Best Time to See Ticks in Illinois
May, April and June is the best time to see ticks in Illinois. Based on 2,504 verified iNaturalist observations, here is exactly when ticks are most active across the year in Illinois.
By Tim, founder of Easy Street Markets. I maintain the wildlife database and verify every animal and source myself. Updated July 22, 2026.
American Dog Tick · Nova Patch CC BY-SA
American Dog Tick · Matthew Lindsey CC BY
Asian Longhorned Tick · Zachary Dankowicz CC BY
2,504 verified observations of ticks in Illinois, recorded across 12 months of the year on iNaturalist.
When ticks are recorded in Illinois
Peak month
May
710 records (28.4% of the year)
| Month | Observations | Share |
|---|---|---|
| January | 7 | 0.3% |
| February | 21 | 0.8% |
| March | 107 | 4.3% |
| Aprilpeak | 595 | 23.8% |
| Maypeak | 710 | 28.4% |
| Junepeak | 511 | 20.4% |
| July | 347 | 13.9% |
| August | 59 | 2.4% |
| September | 21 | 0.8% |
| October | 65 | 2.6% |
| November | 48 | 1.9% |
| December | 13 | 0.5% |
Ticks you are most likely to see
| Species | Verified observations |
|---|---|
| American Dog Tick | 1,459 |
| Lone Star Tick | 423 |
| Eastern Black-legged Tick | 370 |
| Gulf Coast Tick | 61 |
| Rabbit Tick | 6 |
| Softbacked Ticks | 1 |
Weather to expect, source Open-Meteo
Typical weather in Illinois
Recent typical conditions by month, so you can plan a trip around both when ticks are active and what the weather is doing. The best months to look for ticks sit around 43 to 83 degrees Fahrenheit, so pack for that.
| Month | Avg high | Avg low | Rain |
|---|---|---|---|
| Jan | 38°F | 23°F | 3" |
| Feb | 40°F | 22°F | 3.1" |
| Mar | 53°F | 34°F | 4.8" |
| Aprbest time | 63°F | 43°F | 4.1" |
| Maybest time | 73°F | 54°F | 4.6" |
| Junbest time | 83°F | 64°F | 3.5" |
| Jul | 85°F | 68°F | 4.3" |
| Aug | 83°F | 66°F | 3.9" |
| Sep | 79°F | 61°F | 3" |
| Oct | 65°F | 48°F | 4.9" |
| Nov | 52°F | 35°F | 1.8" |
| Dec | 45°F | 29°F | 2.3" |
Typical recent conditions (5-year means) from the Open-Meteo archive, averaged for Illinois. Weather varies year to year, so treat these as a guide.
Sightings of ticks in Illinois peak in May, when 710 of the year's 2,504 verified observations are logged — about 28.4% of the annual total. Activity stays high through May, April and June.
The quietest stretch is January, when ticks are hardest to find — January sees just 7 records. If a reliable sighting matters, plan around the peak window rather than the off-season.
The ticks you are most likely to encounter in Illinois are American Dog Tick, Lone Star Tick and Eastern Black-legged Tick — the most-recorded species in the state. Each keeps its own seasonal rhythm, but the month-by-month pattern above reflects every reported sighting together.
Where to go
Best places to see ticks in Illinois
- Lewis & Clark National Historic Trail — National Historic Trail
- Lincoln Home National Historic Site — National Historic Site
- Emmett Till and Mamie Till-Mobley National Monument — National Monument
- Mormon Pioneer National Historic Trail — National Historic Trail
- New Philadelphia National Historic Site — National Historic Site
- Pullman National Historical Park — National Historical Park
Frequently asked questions
What is the best month to see ticks in Illinois?+
May is the single best month, and the broader peak window runs through May, April and June, based on 2,504 verified iNaturalist observations.
When are ticks hardest to see in Illinois?+
January is the quietest month for ticks in Illinois, with only 7 verified records.
Are ticks active year-round in Illinois?+
Ticks are recorded in 12 of 12 months in Illinois, so they can be seen year-round, with a clear peak in May.
More places to see ticks
More wildlife in Illinois