Ticks in Iowa

Ticks are active in Iowa whenever the ground is not frozen, led by the Lyme-carrying deer tick. TickZone scores all 940 Iowa towns every morning, so risk stays local: pick your town for today's number, a 7-day outlook, and what's driving it.

Tick season in Iowa

Tick season in Iowa runs whenever the ground is not frozen, roughly March through November, with two peaks. Nymph deer ticks, the poppy-seed-sized stage that causes most Lyme cases, peak from late May through July. Adult deer ticks make a second push in October and November, and on any winter day above about 40 F they can quest again. American dog ticks are busiest from April through July.

Generalized for the Northeast and Upper Midwest Lyme belt.
Life stageJFMAMJJASOND
Deer tick nymphs
Deer tick adults
American dog tick
Lone star tick
Peak Active
Generalized for the Northeast and Upper Midwest Lyme belt. Activity windows by life stage from TickEncounter (Univ. of Rhode Island) and the Northeast Regional Center for Excellence in Vector-Borne Diseases. Any warm spell can wake ticks earlier than the calendar suggests.

Those are averages, and any single week can run hotter or colder than the calendar suggests. The daily score on every town page folds the season, the weather, and local habitat into one number each morning, so it is the safer way to time yard work, hikes, and pet prevention.

Highest-risk towns in Iowa (2026)

Iowa's highest-risk towns are spread across several counties, led by Clayton. The top 10 towns run 60 to 97 percent forest, ranked at peak season so the list stays stable.

  1. 1Westwood Henry CountyModerate at peak
  2. 2Keomah Village Mahaska CountyModerate at peak
  3. 3University Heights Johnson CountyModerate at peak
  4. 4McGregor Clayton CountyModerate at peak
  5. 5Fraser Boone CountyModerate at peak
  6. 6Panorama Park Scott CountyModerate at peak
  7. 7Clayton Clayton CountyModerate at peak
  8. 8Sageville Dubuque CountyModerate at peak
  9. 9North Buena Vista Clayton CountyModerate at peak
  10. 10Windsor Heights Polk CountyModerate at peak

See the riskiest towns in every state →

All Iowa towns, by county

Adair County · 5 towns

Adams County · 4 towns

Allamakee County · 6 towns

Appanoose County · 11 towns

Audubon County · 5 towns

Benton County · 14 towns

Black Hawk County · 9 towns

Boone County · 9 towns

Bremer County · 8 towns

Buchanan County · 11 towns

Buena Vista County · 10 towns

Butler County · 10 towns

Calhoun County · 11 towns

Carroll County · 13 towns

Cass County · 8 towns

Cedar County · 8 towns

Cerro Gordo County · 10 towns

Cherokee County · 8 towns

Chickasaw County · 8 towns

Clarke County · 3 towns

Clay County · 10 towns

Clayton County · 16 towns

Clinton County · 14 towns

Crawford County · 13 towns

Dallas County · 14 towns · 8/100k Lyme

Davis County · 4 towns

Decatur County · 10 towns

Delaware County · 11 towns · 28/100k Lyme

Des Moines County · 5 towns

Dickinson County · 10 towns

Dubuque County · 21 towns · 22/100k Lyme

Emmet County · 6 towns

Fayette County · 13 towns

Floyd County · 7 towns

Franklin County · 8 towns

Fremont County · 8 towns

Greene County · 7 towns

Grundy County · 9 towns

Guthrie County · 9 towns

Hamilton County · 9 towns

Hancock County · 8 towns

Hardin County · 12 towns

Harrison County · 10 towns

Henry County · 9 towns

Howard County · 5 towns

Humboldt County · 11 towns

Ida County · 5 towns

Iowa County · 7 towns · 49/100k Lyme

Jackson County · 12 towns

Jasper County · 13 towns

Jefferson County · 7 towns

Johnson County · 11 towns · 21/100k Lyme

Jones County · 8 towns

Keokuk County · 16 towns

Kossuth County · 12 towns

Lee County · 8 towns

Linn County · 17 towns · 11/100k Lyme

Louisa County · 9 towns

Lucas County · 5 towns

Lyon County · 8 towns

Madison County · 8 towns

Mahaska County · 9 towns

Marion County · 9 towns

Marshall County · 13 towns

Mills County · 7 towns

Mitchell County · 8 towns

Monona County · 10 towns

Monroe County · 3 towns

Montgomery County · 6 towns

Muscatine County · 8 towns

O'Brien County · 8 towns

Osceola County · 5 towns

Page County · 10 towns

Palo Alto County · 9 towns

Plymouth County · 11 towns

Pocahontas County · 8 towns

Polk County · 17 towns · 3/100k Lyme

Pottawattamie County · 14 towns

Poweshiek County · 8 towns

Ringgold County · 9 towns

Sac County · 9 towns

Scott County · 16 towns · 5/100k Lyme

Shelby County · 11 towns

Sioux County · 13 towns

Story County · 14 towns · 5/100k Lyme

Tama County · 12 towns

Taylor County · 8 towns

Union County · 7 towns

Van Buren County · 7 towns

Wapello County · 7 towns

Warren County · 13 towns

Washington County · 9 towns

Wayne County · 8 towns

Webster County · 13 towns

Winnebago County · 7 towns

Winneshiek County · 8 towns

Woodbury County · 15 towns

Worth County · 7 towns

Wright County · 8 towns

Iowa tick questions

Are there ticks in Iowa?
Yes. Iowa has ticks in every county, led by the deer tick (blacklegged tick) that spreads Lyme disease, along with the American dog tick and the lone star tick. They are active whenever the ground is not frozen, and today 131 of the state's 940 towns are at moderate or high tick risk on TickZone's daily score.
What types of ticks live in Iowa?
Iowa has the deer tick (blacklegged tick), which carries Lyme disease; the American dog tick; and the lone star tick, which is reported in the state and causes alpha-gal syndrome. See the Iowa tick identification chart for photos and how to tell them apart.
When does tick season start and end in Iowa?
In Iowa, ticks are active whenever the ground is not frozen, roughly March through November. Nymph deer ticks peak in June and July and cause most Lyme cases, and adult ticks have a second peak in the fall. On any winter day above freezing, adult ticks can still bite.
When is flea and tick season?
Flea and tick season generally runs from early spring through late fall, peaking in the warm summer months. In Iowa, start prevention for pets and people in March and keep it up through November, since ticks can bite on any mild day.
Which tick carries Lyme disease in Iowa?
The deer tick, also called the blacklegged tick, is the tick that spreads Lyme disease in Iowa. The American dog tick and lone star tick do not carry Lyme.