Out of 403 ZIP codes with data in Maine, these are mapped to counties in EPA Radon Zone 1. See also: National ZIP Codes in EPA Radon Zone 1 | All Maine Rankings
| Statistic | Value |
|---|---|
| ZIP codes ranked | 403 |
| Lowest value | Zone 1 (highest potential) |
| Median value | Zone 1 (highest potential) |
| State | Maine |
ZIP Codes in EPA Radon Zone 1
| Rank | ZIP Code | City | State | Radon Zone | Safety Score |
|---|---|---|---|---|---|
| 1 | 04730 | Houlton | ME | Zone 1 (highest potential) | 38/100 |
| 2 | 04901 | Waterville | ME | Zone 1 (highest potential) | 46/100 |
| 3 | 04021 | Cumberland Center | ME | Zone 1 (highest potential) | 47/100 |
| 4 | 04097 | North Yarmouth | ME | Zone 1 (highest potential) | 47/100 |
| 5 | 04096 | Yarmouth | ME | Zone 1 (highest potential) | 48/100 |
| 6 | 04252 | Lisbon Falls | ME | Zone 1 (highest potential) | 48/100 |
| 7 | 04989 | Vassalboro | ME | Zone 1 (highest potential) | 49/100 |
| 8 | 04073 | Sanford | ME | Zone 1 (highest potential) | 50/100 |
| 9 | 04083 | Springvale | ME | Zone 1 (highest potential) | 50/100 |
| 10 | 04074 | Scarborough | ME | Zone 1 (highest potential) | 60/100 |
| 11 | 04605 | Ellsworth | ME | Zone 1 (highest potential) | 60/100 |
| 12 | 04345 | Gardiner | ME | Zone 1 (highest potential) | 63/100 |
| 13 | 04401 | Bangor | ME | Zone 1 (highest potential) | 63/100 |
| 14 | 04062 | Windham | ME | Zone 1 (highest potential) | 64/100 |
| 15 | 04634 | Franklin | ME | Zone 1 (highest potential) | 64/100 |
| 16 | 03901 | Berwick | ME | Zone 1 (highest potential) | 65/100 |
| 17 | 04038 | Gorham | ME | Zone 1 (highest potential) | 65/100 |
| 18 | 04048 | Limerick | ME | Zone 1 (highest potential) | 65/100 |
| 19 | 04071 | Raymond | ME | Zone 1 (highest potential) | 65/100 |
| 20 | 04084 | Standish | ME | Zone 1 (highest potential) | 65/100 |
| 21 | 04085 | Steep Falls | ME | Zone 1 (highest potential) | 65/100 |
| 22 | 04092 | Westbrook | ME | Zone 1 (highest potential) | 65/100 |
| 23 | 04101 | Portland | ME | Zone 1 (highest potential) | 65/100 |
| 24 | 04102 | Portland | ME | Zone 1 (highest potential) | 65/100 |
| 25 | 04103 | Portland | ME | Zone 1 (highest potential) | 65/100 |
| 26 | 04105 | Falmouth | ME | Zone 1 (highest potential) | 65/100 |
| 27 | 04106 | South Portland | ME | Zone 1 (highest potential) | 65/100 |
| 28 | 04107 | Cape Elizabeth | ME | Zone 1 (highest potential) | 65/100 |
| 29 | 04210 | Auburn | ME | Zone 1 (highest potential) | 65/100 |
| 30 | 04428 | Eddington | ME | Zone 1 (highest potential) | 65/100 |
| 31 | 04429 | Holden | ME | Zone 1 (highest potential) | 65/100 |
| 32 | 04005 | Biddeford | ME | Zone 1 (highest potential) | 66/100 |
| 33 | 04043 | Kennebunk | ME | Zone 1 (highest potential) | 66/100 |
| 34 | 04049 | Limington | ME | Zone 1 (highest potential) | 66/100 |
| 35 | 04061 | North Waterboro | ME | Zone 1 (highest potential) | 66/100 |
| 36 | 04064 | Old Orchard Beach | ME | Zone 1 (highest potential) | 66/100 |
| 37 | 04072 | Saco | ME | Zone 1 (highest potential) | 66/100 |
| 38 | 04276 | Rumford | ME | Zone 1 (highest potential) | 66/100 |
| 39 | 04330 | Augusta | ME | Zone 1 (highest potential) | 66/100 |
| 40 | 04351 | Manchester | ME | Zone 1 (highest potential) | 66/100 |
| 41 | 04444 | Hampden | ME | Zone 1 (highest potential) | 66/100 |
| 42 | 04473 | Orono | ME | Zone 1 (highest potential) | 66/100 |
| 43 | 04736 | Caribou | ME | Zone 1 (highest potential) | 66/100 |
| 44 | 04769 | Presque Isle | ME | Zone 1 (highest potential) | 66/100 |
| 45 | 04785 | Van Buren | ME | Zone 1 (highest potential) | 66/100 |
| 46 | 03903 | Eliot | ME | Zone 1 (highest potential) | 67/100 |
