Unlike mosquitoes, ticks don't have a clean on/off season. Understanding their year-round activity patterns helps you time protection correctly. Part of our Ultimate Tick Control Guide for Ontario Homeowners.
The Key Distinction: Two Tick Seasons in Ontario
Ontario's most dangerous tick — the blacklegged tick — has two distinct peak activity periods, driven by its lifecycle. This is why we recommend two professional tick treatments per season, not one.
Tiny nymphs (poppy-seed sized) emerge and quest aggressively. Responsible for majority of Lyme disease cases. Nearly impossible to see on skin.
Adult ticks emerge and aggressively seek large hosts. Larger and more visible than nymphs, but still easily missed. Active into late fall.
Month-by-Month Tick Activity in Ontario 2026
| Month | Blacklegged Tick | Dog Tick | What's Happening |
|---|---|---|---|
| January–March | Low* | Dormant | *Adults active on warm days (>4°C) |
| April | Moderate | Low | Nymphs begin emerging; adults still active |
| May | 🔴 HIGH | Moderate | Nymph peak begins — highest Lyme risk window |
| June | 🔴 HIGH | 🔴 HIGH | Nymph peak continues; dog ticks very active |
| July | Moderate | Moderate | Nymphs decline; larvae hatch |
| August | Moderate | Moderate | Larval tick activity; adults begin emerging |
| September | 🟠 HIGH | Moderate | Adult blacklegged tick peak; Lyme risk returns |
| October | 🟠 HIGH | Low | Adults very active before frost |
| November | Moderate | Dormant | Adults active until hard frost |
| December | Low | Dormant | Adults persist on warm days |
Why Two Treatments Cover Both Peak Windows
BuzzSkito's recommended two-treatment tick control program is deliberately timed to cover both peak risk periods:
- Treatment 1 — Late May / Early June: Targets nymphs as they emerge. Each treatment provides up to 30 days of residual protection, covering the entire nymph season through summer.
- Treatment 2 — Late August / September: Applied before the adult emergence peak, ensuring protection is active through the full fall tick season into November.
Together, these two treatments provide coverage from late May through November — the complete active tick season for Ontario's blacklegged tick population.
Frequently Asked Questions
Are ticks active in winter in Ontario?
Surprisingly, yes — blacklegged ticks remain active on days when temperatures exceed 4°C, even in winter. Unlike most Ontario insects, they don't die off in cold weather. This is why blacklegged ticks can be encountered on warm February or March days. American dog ticks and most other species do become dormant in winter.
What month has the most tick bites in Ontario?
May and June see the highest rate of Lyme disease transmission in Ontario due to the emergence of nymph ticks, which are tiny and difficult to detect. Adult tick activity peaks again in September and October. Both windows require vigilance and ideally professional yard treatment.
When should I get my first tick treatment of the season?
Late May is the optimal timing for your first professional tick treatment in the GTA — coinciding with the emergence of nymphs (the highest-risk life stage) before they become established in your yard. Your second treatment should be scheduled for late August or early September.