FleaDates › Tick season › Idaho
Mountain West · ID
When are ticks active in Idaho?
Ticks in Idaho are typically active early March to mid-November, heaviest May–Sep — and one warm spell can wake them well ahead of spring.
Ticks to know in Idaho
The Rocky Mountain wood tick is the species that matters most in Idaho, out across the southern sagebrush and canyon country and along forest edges up in the panhandle, with American dog ticks common in grassy margins statewide and brown dog ticks capable of setting up in a kennel or heated garage. Ticks are already out at a low level in March and remain a factor into November, with the heaviest stretch from June through September. Spring walks along creek bottoms are prime pickup ground — tall grass, questing ticks — and a comb-through back at the truck saves trouble later.
Wherever the calendar sits this month, the habit that actually catches ticks is the after-walk check: ears, collar line, armpits, between the toes. Prevention plus checks beats either alone.
Month-by-month tick activity in Idaho
| Month | Typical activity | Average temperature |
|---|---|---|
| January | Quiet | 29.7°F |
| February | Low | 33.6°F |
| March | Moderate | 41.3°F |
| April | Moderate | 47.7°F |
| May | High | 56.4°F |
| June | Peak | 63.8°F |
| July | Peak | 72.7°F |
| August | Peak | 71.5°F |
| September | Peak | 62.3°F |
| October | Moderate | 49.6°F |
| November | Low | 37.7°F |
| December | Quiet | 29.7°F |
Estimates from NOAA U.S. Climate Normals (1991–2020), averaged across 3 weather stations near Idaho's larger cities, using the ~40°F activity threshold reported in published tick research. Real years run early or late with the weather.
Fleas peak later. Idaho flea season typically runs mid-April to late October — see the Idaho flea season page.
Frequently asked questions
When does tick season start in Idaho?
Around early March in a typical year, once temperatures clear roughly 40°F — noticeably earlier than flea season. A February thaw can bring ticks out ahead of schedule.
What ticks live in Idaho?
The species dog owners most often meet in Idaho: Rocky Mountain wood tick, American dog tick, brown dog tick. The Rocky Mountain wood tick is the species that matters most in Idaho, out across the southern sagebrush and canyon country and along forest edges up in the panhandle, with American dog ticks common in grassy margins statewide and brown dog ticks capable of setting up in a kennel or heated garage. Ticks are already out at a low level in March and remain a factor into November, with the heaviest stretch from June through September. Spring walks along creek bottoms are prime pickup ground — tall grass, questing ticks — and a comb-through back at the truck saves trouble later.
Do I need tick prevention in winter in Idaho?
Yes. Ticks overwinter under leaf litter and snow rather than dying off, and mild spells wake them — which is why veterinary organizations recommend year-round parasite prevention. The calendar shows when pressure peaks, not when protection can lapse.
What about fleas in Idaho?
Fleas run on a warmer calendar — in Idaho that's mid-April to late October. See the Idaho flea season page for that month-by-month picture.