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Dangerous spiders: how to recognise them and stay safe

Most spiders are harmless and useful. A few have venom that can make people ill. Knowing their key markings and hiding places helps you avoid bites.

Widow spiders

Black widows and their relatives are glossy and round-bodied. Adult females are usually black with a red or orange hourglass under the abdomen. They build messy tangled webs in woodpiles, sheds, garages and outdoor furniture.

Recluse spiders

Brown recluse and related recluse spiders are brown with a darker violin-shaped mark on the back and six eyes in three pairs. They hide in closets, boxes, attics and stored clothing.

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Other spiders to treat with care

Funnel-web spiders in Australia and wandering spiders in South America are also dangerous. Large tarantulas usually have only mild venom, but their hairs can irritate skin and eyes.

How to avoid spider bites

Wear gloves when moving wood, rocks, boxes or garden waste.
Shake out shoes, clothes and towels left outside or in storage.
Keep beds away from walls and do not store items under beds.
Reduce clutter in garages, sheds and basements.

What to do after a spider bite

Wash the bite with soap and water and apply a cold pack. If possible, take a photo of the spider from a safe distance. Get medical help if pain spreads, muscles cramp, a wound grows or blisters, or the person feels unwell. For a child, or a suspected widow or recluse bite, contact a doctor or poison centre straight away.

⚠ Call emergency services straight away for trouble breathing, swelling of the face or throat, or a scorpion sting in a child. This page is general information, not medical advice.

Frequently asked questions

Are most spiders dangerous?

No. The vast majority of spiders cannot harm people and help by eating pests.

Should I kill a spider I think is dangerous?

Do not try to catch it by hand. Keep people and pets away and, if needed, call a pest professional.