Highest Radon Risk ZIP Codes in Wyoming — 2026

Out of 185 ZIP codes with data in Wyoming, these are the lowest-ranked areas for radon zone. See also: National ZIP Codes with Highest Radon Risk | All Wyoming Rankings

Statistic	Value
ZIP codes ranked	185
Lowest value	Zone 1 (High)
Median value	Zone 1 (High)
State	Wyoming

100 Lowest-Ranked ZIP Codes

Rank	ZIP Code	City	State	Radon Zone	Safety Score
1	82501	Riverton	WY	Zone 1 (High)	36/100
2	82520	Lander	WY	Zone 1 (High)	49/100
3	82301	Rawlins	WY	Zone 1 (High)	53/100
4	83101	Kemmerer	WY	Zone 1 (High)	60/100
5	83116	Diamondville	WY	Zone 1 (High)	60/100
6	82834	Buffalo	WY	Zone 1 (High)	62/100
7	82001	Cheyenne	WY	Zone 1 (High)	63/100
8	82604	Casper	WY	Zone 1 (High)	63/100
9	83001	Jackson	WY	Zone 1 (High)	63/100
10	82601	Casper	WY	Zone 1 (High)	64/100
11	82716	Gillette	WY	Zone 1 (High)	64/100
12	82005	Fe Warren Afb	WY	Zone 1 (High)	65/100
13	82009	Cheyenne	WY	Zone 1 (High)	65/100
14	82644	Mills	WY	Zone 1 (High)	65/100
15	82007	Cheyenne	WY	Zone 1 (High)	66/100
16	82070	Laramie	WY	Zone 1 (High)	66/100
17	82072	Laramie	WY	Zone 1 (High)	66/100
18	82414	Cody	WY	Zone 1 (High)	66/100
19	82609	Casper	WY	Zone 1 (High)	66/100
20	82718	Gillette	WY	Zone 1 (High)	66/100
21	82727	Rozet	WY	Zone 1 (High)	66/100
22	82901	Rock Springs	WY	Zone 1 (High)	66/100
23	82930	Evanston	WY	Zone 1 (High)	66/100
24	82935	Green River	WY	Zone 1 (High)	66/100
25	82401	Worland	WY	Zone 1 (High)	67/100
26	82435	Powell	WY	Zone 1 (High)	67/100
27	82633	Douglas	WY	Zone 1 (High)	67/100
28	82801	Sheridan	WY	Zone 1 (High)	67/100
29	82943	Reliance	WY	Zone 1 (High)	67/100
30	82002	Cheyenne	WY	Zone 1 (High)	—
31	82003	Cheyenne	WY	Zone 1 (High)	—
32	82006	Cheyenne	WY	Zone 1 (High)	—
33	82008	Cheyenne	WY	Zone 1 (High)	—
34	82010	Cheyenne	WY	Zone 1 (High)	—
35	82050	Albin	WY	Zone 1 (High)	—
36	82051	Bosler	WY	Zone 1 (High)	—
37	82052	Buford	WY	Zone 1 (High)	—
38	82053	Burns	WY	Zone 1 (High)	—
39	82054	Carpenter	WY	Zone 1 (High)	—
40	82055	Centennial	WY	Zone 1 (High)	—
41	82058	Garrett	WY	Zone 1 (High)	—
42	82059	Granite Canon	WY	Zone 1 (High)	—
43	82060	Hillsdale	WY	Zone 1 (High)	—
44	82061	Horse Creek	WY	Zone 1 (High)	—
45	82063	Jelm	WY	Zone 1 (High)	—
46	82071	Laramie	WY	Zone 1 (High)	—
47	82073	Laramie	WY	Zone 1 (High)	—
48	82081	Meriden	WY	Zone 1 (High)	—
49	82082	Pine Bluffs	WY	Zone 1 (High)	—
50	82083	Rock River	WY	Zone 1 (High)	—
51	82084	Tie Siding	WY	Zone 1 (High)	—
52	82190	Yellowstone National Park	WY	Zone 1 (High)	—
53	82212	Fort Laramie	WY	Zone 1 (High)	—
54	82217	Hawk Springs	WY	Zone 1 (High)	—
55	82218	Huntley	WY	Zone 1 (High)	—
56	82221	Lagrange	WY	Zone 1 (High)	—
57	82222	Lance Creek	WY	Zone 1 (High)	—
