Carrierlytics City Coverage Guide

Rocky Boy’s Agency, MT 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 Rocky Boy’s Agency, MT ZIP codes, Carrierlytics compares the top-performing networks and the cheapest plans that use them.



Cell phone coverage map for Rocky Boy’s Agency, MT

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 rankings by network in Rocky Boy’s Agency, MT

#1

T-Mobile

Coverage Score 93.5
In Rocky Boy’s Agency, MT
Overall
96.8%
4G LTE
96.8% avg. -86 dBm 4G LTE signal where 4G LTE coverage exists: avg. -86 dBm
5G
93.6% avg. -84 dBm 5G signal where 5G coverage exists: avg. -84 dBm
Fast 5G
84.0% avg. -82 dBm Fast 5G signal where Fast 5G coverage exists: avg. -82 dBm
Hill County, MT covered 58.8%
#2

Verizon

Coverage Score 45.6
In Rocky Boy’s Agency, MT
Overall
95.4%
4G LTE
95.4% avg. -89 dBm 4G LTE signal where 4G LTE coverage exists: avg. -89 dBm
5G
0.0%
Fast 5G
0.0%
Hill County, MT covered 88.7%
#3

AT&T

Coverage Score 27.3
In Rocky Boy’s Agency, MT
Overall
61.2%
4G LTE
61.2% avg. -110 dBm 4G LTE signal where 4G LTE coverage exists: avg. -110 dBm
5G
0.5% avg. -120 dBm 5G signal where 5G coverage exists: avg. -120 dBm
Fast 5G
0.5% avg. -120 dBm Fast 5G signal where Fast 5G coverage exists: avg. -120 dBm
Hill County, MT covered 71.3%

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

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Best phone plans for Rocky Boy's Agency, MT

Best phone plans on T-Mobile's network for Rocky Boy's Agency, MT

93.5 T-Mobile coverage score Ranked #1 in Rocky Boy's Agency, MT
Best family plan
79.5 Value Score

T-Mobile Better Value

Fair Value

Price
$140.01/mo for 3 lines ($46.67/line)
Data
Unlimited
Hotspot
Unlimited
View plan
See all plans on T-Mobile Compare all phone plans

Coverage by ZIP code in Rocky Boy’s Agency, MT

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
59521 78.2% 78.2% 14.8% 11.2% 79.1% 79.1% 70.2% 50.0% 84.5% 84.5% 20.3% 0.1%

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 Rocky Boy’s Agency, MT 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.