 dBm |
| La Plant, SD | 96.2% 96.2% 0.0% 0.0% -99 dBm | 40.4% 40.4% 6.8% 6.8% -120 dBm | 47.7% 47.7% 30.2% 9.4% -102 dBm |
| Lantry, SD | 100.0% 100.0% 0.0% 0.0% -94 dBm | 100.0% 100.0% 91.7% 91.7% -118 dBm | 100.0% 100.0% 100.0% 66.7% -94 dBm |
| North Eagle Butte, SD | 100.0% 100.0% 0.0% 0.0% -74 dBm | 100.0% 100.0% 100.0% 87.7% -97 dBm | 100.0% 100.0% 100.0% 100.0% -74 dBm |
| Ridgeview, SD | 68.8% 68.8% 1.8% 0.2% -99 dBm | 74.5% 69.3% 56.8% 47.2% -116 dBm | 68.6% 68.6% 30.4% 14.4% -98 dBm |
| Swift Bird, SD | 100.0% 100.0% 0.0% 0.0% -97 dBm | 100.0% 100.0% 63.6% 63.6% -115 dBm | 100.0% 100.0% 100.0% 36.4% -97 dBm |
| Timber Lake, SD | 100.0% 100.0% 0.0% 0.0% -73 dBm | 100.0% 100.0% 100.0% 100.0% -93 dBm | 100.0% 100.0% 100.0% 100.0% -74 dBm |
| Whitehorse, SD | 9.4% 9.4% 0.0% 0.0% -107 dBm | 12.5% 12.5% 3.1% 3.1% -120 dBm | 20.3% 20.3% 0.0% 0.0% -105 dBm |
| Eagle Butte, SD | 100.0% 100.0% 0.0% 0.0% -79 dBm | 100.0% 100.0% 100.0% 94.1% -99 dBm | 100.0% 100.0% 100.0% 100.0% -80 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 Dewey County, SD 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.