Sangamon County, IL Cell Phone Coverage Map & Network Rankings (2026)

Find the best cell phone network and plan to use in Sangamon County, IL

Coverage rankings for Sangamon County, IL

T-Mobile currently ranks first for coverage in this area, with a coverage score of 92.2. Compare Wireless Carriers uses FCC broadband map data to estimate and calculate coverage scores. More on that further below.

RankCarrierScoreOverall4G LTE5GFast 5GAverage Signal
1T-Mobile92.295.7%95.7%90.6%76.8% -88 dBm
2AT&T86.498.9%98.7%93.6%61.4% -107 dBm
3Verizon85.399.1%99.0%68.2%52.1% -91 dBm

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

Cell phone coverage map for Sangamon County, IL

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 Sangamon County, IL

#1

T-Mobile

Coverage Score 92.2
In Sangamon County, IL
Overall
95.7%
4G LTE
95.7%
5G
90.6%
Fast 5G
76.8%
Average Signal -88 dBm
#2

AT&T

Coverage Score 86.4
In Sangamon County, IL
Overall
98.9%
4G LTE
98.7%
5G
93.6%
Fast 5G
61.4%
Average Signal -107 dBm
#3

Verizon

Coverage Score 85.3
In Sangamon County, IL
Overall
99.1%
4G LTE
99.0%
5G
68.2%
Fast 5G
52.1%
Average Signal -91 dBm
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Coverage by city in Sangamon County, IL

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

CityVerizonAT&TT-Mobile
Auburn, IL 100.0% 100.0% 55.1% 41.1% -87 dBm 100.0% 100.0% 100.0% 96.3% -97 dBm 100.0% 100.0% 100.0% 98.1% -76 dBm
Berlin, IL 100.0% 100.0% 100.0% 95.7% -92 dBm 100.0% 100.0% 100.0% 100.0% -102 dBm 100.0% 100.0% 100.0% 78.3% -87 dBm
Buffalo, IL 100.0% 100.0% 66.7% 0.0% -98 dBm 100.0% 100.0% 66.7% 66.7% -116 dBm 100.0% 100.0% 100.0% 100.0% -87 dBm
Cantrall, IL 100.0% 100.0% 0.0% 0.0% -106 dBm 100.0% 100.0% 100.0% 100.0% -106 dBm 100.0% 100.0% 40.0% 0.0% -100 dBm
Chatham, IL 100.0% 100.0% 87.5% 75.5% -88 dBm 100.0% 100.0% 100.0% 70.1% -98 dBm 100.0% 100.0% 98.9% 90.8% -84 dBm
Curran, IL 100.0% 100.0% 100.0% 100.0% -73 dBm 100.0% 100.0% 100.0% 95.9% -98 dBm 100.0% 100.0% 100.0% 100.0% -72 dBm
Dawson, IL 100.0% 100.0% 100.0% 90.0% -94 dBm 100.0% 100.0% 100.0% 100.0% -102 dBm 100.0% 100.0% 95.0% 80.0% -88 dBm
Divernon, IL 100.0% 100.0% 82.4% 58.8% -89 dBm 100.0% 100.0% 100.0% 94.1% -104 dBm 100.0% 100.0% 100.0% 76.5% -89 dBm
Grandview, IL 100.0% 100.0% 9.1% 9.1% -76 dBm 100.0% 100.0% 100.0% 54.5% -95 dBm 100.0% 100.0% 100.0% 100.0% -72 dBm
Illiopolis, IL 100.0% 100.0% 16.7% 11.1% -77 dBm 100.0% 100.0% 44.4% 44.4% -109 dBm 100.0% 100.0% 88.9% 38.9% -98 dBm
Jerome, IL 100.0% 100.0% 100.0% 90.9% -85 dBm 100.0% 100.0% 100.0% 63.6% -92 dBm 100.0% 100.0% 100.0% 100.0% -74 dBm
Leland Grove, IL 100.0% 100.0% 73.3% 33.3% -96 dBm 100.0% 100.0% 100.0% 40.0% -99 dBm 100.0% 100.0% 100.0% 100.0% -83 dBm
Loami, IL 92.3% 92.3% 50.0% 38.5% -100 dBm 100.0% 100.0% 96.2% 42.3% -115 dBm 100.0% 100.0% 100.0% 100.0% -70 dBm
Mechanicsburg, IL 100.0% 100.0% 23.1% 0.0% -91 dBm 88.5% 88.5% 30.8% 26.9% -115 dBm 100.0% 100.0% 92.3% 50.0% -93 dBm
New Berlin, IL 100.0% 100.0% 96.4% 96.4% -82 dBm 100.0% 100.0% 100.0% 75.0% -110 dBm 100.0% 100.0% 100.0% 100.0% -85 dBm
Pawnee, IL 100.0% 100.0% 87.1% 71.0% -91 dBm 100.0% 100.0% 100.0% 93.5% -90 dBm 35.5% 35.5% 25.8% 16.1% -97 dBm
Pleasant Plains, IL 100.0% 100.0% 8.3% 5.6% -102 dBm 100.0% 100.0% 100.0% 97.2% -89 dBm 100.0% 100.0% 100.0% 100.0% -78 dBm
Riverton, IL 100.0% 100.0% 75.6% 61.0% -87 dBm 100.0% 100.0% 100.0% 87.8% -103 dBm 100.0% 100.0% 100.0% 95.1% -78 dBm
Rochester, IL 100.0% 100.0% 47.8% 30.4% -92 dBm 100.0% 100.0% 100.0% 97.1% -94 dBm 100.0% 100.0% 100.0% 92.8% -79 dBm
Sherman, IL 100.0% 100.0% 40.7% 9.9% -94 dBm 100.0% 100.0% 98.8% 86.4% -94 dBm 100.0% 100.0% 100.0% 92.6% -86 dBm
Southern View, IL 100.0% 100.0% 87.5% 62.5% -92 dBm 100.0% 100.0% 100.0% 50.0% -94 dBm 100.0% 100.0% 100.0% 100.0% -76 dBm
Spaulding, IL 100.0% 100.0% 66.7% 55.6% -93 dBm 100.0% 100.0% 100.0% 100.0% -96 dBm 100.0% 100.0% 100.0% 100.0% -87 dBm
Springfield, IL 99.6% 99.6% 76.2% 61.1% -88 dBm 100.0% 99.9% 99.0% 61.2% -98 dBm 100.0% 100.0% 99.4% 94.2% -81 dBm
Thayer, IL 100.0% 100.0% 71.4% 57.1% -96 dBm 100.0% 100.0% 100.0% 100.0% -105 dBm 100.0% 100.0% 100.0% 85.7% -89 dBm
Williamsville, IL 100.0% 100.0% 100.0% 100.0% -80 dBm 100.0% 100.0% 100.0% 95.7% -96 dBm 100.0% 100.0% 100.0% 91.3% -88 dBm
Ashland, IL 100.0% 100.0% 0.0% 0.0% -73 dBm 100.0% 100.0% 100.0% 47.4% -87 dBm 84.2% 84.2% 36.8% 21.1% -103 dBm
Virden, IL 100.0% 100.0% 97.8% 84.8% -85 dBm 100.0% 100.0% 100.0% 91.3% -93 dBm 100.0% 100.0% 100.0% 100.0% -76 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 Sangamon County, IL 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.