Wolf Spider vs House Spider: How to Tell Them Apart

Two of the spiders people meet most often indoors are the wolf spider and the common house spider — and they could hardly be more different once you know what to look at. One is a fast ground hunter, the other a patient web-sitter.

At a glance

Feature	Wolf Spider	House Spider
Build	Stocky, hairy, robust	Slender, delicate
Size	Large (up to 35 mm body)	Small (5–8 mm body)
Web	None — actively hunts	Tangled cobweb
Behaviour	Runs fast across the floor	Hangs in its web
Eyes	Two large forward eyes that shine	Eight small, even eyes

The behaviour test

The quickest separator is what the spider is doing. A wolf spider is almost always on the move — sprinting across a floor or wall, never sitting in a web, because it chases prey down. A house spider is the opposite: it sits quietly, often upside-down, in a messy cobweb spun into a corner.

The eye-shine trick

Wolf spiders have a reflective layer in their eyes. Shine a torch at one in the dark and you will catch a distinct greenish eye-shine — something a house spider will not give you. It is a favourite field trick for spotting them on a lawn at night.

Size and body

Wolf spiders are noticeably bigger and hairy, with thick, powerful legs built for running. House spiders are small and fine-limbed, with a rounder, smoother abdomen. A wolf spider mother is unmistakable when she is carrying her egg sac attached to her spinnerets, or her spiderlings riding on her back.

Are either dangerous?

Neither is a serious threat. A wolf spider can deliver a defensive nip if cornered — comparable to a bee sting and nothing more for most people — while the common house spider is entirely harmless. Both are, in fact, useful housemates that quietly reduce the insect population indoors.

When you are unsure, photograph the spider and let an identifier weigh the cues together — body bulk, leg thickness, eye layout and whether there is a web — to confirm which of the two you are looking at.