R
RadonVerdict
EPA Zone Data 2026

Wisconsin Radon Map, Levels & Testing Guide

View EPA radon zone classifications for every county in Wisconsin. Open your county to compare basement test meaning, EPA action thresholds, and when mitigation pricing becomes worth checking.

28
Zone 1
High Risk
44
Zone 2
Moderate
0
Zone 3
Low Risk
Adams County Zone 2
Ashland County Zone 2
Barron County Zone 2
Bayfield County Zone 2
Brown County Zone 2
Buffalo County Zone 1
Burnett County Zone 2
Calumet County Zone 2
Chippewa County Zone 2
Clark County Zone 2
Columbia County Zone 2
Crawford County Zone 1
Dane County Zone 1
Dodge County Zone 1
Door County Zone 1
Douglas County Zone 2
Dunn County Zone 2
Eau Claire County Zone 2
Florence County Zone 2
Fond du Lac County Zone 1
Forest County Zone 2
Grant County Zone 1
Green County Zone 1
Green Lake County Zone 1
Iowa County Zone 1
Iron County Zone 2
Jackson County Zone 2
Jefferson County Zone 1
Juneau County Zone 2
Kenosha County Zone 2
Kewaunee County Zone 2
La Crosse County Zone 2
Lafayette County Zone 1
Langlade County Zone 1
Lincoln County Zone 2
Manitowoc County Zone 2
Marathon County Zone 1
Marinette County Zone 2
Marquette County Zone 2
Menominee County Zone 1
Milwaukee County Zone 2
Monroe County Zone 2
Oconto County Zone 2
Oneida County Zone 2
Outagamie County Zone 2
Ozaukee County Zone 2
Pepin County Zone 1
Pierce County Zone 1
Polk County Zone 2
Portage County Zone 1
Price County Zone 2
Racine County Zone 2
Richland County Zone 1
Rock County Zone 1
Rusk County Zone 2
Sauk County Zone 2
Sawyer County Zone 2
Shawano County Zone 1
Sheboygan County Zone 2
St. Croix County Zone 1
Taylor County Zone 2
Trempealeau County Zone 2
Vernon County Zone 1
Vilas County Zone 2
Walworth County Zone 1
Washburn County Zone 2
Washington County Zone 1
Waukesha County Zone 1
Waupaca County Zone 1
Waushara County Zone 2
Winnebago County Zone 2
Wood County Zone 1

Already tested? Get your itemized mitigation cost estimate.

View Wisconsin Mitigation Cost Estimates ->