FleaDates › Tick season › Montana
Mountain West · MT
When are ticks active in Montana?
Ticks in Montana are typically active late March to early November, heaviest May–Sep — and one warm spell can wake them well ahead of spring.
Ticks to know in Montana
Montana's signature tick is the Rocky Mountain wood tick, out and questing from the first bare-ground weeks of spring, with American dog ticks sharing the same cover. Pressure ramps up through May and June, tops out in July and August, and eases off through October. Wood ticks favor animal trails and the edges of open meadows, so a dog that ranges ahead on foothill hikes comes back with the most — and a tick still crawling is far easier to deal with than one already attached.
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 Montana
| Month | Typical activity | Average temperature |
|---|---|---|
| January | Quiet | 25.7°F |
| February | Quiet | 28.2°F |
| March | Low | 36.5°F |
| April | Moderate | 44.1°F |
| May | High | 53.3°F |
| June | High | 61.3°F |
| July | Peak | 69.9°F |
| August | Peak | 68.5°F |
| September | High | 58.7°F |
| October | Moderate | 45.6°F |
| November | Low | 34°F |
| December | Quiet | 26°F |
Estimates from NOAA U.S. Climate Normals (1991–2020), averaged across 3 weather stations near Montana'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. Montana flea season typically runs late April to mid-October — see the Montana flea season page.
Frequently asked questions
When does tick season start in Montana?
Around late 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 Montana?
The species dog owners most often meet in Montana: Rocky Mountain wood tick, American dog tick, brown dog tick. Montana's signature tick is the Rocky Mountain wood tick, out and questing from the first bare-ground weeks of spring, with American dog ticks sharing the same cover. Pressure ramps up through May and June, tops out in July and August, and eases off through October. Wood ticks favor animal trails and the edges of open meadows, so a dog that ranges ahead on foothill hikes comes back with the most — and a tick still crawling is far easier to deal with than one already attached.
Do I need tick prevention in winter in Montana?
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 Montana?
Fleas run on a warmer calendar — in Montana that's late April to mid-October. See the Montana flea season page for that month-by-month picture.