58	82223	Lingle	WY	Zone 1 (High)	—
59	82224	Lost Springs	WY	Zone 1 (High)	—
60	82225	Lusk	WY	Zone 1 (High)	—
61	82227	Manville	WY	Zone 1 (High)	—
62	82229	Shawnee	WY	Zone 1 (High)	—
63	82240	Torrington	WY	Zone 1 (High)	—
64	82242	Van Tassell	WY	Zone 1 (High)	—
65	82243	Veteran	WY	Zone 1 (High)	—
66	82244	Yoder	WY	Zone 1 (High)	—
67	82310	Jeffrey City	WY	Zone 1 (High)	—
68	82321	Baggs	WY	Zone 1 (High)	—
69	82322	Bairoil	WY	Zone 1 (High)	—
70	82323	Dixon	WY	Zone 1 (High)	—
71	82324	Elk Mountain	WY	Zone 1 (High)	—
72	82325	Encampment	WY	Zone 1 (High)	—
73	82327	Hanna	WY	Zone 1 (High)	—
74	82329	Medicine Bow	WY	Zone 1 (High)	—
75	82331	Saratoga	WY	Zone 1 (High)	—
76	82332	Savery	WY	Zone 1 (High)	—
77	82334	Sinclair	WY	Zone 1 (High)	—
78	82335	Walcott	WY	Zone 1 (High)	—
79	82336	Wamsutter	WY	Zone 1 (High)	—
80	82410	Basin	WY	Zone 1 (High)	—
81	82411	Burlington	WY	Zone 1 (High)	—
82	82412	Byron	WY	Zone 1 (High)	—
83	82420	Cowley	WY	Zone 1 (High)	—
84	82421	Deaver	WY	Zone 1 (High)	—
85	82422	Emblem	WY	Zone 1 (High)	—
86	82423	Frannie	WY	Zone 1 (High)	—
87	82426	Greybull	WY	Zone 1 (High)	—
88	82428	Hyattville	WY	Zone 1 (High)	—
89	82430	Kirby	WY	Zone 1 (High)	—
90	82431	Lovell	WY	Zone 1 (High)	—
91	82432	Manderson	WY	Zone 1 (High)	—
92	82433	Meeteetse	WY	Zone 1 (High)	—
93	82434	Otto	WY	Zone 1 (High)	—
94	82440	Ralston	WY	Zone 1 (High)	—
95	82441	Shell	WY	Zone 1 (High)	—
96	82442	Ten Sleep	WY	Zone 1 (High)	—
97	82443	Thermopolis	WY	Zone 1 (High)	—
98	82450	Wapiti	WY	Zone 1 (High)	—
99	82510	Arapahoe	WY	Zone 1 (High)	—
100	82512	Crowheart	WY	Zone 1 (High)	—

Methodology

Radon rankings are based on EPA county-level radon zone classifications. Zone 1 (highest risk) has predicted average indoor radon levels above 4 pCi/L — the EPA action level. Zone 2 is moderate (2-4 pCi/L) and Zone 3 is low (below 2 pCi/L). Within Zone 1, ZIP codes are sub-ranked by Home Safety Score to prioritize areas with compounding risk factors.

Data sources: EPA Safe Drinking Water Information System (SDWIS), FEMA National Flood Insurance Program, EPA radon zone maps, EIA electricity rates, and Consumer Confidence Reports. Last updated: 2026-08-14.

Frequently Asked Questions

What is EPA Radon Zone 1?

Zone 1 is the EPA highest-risk classification, meaning the county has predicted average indoor radon levels above 4 pCi/L — the level at which the EPA recommends mitigation. Radon causes about 21,000 lung cancer deaths per year in the U.S.

Should I test for radon?

The EPA recommends testing all homes regardless of radon zone. A DIY test kit costs $15-40. Professional testing costs $150-250. If levels exceed 4 pCi/L, mitigation systems ($800-2,500) can reduce radon by up to 99%.