Huntsman spiders: big, fast, terrifying — and mostly harmless

No Australian spider generates more phone calls per gram of actual danger than the huntsman. It's huge, it's fast, it appears on lounge-room walls at 10pm — and it's one of the least dangerous spiders you'll ever share a house with. Here's the full picture, from what they are to what to actually do when one turns up above the TV.

Identifying a huntsman

Huntsmans are the flat, long-legged giants of Australian homes: grey to brown, often with mottled patterning, with legs that spread sideways in a crab-like stance rather than arching over the body. That sideways leg-set is the giveaway — it's what lets them slide into impossibly thin gaps under bark, behind picture frames and inside car mirrors. They don't build webs to catch prey; they're free-running hunters that chase down insects at speed.

How big do they get?

The common household species reach a legspan of 10–15cm — palm-of-your-hand territory — and the largest Australian species can exceed 20cm. The body itself is modest (2–4cm); it's the legs that deliver the fright. Females are generally larger and are the ones you'll find guarding a flat white egg sac behind bark or, occasionally, behind your wardrobe.

Why they come inside

Huntsmans follow food and shelter. They come indoors hunting the insects your lights attract, and they come in ahead of weather — a burst of huntsman sightings often precedes rain. Once inside, they favour flat hiding spots: behind frames and mirrors, curtain folds, the gap between wall and cupboard. In Melbourne they're most active through the warmer months, which is exactly when doors and windows stay open. One huntsman is a visitor. Regular huntsmans mean your house has the insect supply to sustain them — which is a treatable problem.

Are huntsmans dangerous?

Not meaningfully. Huntsmans are reluctant biters — their whole defence strategy is speed — and confirmed bites cause local pain and swelling comparable to a bee sting, with no serious medical consequences in healthy adults. There's no antivenom because none has ever been needed. The genuine risk a huntsman poses is indirect: the startle factor. People fall off chairs swatting them and, more seriously, panic when one emerges in a moving car. The spider itself is close to harmless — the genuinely dangerous Australian spiders are a much shorter list.

The huntsman in the car problem

Cars are prime huntsman real estate — mirror housings, door seals and vents are exactly the flat crevices they love, and a warm parked car is a comfortable refuge. If one appears while you're driving: it does not want to touch you, it wants a crack to hide in. Stay calm, pull over safely, open the doors and encourage it out with a piece of paper. Prevention: check mirror housings, don't leave windows down under trees overnight, and an occasional interior vacuum of door pockets and seals removes both spiders and the insects that attract them.

Getting one out (and keeping them out)

For the single visitor: the container-and-cardboard method works every time — place a container over the spider, slide card underneath, release it outside (they're genuinely useful pest controllers of cockroaches and moths). Don't spray a huntsman on a wall: a dying huntsman drops and runs erratically, which is how they end up down the back of the couch.

For regular visitors, treat the cause: seal door and window gaps, fit screens, switch outside lights to yellow LEDs that attract fewer insects, and knock down the insect population they're hunting. A professional spider treatment around entries, eaves and the perimeter cuts both the spiders and their food supply — it's the difference between the occasional wanderer and a weekly visitor. We treat homes and commercial sites across Melbourne, and huntsman call-outs peak exactly when the weather warms.

Frequently asked questions

Are huntsman spiders dangerous to humans?

No — bites are rare and cause only local pain and swelling. There's no antivenom because none has ever been needed. The main risk is the fright: people hurt themselves reacting, especially in cars.

How big can a huntsman spider get?

Common household huntsmans span 10–15cm across the legs; Australia's largest species can exceed 20cm. The body is only 2–4cm — the legspan does the intimidating.

Why do huntsman spiders come into the house?

They hunt the insects your home attracts, and they shelter ahead of bad weather. Flat hiding spots — behind frames, mirrors and furniture — are their preference. Frequent huntsmans usually mean a healthy indoor insect supply worth treating.

Should I kill a huntsman spider?

There's no need — they're effective predators of cockroaches and moths. The container-and-card relocation takes ten seconds. If you're seeing them constantly, treat the underlying insect population instead.

What do I do about a huntsman in my car?

Pull over safely, open the doors and shepherd it out with paper — it wants to escape, not touch you. They shelter in mirror housings and door seals, so check those if it keeps happening.

A1 Pest & Weed Control handles this for homes and businesses across Melbourne — licensed technicians, guaranteed results, and fast response: 0411 859 516 or get a free quote.