Giant House Spider

The Giant House Spider (Eratigena atrica, formerly Tegenaria atrica) is one of the largest spiders found indoors in Europe and the Pacific Northwest of North America. It is closely related to the Hobo Spider and the two species are commonly mistaken for one another, but the Giant House Spider is bigger, faster and far more likely to actually turn up inside your home. This guide focuses on identification first: how to tell a Giant House Spider apart from the Hobo and from other large brown spiders, what to look for in its anatomy, and what its behaviour actually looks like up close.

Quick Identification: is this a Giant House Spider?

If you have a large brown spider sitting in a flat funnel-shaped web in the corner of a garage, shed or quiet room, run through this checklist. A Giant House Spider has all of the following features.

• Body length 12-18 mm for females, 10-14 mm for males. Leg span up to 75 mm. Distinctly larger than a Hobo Spider, which tops out at about 15 mm body and 40 mm leg span.
• Brown legs with subtle darker bands or chevrons. The bands are visible without magnification on adults. Hobo Spiders have solid brown legs with no banding.
• Strongly contrasting herringbone pattern on the upper abdomen. Sharper and more obvious than the Hobo Spider’s faint chevrons.
• Eight eyes in two close, parallel rows of four, as is typical of funnel weavers in the Agelenidae family.
• Flat, non-sticky funnel web with a small retreat tunnel at one corner. Often in attic eaves, behind furniture, in shed corners, or low against walls.
• Distinctly hairy legs and body. Hobo Spiders look smoother under the same magnification.

Giant House Spider anatomy

Cephalothorax

The cephalothorax is the front body section, fused from head and thorax. In Giant House Spiders it is roughly oval and a uniform mid to dark brown. Faint paler markings sometimes form a subtle pattern. Unlike the Brown Recluse, there is no violin-shaped mark. The cephalothorax houses the eight legs, the eight eyes, the pedipalps and the chelicerae.

Abdomen

The abdomen is the rear, oval body section. The most reliable identification feature on the abdomen is the herringbone pattern: a series of dark chevron or “V” shapes running down the upper midline. In Giant House Spiders these chevrons are bolder and more strongly contrasting than the muted version on a Hobo Spider, and they are visible at arm’s length without magnification.

Legs

The legs are long, hairy and brown, with subtle but visible darker bands or chevron markings. Leg I (the front pair) and Leg IV (the rear pair) are the longest. An adult female’s leg span can reach 75 mm, which is what gives the Giant House Spider its reputation as the largest indoor spider in many regions. The presence of leg banding is the single fastest way to separate a Giant House Spider from a Hobo Spider in the field: if the legs have visible darker rings, you are not looking at a Hobo.

Eyes and pedipalps

Giant House Spiders have eight small eyes arranged in two roughly parallel rows of four at the front of the cephalothorax, the standard funnel-weaver pattern. Adult males have noticeably enlarged pedipalps (the small leg-like appendages near the face) that look like small clubs or boxing gloves. Females have slim, simple pedipalps.

Where Giant House Spiders live

Giant House Spiders are native to Europe, where they have been the dominant indoor funnel-weaver for centuries. They were introduced to the Pacific Northwest of North America in the early 1900s and have since spread across British Columbia, Washington, Oregon and northern California. In some parts of this range they have actively displaced the Hobo Spider, both indoors and outdoors.

Indoors, you find them in quiet corners, behind furniture, in attic eaves, garages, sheds, basements, and the recesses of old stone or brick walls. Outdoors, they build webs in similar tucked-away spots: under loose bark, behind fence panels, in wood piles, against the foundations of houses. Their flat funnel webs are easy to recognise once you know the shape.

The most likely time of year to encounter a Giant House Spider in your home is autumn, when sexually mature males leave their webs and wander in search of females. This is the period when most “huge spider in the bath” stories happen across Britain and the Pacific Northwest.

Behaviour

Giant House Spiders are sit-and-wait ambush hunters. They build a flat funnel web with a tubular retreat at one corner, sit inside the retreat, and dash out when something walks across the sheet. Despite their imposing size they are non-aggressive and will retreat into their tunnel at the slightest disturbance.

When forced into the open they are extraordinarily fast. A Giant House Spider sprinting across a kitchen floor is one of the fastest spider movements you will ever see, with documented top speeds approaching half a metre per second. This running speed is one of the reasons they are so often mistaken for a more dangerous species: it is hard to assess subtle leg-banding while a spider is moving at full pace.

The Giant House Spider’s bite is medically insignificant to humans. They very rarely bite, even when handled, and on the occasions they do the result is comparable to a bee sting at most. There is no medical reason to fear them.

Giant House Spider vs Hobo Spider

These two species are the most commonly confused pair in the Pacific Northwest. They are closely related (both Eratigena) and superficially similar. The differences:

• Size: Giant House Spider 12-18 mm body, leg span up to 75 mm. Hobo Spider 8-15 mm body, leg span up to 40 mm.
• Legs: Giant House Spider has subtle dark bands. Hobo Spider has solid light brown legs with no banding.
• Abdomen pattern: Giant House Spider has bolder, higher-contrast chevrons. Hobo Spider has a muted herringbone.
• Habitat: Giant House Spider is the species you actually find living indoors. Hobo Spiders are far more often outdoors, around foundations and in gardens.
• Hairiness: Giant House Spider looks distinctly hairy on legs and body. Hobo Spider looks smoother.

If you are not sure which one you are looking at, try the spider identifier quiz at the top of the Hobo Spider page: five questions and it will tell you the most likely match.

Frequently asked questions

Related guides

• Hobo Spider identification guide with the interactive spider identifier quiz
• Spiders in North America: a guide to 3,000+ species
• Wolf Spider
• Brown Recluse Spider
• Venomous Spiders

 (2026, April 29). Giant House Spider. Animal Corner. Retrieved 2026, October 6, from https://animalcorner.org/animals/giant-house-spider/

. "Giant House Spider." Animal Corner, 2026, April 29, https://animalcorner.org/animals/giant-house-spider/.