Planning a hike, camping trip, or outdoor holiday in Europe? Tick activity varies dramatically between countries — what counts as "tick season" in Sweden looks nothing like tick season in Spain or Greece. This guide breaks down when ticks are active, what diseases they carry, and what to watch out for in 15 European countries.
How Tick Season Works in Europe
The castor bean tick (Ixodes ricinus) is the dominant species across most of Europe. It becomes active when ground temperatures exceed 7°C and humidity is high. But "tick season" is not one fixed window — it shifts by latitude, altitude, and local climate. Southern countries have longer seasons (sometimes year-round), while northern countries compress tick activity into spring and summer.
Climate change is extending tick season everywhere. Ticks are now found at higher altitudes and further north than a decade ago. The guidance below reflects current (2026) conditions.
Northern Europe
Sweden
Active season: April to October
Peak months: May to July
Key diseases: Lyme disease (borrelia), tick-borne encephalitis (TBE)
TBE vaccination: Recommended for outdoor activity in Stockholm archipelago, Sodermanland, and along the Baltic coast. Free or subsidized in many regions.
What to know: Ticks have spread north into Norrland in recent years. The Swedish Public Health Agency (Folkhalsomyndigheten) tracks TBE cases — over 500 reported annually. Roe deer and rodent populations drive tick abundance.
Norway
Active season: March to November (coastal areas), April to October (inland)
Peak months: May to August
Key diseases: Lyme disease, TBE (primarily southern coast)
What to know: Tick populations have expanded northward past Trondelag. Coastal areas from Agder to Vestland have the highest density. TBE risk is concentrated along the southern coast — vaccination recommended if hiking there regularly.
Finland
Active season: April to October
Peak months: May to July
Key diseases: Lyme disease, TBE (especially Aland Islands and southwestern archipelago)
What to know: TBE vaccination is provided free for residents of the Aland Islands. Mainland risk is lower but increasing. Tick density is highest in the southwestern coastal region.
Denmark
Active season: March to November
Peak months: May to July
Key diseases: Lyme disease (very common), TBE (Bornholm Island primarily)
What to know: Denmark has among the highest Lyme disease rates in Europe — up to 100 cases per 100,000 population in some areas. Bornholm Island is the main TBE hotspot. Ticks are widespread in forests, heathlands, and suburban gardens.
Central Europe
Germany
Active season: February to November
Peak months: April to July
Key diseases: Lyme disease (300,000+ estimated annual cases), TBE
TBE vaccination: Recommended by STIKO for residents and visitors to risk areas — primarily Bavaria, Baden-Wurttemberg, southern Thuringia, Saxony, and southern Hesse.
What to know: Germany has extensive TBE risk mapping (Robert Koch Institute). The number of designated risk districts has expanded every year. Mild winters mean ticks can be active as early as February. Germany has more reported tick-borne disease cases than any other EU country.
Austria
Active season: March to November
Peak months: April to July
Key diseases: TBE (nationwide risk), Lyme disease
TBE vaccination: Included in the national vaccination schedule. Austria has one of the highest TBE vaccination rates in Europe (over 80%).
What to know: Austria is considered entirely a TBE risk area below 1,500 meters altitude. TBE vaccination is standard, not optional. Ticks are found from lowland meadows up to alpine pastures. Despite high vaccination rates, 50-100+ TBE cases still occur annually.
Switzerland
Active season: March to November
Peak months: April to July
Key diseases: TBE, Lyme disease
TBE vaccination: Recommended for all areas except Geneva and Ticino.
What to know: Tick activity reaches up to 1,500 meters altitude and climbing. The Federal Office of Public Health maintains a detailed TBE risk map. Check specific canton-level guidance before hiking.
Netherlands
Active season: March to October
Peak months: April to July
Key diseases: Lyme disease (high prevalence)
What to know: No TBE risk, but Lyme disease rates are among the highest in Europe. RIVM (Dutch public health institute) estimates 27,000 GP consultations for tick bites annually. The Veluwe, dune areas, and forests in Gelderland and Noord-Brabant are highest risk. The "Tekenradar" citizen science project tracks tick activity in real time.
Belgium
Active season: March to October
Peak months: May to July
Key diseases: Lyme disease
What to know: Wallonia and the Ardennes have the highest tick density. No significant TBE risk. Lyme disease is a notifiable condition — around 10,000-15,000 cases estimated annually.
Western Europe
France
Active season: March to November
Peak months: April to June, September to October (bimodal pattern)
Key diseases: Lyme disease (most common tick-borne disease), TBE (Alsace region)
What to know: France has a distinct bimodal tick season — activity dips during the hot, dry summer months (July-August) and picks up again in autumn. Alsace-Lorraine has isolated TBE risk. The national "Citique" citizen science program tracks tick bites. Estimated 50,000+ Lyme cases annually.
United Kingdom
Active season: March to October
Peak months: April to July
Key diseases: Lyme disease (2,000-3,000 confirmed cases annually, likely underreported)
What to know: No TBE risk. Highest tick density in the Scottish Highlands, New Forest, Exmoor, South Downs, and Lake District. Tick populations have increased significantly — PHE data shows Lyme diagnoses doubling over the past decade. Deer population growth is a major driver.
