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Tick season, state by state

Ticks wake earlier and stay later than fleas — many start questing at about 40°F. This map colors each state by how much of the year ticks stay active there; click through for the calendar and the local species.

Alabama — tick season year-round Alaska — tick season mid-April to mid-October Arizona — tick season year-round Arkansas — tick season year-round California — tick season year-round Colorado — tick season late February to late November Connecticut — tick season mid-March to early December Delaware — tick season mid-February to mid-December Florida — tick season year-round Georgia — tick season year-round Hawaii — tick season year-round Idaho — tick season early March to mid-November Illinois — tick season early March to late November Indiana — tick season early March to early December Iowa — tick season mid-March to mid-November Kansas — tick season mid-February to early December Kentucky — tick season early February to mid-December Louisiana — tick season year-round Maine — tick season early April to mid-November Maryland — tick season mid-February to late December Massachusetts — tick season mid-March to late November Michigan — tick season late March to mid-November Minnesota — tick season late March to early November Mississippi — tick season year-round Missouri — tick season mid-February to early December Montana — tick season late March to early November Nebraska — tick season early March to mid-November Nevada — tick season late January to mid-December New Hampshire — tick season late March to late November New Jersey — tick season late February to mid-December New Mexico — tick season late January to mid-December New York — tick season mid-March to early December North Carolina — tick season year-round North Dakota — tick season early April to early November Ohio — tick season early March to early December Oklahoma — tick season nearly year-round, with a brief midwinter lull Oregon — tick season year-round Pennsylvania — tick season early March to early December Rhode Island — tick season mid-March to early December South Carolina — tick season year-round South Dakota — tick season late March to early November Tennessee — tick season year-round Texas — tick season year-round Utah — tick season mid-February to late November Vermont — tick season early April to mid-November Virginia — tick season year-round Washington — tick season mid-February to late November West Virginia — tick season mid-February to mid-December Wisconsin — tick season late March to mid-November Wyoming — tick season late March to early November
4 months or fewer 5–6 months 7–8 months 9–11 months Essentially year-round

Every state's tick calendar

Fleas run warmer and later — see flea season by state.

Frequently asked questions

When does tick season start?

Earlier than most people think. Many ticks begin questing once temperatures clear roughly 40°F — weeks before flea season — and adult blacklegged ticks will hunt on any mild midwinter day. In much of the South, tick activity never truly stops.

Which ticks should dog owners actually worry about?

It depends on the state: blacklegged (deer) ticks carry Lyme in the East and upper Midwest, lone star ticks dominate the Southeast, American dog ticks are widespread east of the Rockies, Rocky Mountain wood ticks take over in the intermountain West, and brown dog ticks thrive in hot climates — indoors included. Each state page lists the species that matter there.

Do ticks die off in winter?

Mostly they pause. Snow and leaf litter insulate them nicely, and adult blacklegged ticks resume hunting whenever a winter day turns mild. That's why the tick calendar rarely drops to zero — and why vets recommend keeping dogs on tick prevention through the cold months too.

How are these tick season windows estimated?

From NOAA U.S. Climate Normals (1991–2020) near each state's major cities, crossed with the ~40°F activity threshold reported in published tick research. They're climate-based estimates of outdoor pressure; individual years and microclimates vary.