Out of 602 ZIP codes with data in Colorado, these are the lowest-ranked areas for radon zone. See also: National ZIP Codes with Highest Radon Risk | All Colorado Rankings
| Statistic | Value |
|---|---|
| ZIP codes ranked | 602 |
| Lowest value | Zone 1 (High) |
| Median value | Zone 1 (High) |
| State | Colorado |
100 Lowest-Ranked ZIP Codes
| Rank | ZIP Code | City | State | Radon Zone | Safety Score |
|---|---|---|---|---|---|
| 1 | 80746 | Paoli | CO | Zone 1 (High) | 31/100 |
| 2 | 81030 | Cheraw | CO | Zone 1 (High) | 33/100 |
| 3 | 81047 | Holly | CO | Zone 1 (High) | 33/100 |
| 4 | 81058 | Manzanola | CO | Zone 1 (High) | 33/100 |
| 5 | 80536 | Livermore | CO | Zone 1 (High) | 34/100 |
| 6 | 81090 | Walsh | CO | Zone 1 (High) | 34/100 |
| 7 | 80540 | Lyons | CO | Zone 1 (High) | 35/100 |
| 8 | 81050 | La Junta | CO | Zone 1 (High) | 35/100 |
| 9 | 81044 | Hasty | CO | Zone 1 (High) | 37/100 |
| 10 | 80024 | Dupont | CO | Zone 1 (High) | 40/100 |
| 11 | 80131 | Louviers | CO | Zone 1 (High) | 40/100 |
| 12 | 80429 | Climax | CO | Zone 1 (High) | 40/100 |
| 13 | 80432 | Como | CO | Zone 1 (High) | 40/100 |
| 14 | 80434 | Cowdrey | CO | Zone 1 (High) | 40/100 |
| 15 | 80448 | Grant | CO | Zone 1 (High) | 40/100 |
| 16 | 80456 | Jefferson | CO | Zone 1 (High) | 40/100 |
| 17 | 80468 | Parshall | CO | Zone 1 (High) | 40/100 |
| 18 | 80471 | Pinecliffe | CO | Zone 1 (High) | 40/100 |
| 19 | 80473 | Rand | CO | Zone 1 (High) | 40/100 |
| 20 | 80475 | Shawnee | CO | Zone 1 (High) | 40/100 |
| 21 | 80533 | Hygiene | CO | Zone 1 (High) | 40/100 |
| 22 | 80535 | Laporte | CO | Zone 1 (High) | 40/100 |
| 23 | 80541 | Masonville | CO | Zone 1 (High) | 40/100 |
| 24 | 80612 | Carr | CO | Zone 1 (High) | 40/100 |
| 25 | 80729 | Grover | CO | Zone 1 (High) | 40/100 |
| 26 | 80732 | Hereford | CO | Zone 1 (High) | 40/100 |
| 27 | 80735 | Idalia | CO | Zone 1 (High) | 40/100 |
| 28 | 80740 | Lindon | CO | Zone 1 (High) | 40/100 |
| 29 | 80745 | Padroni | CO | Zone 1 (High) | 40/100 |
| 30 | 80754 | Stoneham | CO | Zone 1 (High) | 40/100 |
| 31 | 80755 | Vernon | CO | Zone 1 (High) | 40/100 |
| 32 | 80757 | Woodrow | CO | Zone 1 (High) | 40/100 |
| 33 | 80801 | Anton | CO | Zone 1 (High) | 40/100 |
| 34 | 80804 | Arriba | CO | Zone 1 (High) | 40/100 |
| 35 | 80812 | Cope | CO | Zone 1 (High) | 40/100 |
| 36 | 80820 | Guffey | CO | Zone 1 (High) | 40/100 |
| 37 | 80822 | Joes | CO | Zone 1 (High) | 40/100 |
| 38 | 80824 | Kirk | CO | Zone 1 (High) | 40/100 |
| 39 | 80825 | Kit Carson | CO | Zone 1 (High) | 40/100 |
| 40 | 80830 | Matheson | CO | Zone 1 (High) | 40/100 |
| 41 | 80833 | Rush | CO | Zone 1 (High) | 40/100 |
| 42 | 80840 | U S A F Academy | CO | Zone 1 (High) | 40/100 |
| 43 | 80841 | U S A F Academy | CO | Zone 1 (High) | 40/100 |
| 44 | 80862 | Wild Horse | CO | Zone 1 (High) | 40/100 |
| 45 | 81021 | Arlington | CO | Zone 1 (High) | 40/100 |
| 46 | 81024 | Boncarbo | CO | Zone 1 (High) | 40/100 |
| 47 | 81033 | Crowley | CO | Zone 1 (High) | 40/100 |
| 48 | 81034 | Crowley | CO | Zone 1 (High) | 40/100 |
