Reviewed by William "Willy" Vizcarrondo, NYS DEC Certified Commercial Pesticide Applicator C1825832. Updated September 23, 2026.
The spiders in a Long Island house are mostly cellar spiders, common house spiders, wolf spiders and jumping spiders. They live indoors year round, they're there because there are insects to eat, and the fangs of almost all of them are too small to break an adult's skin.
| Size | Body from 1/8 inch (cobweb and cellar spiders) to about 1 inch (large wolf spiders), legs much longer |
|---|---|
| Color | Tan, gray, brown or mottled; jumping spiders often black with white or colored marks |
| Look-alikes | Daddy longlegs (harvestmen, one body segment, not spiders); house centipedes (many legs, fast) |
| Where you'll find it | Basement and garage corners, window frames, behind furniture, closets, crawlspaces, under decks |
| Active on Long Island | Year round indoors; most sightings August through October when males wander |
| Danger level | Almost none; most house spiders can't bite through adult skin, and bites of any kind are rare |
House spiders are in Long Island homes all year, but calls spike in late summer and early fall, when mature males leave their webs to wander and people start seeing them on walls and in tubs.
Cellar spiders are the long-legged, pale ones hanging upside down in loose, messy webs in basement corners; they shake the web when disturbed. Common house spiders are small, tan to gray, with a round abdomen, and build the cobwebs in room corners and around windows. Wolf spiders are bigger, brown and hairy, with no web; they hunt on the ground and are the ones that run across a basement floor or garage. Jumping spiders are small and compact, often black with white marks, move in short hops, and are out in daylight on window sills and walls.
Two things that are not house spiders: daddy longlegs, which have one round body segment and are harvestmen, not spiders; and house centipedes, which have many long legs, move fast, and are a moisture sign, not a spider problem. Bites from the spiders that live in Long Island homes are rare and almost never serious.
House spiders don't spread disease, don't damage the house, and almost never bite. UC IPM notes that the jaws of most spiders are so small the fangs can't penetrate an adult's skin, and the Burke Museum's arachnology staff put it plainly: spiders very rarely bite humans, there is no evidence of spiders biting people in their sleep, and nearly all unexplained skin bumps and sores blamed on spiders have other causes. What a spider population does tell you is that the house has a food supply. UC IPM's rule is that the more insects there are inside a building, the more likely it is to have spiders, so a lot of spiders in a basement usually means moisture, silverfish, centipedes or other prey, and that's the problem worth solving.
Yes, for most people. Vacuum the webs, egg sacs and spiders; UC IPM notes a spider's soft body usually doesn't survive the vacuum. Cut the clutter in the basement and garage, tape storage boxes shut, sticky traps along baseboards and behind furniture catch the wanderers, and switching outdoor lights to yellow bulbs cuts the insects that draw spiders to the house. Sprays are of limited value, since a spider walking over a treated surface on the tips of its legs picks up very little, and UC IPM points out it's easier and less toxic to crush or vacuum the spider than to spray it.
Call us when the spiders are a symptom. If a basement or crawlspace has a lot of them, there's a moisture problem and an insect population feeding them, and that's what the general insect treatment is for.
We treat the insects the spiders are eating and the conditions that bring them: sealing gaps at the foundation and utility lines, crack-and-void treatment in the basement and garage, and a plain answer about whether it's a moisture problem. Spiders are covered under general insect treatment, which is quoted in writing with no guarantee, because they come in from outside all season.
Related answers
Not the ones in your house. The spiders in Long Island homes are cellar spiders, house spiders, wolf spiders and jumping spiders, and UC IPM notes the fangs of most spiders are too small to break an adult's skin. The Burke Museum's arachnologists put it plainly: spiders very rarely bite humans.
Because mature male spiders leave their webs in late summer to look for mates, so the spiders that have been in the house all year suddenly show up on walls and in tubs. They didn't come in from outside; the Burke Museum notes outdoor spiders don't move indoors in fall, and house spiders are separate species that live inside year round.
Almost certainly not. The Burke Museum's arachnologists note there is no evidence of spiders biting people in their sleep, and nearly all mystery bumps and sores blamed on spiders turn out to have other causes. If you're getting bitten at night on Long Island, bed bugs and mosquitoes are far more likely.
Not for long. Spiders walk on the tips of their legs and pick up little from a treated surface, and a spray does nothing about the insects they're eating. Vacuuming, cutting clutter, sticky traps and getting the moisture and prey insects under control work better, and that's what our general insect treatment covers.
Think you have spiders? Call (516) 509-6001 for a free written quote.