Ireland
Active season: March to October
Peak months: May to August
Key diseases: Lyme disease
What to know: No TBE risk. Tick activity is widespread in heathland, rough grassland, and forest edges. Wicklow Mountains, West Cork, and Connemara are notable tick areas. Lyme disease awareness has increased but many cases still go undiagnosed.
Southern Europe
Spain
Active season: Year-round in mild coastal areas; March to November inland
Peak months: April to June (spring), September to October (autumn)
Key diseases: Crimean-Congo hemorrhagic fever (CCHF — carried by Hyalomma ticks), Lyme disease (northern regions)
What to know: Spain has a unique risk profile. Hyalomma marginatum ticks in central and southern Spain can transmit CCHF — fatal cases have been recorded since 2016. Hot, dry summers reduce Ixodes activity but Hyalomma species tolerate heat better. Northern green Spain (Basque Country, Asturias, Galicia) has a more typical European tick season with Lyme risk.
Italy
Active season: March to November (north), year-round possible in the south
Peak months: April to June
Key diseases: TBE (northeastern regions — Friuli Venezia Giulia, Trentino-Alto Adige, Veneto), Lyme disease
What to know: TBE risk is concentrated in the northeastern alpine and pre-alpine regions. Vaccination recommended for hikers in Trentino and Friuli. Mediterranean coastal areas have lower tick density but are not tick-free. The Italian National Health Institute (ISS) monitors tick-borne diseases.
Greece
Active season: March to November
Peak months: April to June
Key diseases: CCHF (northern border regions), Lyme disease (low risk)
What to know: Mainland northern Greece (near Bulgarian and Turkish borders) has Hyalomma ticks carrying CCHF. Islands and southern coastal areas have lower tick density. Hot dry summers suppress activity. Hikers in Macedonia and Thrace should take extra precautions.
Eastern Europe
Poland
Active season: March to November
Peak months: May to July
Key diseases: Lyme disease (very high — 20,000+ cases annually), TBE (northeastern regions)
What to know: Poland has among the highest Lyme disease incidence rates in Europe. TBE risk is highest in Podlasie, Warmia-Masuria, and the Bieszczady Mountains. TBE vaccination recommended for residents and visitors to northeastern voivodeships. Bialowieza Forest visitors should be especially vigilant.
Quick Reference Table
| Country | Season Start | Peak | Season End | TBE Risk | Key Disease |
|---|---|---|---|---|---|
| Sweden | April | May-Jul | October | Yes (coastal) | Lyme, TBE |
| Norway | March | May-Aug | November | Low (south coast) | Lyme |
| Finland | April | May-Jul | October | Yes (Aland, SW coast) | Lyme, TBE |
| Denmark | March | May-Jul | November | Low (Bornholm) | Lyme |
| Germany | February | Apr-Jul | November | Yes (south) | Lyme, TBE |
| Austria | March | Apr-Jul | November | Yes (nationwide) | TBE, Lyme |
| Switzerland | March | Apr-Jul | November | Yes (most cantons) | TBE, Lyme |
| Netherlands | March | Apr-Jul | October | No | Lyme |
| Belgium | March | May-Jul | October | No | Lyme |
| France | March | Apr-Jun, Sep-Oct | November | Low (Alsace) | Lyme |
| United Kingdom | March | Apr-Jul | October | No | Lyme |
| Ireland | March | May-Aug | October | No | Lyme |
| Spain | Year-round* | Apr-Jun | Year-round* | No | CCHF, Lyme |
| Italy | March | Apr-Jun | November | Yes (northeast) | TBE, Lyme |
| Greece | March | Apr-Jun | November | No | CCHF (north) |
| Poland | March | May-Jul | November | Yes (northeast) | Lyme, TBE |
* In mild coastal areas of southern Spain, ticks can be active year-round.
How to Stay Protected — Regardless of Country
The prevention basics are the same everywhere in Europe:
- Cover exposed skin — ticks crawl upward from ground level. Ankles, calves, and legs are the primary entry points. Wear long trousers tucked into socks, and consider a mesh insect suit for high-density areas.
- Do a thorough tick check after every outdoor activity — especially behind the knees, groin, armpits, hairline, and behind the ears.
- Remove ticks within 24 hours — Lyme transmission typically requires 24-36 hours of attachment. Use fine-pointed tweezers or a tick removal tool. Grasp as close to the skin as possible, pull steadily upward.
- Get vaccinated for TBE if visiting a risk area (see table above). TBE is transmitted within minutes of a bite — there is no grace period like with Lyme. Vaccination is the only reliable protection.
- Stick to marked trails where possible. Ticks wait on grass, bracken, and low vegetation — not in trees.
Heading outdoors in Europe this season? The Tix Hiker's Bug Defense Kit gives you full-body mesh protection against ticks, mosquitoes, and biting insects — no chemicals, no reapplication, no expiry date.