| 47 | 03904 | Kittery | ME | Zone 1 (highest potential) | 67/100 |
| 48 | 03905 | Kittery Point | ME | Zone 1 (highest potential) | 67/100 |
| 49 | 03908 | South Berwick | ME | Zone 1 (highest potential) | 67/100 |
| 50 | 03909 | York | ME | Zone 1 (highest potential) | 67/100 |
| 51 | 04011 | Brunswick | ME | Zone 1 (highest potential) | 67/100 |
| 52 | 04240 | Lewiston | ME | Zone 1 (highest potential) | 67/100 |
| 53 | 04411 | Bradley | ME | Zone 1 (highest potential) | 67/100 |
| 54 | 04412 | Brewer | ME | Zone 1 (highest potential) | 67/100 |
| 55 | 04461 | Milford | ME | Zone 1 (highest potential) | 67/100 |
| 56 | 04462 | Millinocket | ME | Zone 1 (highest potential) | 67/100 |
| 57 | 04468 | Old Town | ME | Zone 1 (highest potential) | 67/100 |
| 58 | 04609 | Bar Harbor | ME | Zone 1 (highest potential) | 67/100 |
| 59 | 03902 | Cape Neddick | ME | Zone 1 (highest potential) | — |
| 60 | 03906 | North Berwick | ME | Zone 1 (highest potential) | — |
| 61 | 03907 | Ogunquit | ME | Zone 1 (highest potential) | — |
| 62 | 03911 | York Harbor | ME | Zone 1 (highest potential) | — |
| 63 | 04001 | Acton | ME | Zone 1 (highest potential) | — |
| 64 | 04002 | Alfred | ME | Zone 1 (highest potential) | — |
| 65 | 04003 | Bailey Island | ME | Zone 1 (highest potential) | — |
| 66 | 04006 | Biddeford Pool | ME | Zone 1 (highest potential) | — |
| 67 | 04009 | Bridgton | ME | Zone 1 (highest potential) | — |
| 68 | 04010 | Brownfield | ME | Zone 1 (highest potential) | — |
| 69 | 04015 | Casco | ME | Zone 1 (highest potential) | — |
| 70 | 04017 | Chebeague Island | ME | Zone 1 (highest potential) | — |
| 71 | 04019 | Cliff Island | ME | Zone 1 (highest potential) | — |
| 72 | 04020 | Cornish | ME | Zone 1 (highest potential) | — |
| 73 | 04022 | Denmark | ME | Zone 1 (highest potential) | — |
| 74 | 04024 | East Baldwin | ME | Zone 1 (highest potential) | — |
| 75 | 04027 | Lebanon | ME | Zone 1 (highest potential) | — |
| 76 | 04029 | Sebago | ME | Zone 1 (highest potential) | — |
| 77 | 04030 | East Waterboro | ME | Zone 1 (highest potential) | — |
| 78 | 04032 | Freeport | ME | Zone 1 (highest potential) | — |
| 79 | 04037 | Fryeburg | ME | Zone 1 (highest potential) | — |
| 80 | 04039 | Gray | ME | Zone 1 (highest potential) | — |
| 81 | 04040 | Harrison | ME | Zone 1 (highest potential) | — |
| 82 | 04041 | Hiram | ME | Zone 1 (highest potential) | — |
| 83 | 04042 | Hollis Center | ME | Zone 1 (highest potential) | — |
| 84 | 04046 | Kennebunkport | ME | Zone 1 (highest potential) | — |
| 85 | 04047 | Parsonsfield | ME | Zone 1 (highest potential) | — |
| 86 | 04050 | Long Island | ME | Zone 1 (highest potential) | — |
| 87 | 04051 | Lovell | ME | Zone 1 (highest potential) | — |
| 88 | 04055 | Naples | ME | Zone 1 (highest potential) | — |
| 89 | 04056 | Newfield | ME | Zone 1 (highest potential) | — |
| 90 | 04057 | North Bridgton | ME | Zone 1 (highest potential) | — |
Methodology
This ranking is limited to EPA county-level radon zone classification. Zone 1 is an EPA county-level radon-potential category; it does not measure a home or establish whether any building is above an action level. Within Zone 1, ZIP codes are sub-ranked by Home Safety Score to organize area context.
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: 2026-10-15.
Frequently Asked Questions
What is EPA Radon Zone 1?
Zone 1 is an EPA county-level radon-potential category. It is not a measurement for a home and cannot determine whether a building is above an action level. A home test is required for that decision.
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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