| 49 | 81038 | Fort Lyon | CO | Zone 1 (High) | 40/100 |
| 50 | 81043 | Hartman | CO | Zone 1 (High) | 40/100 |
| 51 | 81046 | Hoehne | CO | Zone 1 (High) | 40/100 |
| 52 | 81057 | Mc Clave | CO | Zone 1 (High) | 40/100 |
| 53 | 81059 | Model | CO | Zone 1 (High) | 40/100 |
| 54 | 81069 | Rye | CO | Zone 1 (High) | 40/100 |
| 55 | 81081 | Trinchera | CO | Zone 1 (High) | 40/100 |
| 56 | 81091 | Weston | CO | Zone 1 (High) | 40/100 |
| 57 | 81121 | Arboles | CO | Zone 1 (High) | 40/100 |
| 58 | 81223 | Cotopaxi | CO | Zone 1 (High) | 40/100 |
| 59 | 81227 | Monarch | CO | Zone 1 (High) | 40/100 |
| 60 | 81228 | Granite | CO | Zone 1 (High) | 40/100 |
| 61 | 81232 | Hillside | CO | Zone 1 (High) | 40/100 |
| 62 | 81237 | Ohio City | CO | Zone 1 (High) | 40/100 |
| 63 | 81241 | Pitkin | CO | Zone 1 (High) | 40/100 |
| 64 | 81243 | Powderhorn | CO | Zone 1 (High) | 40/100 |
| 65 | 81248 | Sargents | CO | Zone 1 (High) | 40/100 |
| 66 | 81251 | Twin Lakes | CO | Zone 1 (High) | 40/100 |
| 67 | 81320 | Cahone | CO | Zone 1 (High) | 40/100 |
| 68 | 81325 | Egnar | CO | Zone 1 (High) | 40/100 |
| 69 | 81327 | Lewis | CO | Zone 1 (High) | 40/100 |
| 70 | 81329 | Marvel | CO | Zone 1 (High) | 40/100 |
| 71 | 81330 | Mesa Verde National Park | CO | Zone 1 (High) | 40/100 |
| 72 | 81331 | Pleasant View | CO | Zone 1 (High) | 40/100 |
| 73 | 81334 | Towaoc | CO | Zone 1 (High) | 40/100 |
| 74 | 81335 | Yellow Jacket | CO | Zone 1 (High) | 40/100 |
| 75 | 81411 | Bedrock | CO | Zone 1 (High) | 40/100 |
| 76 | 81414 | Cory | CO | Zone 1 (High) | 40/100 |
| 77 | 81420 | Lazear | CO | Zone 1 (High) | 40/100 |
| 78 | 81523 | Glade Park | CO | Zone 1 (High) | 40/100 |
| 79 | 81524 | Loma | CO | Zone 1 (High) | 40/100 |
| 80 | 81525 | Mack | CO | Zone 1 (High) | 40/100 |
| 81 | 81630 | De Beque | CO | Zone 1 (High) | 40/100 |
| 82 | 81636 | Battlement Mesa | CO | Zone 1 (High) | 40/100 |
| 83 | 81638 | Hamilton | CO | Zone 1 (High) | 40/100 |
| 84 | 81640 | Maybell | CO | Zone 1 (High) | 40/100 |
| 85 | 81646 | Molina | CO | Zone 1 (High) | 40/100 |
| 86 | 81432 | Ridgway | CO | Zone 1 (High) | 41/100 |
| 87 | 80439 | Evergreen | CO | Zone 1 (High) | 42/100 |
| 88 | 81089 | Walsenburg | CO | Zone 1 (High) | 44/100 |
| 89 | 80512 | Bellvue | CO | Zone 1 (High) | 45/100 |
| 90 | 80515 | Drake | CO | Zone 1 (High) | 45/100 |
| 91 | 80532 | Glen Haven | CO | Zone 1 (High) | 45/100 |
| 92 | 80645 | La Salle | CO | Zone 1 (High) | 45/100 |
| 93 | 80723 | Brush | CO | Zone 1 (High) | 45/100 |
| 94 | 80809 | Cascade | CO | Zone 1 (High) | 45/100 |
| 95 | 81023 | Beulah | CO | Zone 1 (High) | 45/100 |
| 96 | 81067 | Rocky Ford | CO | Zone 1 (High) | 45/100 |
| 97 | 81092 | Wiley | CO | Zone 1 (High) | 45/100 |
| 98 | 80818 | Genoa | CO | Zone 1 (High) | 46/100 |
| 99 | 81326 | Hesperus | CO | Zone 1 (High) | 46/100 |
| 100 | 81084 | Two Buttes | CO | Zone 1 (High) | 47/100 |
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: 2026-06-04.
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%.
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