Where Do Spiders Go in Winter? Why You See More Indoors in Autumn
Most spiders spend winter outdoors, not in your house: garden species pass the cold as eggs in silk sacs, as half-grown young, or as dormant adults tucked into leaf litter, bark and soil, where snow keeps them near freezing rather than far below it. The spiders you see indoors in autumn and winter are mostly house-adapted species that were already living inside. The University of Washington’s Burke Museum estimates that fewer than 5 per cent of the spiders seen indoors have ever been outdoors. Many outdoor adults do die at the first hard frost, but the species survives through its eggs and young.
The idea that spiders flood indoors to escape the cold is one of the most repeated claims in pest advice, and it does not survive contact with the research. What actually happens in winter depends on which spider you are looking at, so the useful answer comes species by species, with the temperatures that matter.
Where each kind of spider spends the winter
| Spider | Winter stage | Where it spends winter | Will you see it indoors in winter? |
|---|---|---|---|
| Yellow garden spider and other big orb weavers | Eggs and spiderlings in a sac; the female dies | Egg sac hung in vegetation outdoors | No |
| Wolf spiders | Fertilised females and half-grown young | Retreats in soil, under boards, stones, firewood and siding | Occasionally, a stray from outdoors |
| Bold jumping spider (north) | Immature spiders | Sheltered sites outdoors | Rarely |
| Sheetweb and dwarf spiders | Juveniles and adults, still active | Leaf litter under the snow | No |
| Common house spider | All stages | Inside buildings, and outdoors on structures | Yes, fewer than in summer |
| Cellar spiders | All stages | Basements, crawlspaces, ceiling corners | Yes, all year |
| False black widow | All stages | Inside houses, garages and carports | Yes, all year |
The pattern is simple once it is laid out: outdoor spiders stay outdoors, and indoor spiders were never outdoors. Penn State Extension says wolf spider females overwinter in protected locations, “including human-made structures”, which is why a wolf spider in a garage in January is not unusual. A single one is not a sign of an infestation, as our wolf spider guide explains.
Do spiders die in winter?
Many adults do, but very few species depend on adults surviving. The Missouri Department of Conservation notes that most spiders in a temperate climate live only about a year and die with the first hard freeze. The University of Georgia’s autumn spider note makes the same point about orb weavers: the first hard frost will kill them, but by then they have mated and made egg sacs that overwinter and re-establish the population next spring.
Kansas State University describes the yellow garden spider’s version. The female produces an egg sac in the fall holding 400 to 1,200 eggs, suspended in the web, then dies. The spiderlings overwinter inside the sac and emerge in spring. The big orb weavers by your porch light in September are the end of a one-season life cycle, which our orb weaver guide and spider lifespan guide cover in more detail.
Other groups carry adults or young through. Penn State says wolf spider males die before winter, while mated females overwinter and produce egg cocoons the following May or June; their spiderlings reach only half their full size by the next winter and overwinter again before finishing growth. In the north, the bold jumping spider overwinters as an immature spider and matures in spring, according to a 2024 study in the Journal of Arachnology. In warmer regions, the same study notes, all ages can be found through the year and the overwintering period is shortened or absent.
Do spiders hibernate?
Not in the way a mammal does. Spiders are cold-blooded, and the Burke Museum puts it this way: they do not shiver or get uncomfortable when it is cold, they just become less active and eventually dormant. That dormancy is the “hibernation” people imagine, and it happens wherever the spider already lives, under bark, in litter, in soil or inside the egg sac.
Some spiders do not go dormant at all. A University of Manitoba study by C. W. Aitchison found at least 54 species winter-active in central southern Canada, mostly tiny sheetweb and dwarf spiders, with wolf spiders, sac spiders, crab spiders and cobweb spiders also represented. In a companion study, winter-active spiders fed at 2°C (about 36°F), less often at minus 2°C (28°F) and rarely at minus 5°C (23°F), eating springtails that are active in the same space under the snow. Studies Aitchison reviews record dwarf spiders active under 60 to 80 cm (two to two and a half feet) of snow at temperatures around 0°C in Finland.
Snow is the key. Those Finnish records come from litter that sat around 0°C under deep snow, whatever the air above was doing, so a leaf-filled border is not a harsh place to spend the winter. It is a refuge, and a tidy garden with every bed raked bare removes some of it.
What temperature do spiders die in the cold?
There is no single number, because spiders harden themselves through autumn. The research gives a usable range.
| Threshold | Temperature | Source |
|---|---|---|
| Most temperate spiders will not freeze above this | 23°F (minus 5°C) | Burke Museum |
| Winter-active spiders still feed | 36°F (2°C) | Aitchison 1984 |
| Winter-active spiders rarely feed | 23°F (minus 5°C) | Aitchison 1984 |
| Bold jumping spider freezing point, September (Michigan) | About 24°F (minus 4.7°C) | Henshaw et al. 2024 |
| Bold jumping spider freezing point, November to January (Michigan) | About 9°F (minus 12.9°C) | Henshaw et al. 2024 |
| Lowest individual freezing points measured | About 5 to 0°F (minus 15 to minus 18°C) | Henshaw et al. 2024 |
The Burke Museum says most temperate spiders carry enough “antifreeze” that they will not freeze at any temperature down to minus 5°C, and some can go colder. The 2024 study of the bold jumping spider shows how that works in practice. Field-collected Michigan spiders lowered their supercooling point, the temperature at which their body fluids freeze, from minus 4.7°C in September to minus 12.9°C in November, then held there through January.
Two details from that study answer the question directly. Freezing is fatal: every spider that froze was dead on warming, while every spider that cooled without freezing was alive and feeding a week later. And origin matters: Michigan spiders survived simulated freezing conditions in December and January at high rates, while nearly all spiders from Texas and Oklahoma died. A southern spider is not built for a northern winter.
Do spiders come inside in winter?
Very few do. The Burke Museum’s arachnologist Rod Crawford explains that house spiders belong to a small number of species specially adapted for indoor conditions: constant climate, poor food supply and very poor water supply. They colonise new houses as egg sacs carried in on furniture and building materials, and they usually spend their whole life cycle in, on or under the same building. Outdoor species, in contrast, are not adapted to indoor life, and the few that end up inside die or at least do not reproduce. As Crawford puts it, any North American spider that needed artificial shelter for the winter would have gone extinct long before Europeans arrived.
Indoor spiders are nearly universal. A 2016 survey of 50 houses in and around Raleigh, North Carolina, published in PeerJ, found spiders in every one. Cobweb spiders, the family that includes the common house spider and the false widows, turned up in all 50 homes, and cellar spiders in 84 per cent.
Many of the less common families on that chart, such as orb weavers, sheetweb spiders and crab spiders, are outdoor animals that wandered or were carried in. The study’s authors note that much of the indoor diversity was filtered in from the surrounding landscape rather than living there. Those strays are the spiders that do not last indoors.
Why you see more spiders indoors in autumn
The autumn rush is about sex, not temperature. The Burke Museum says that when large numbers of house spiders appear at one time of year, it is usually August and September, coinciding with the mating season, and what you are seeing is sexually mature males wandering in search of females. The females and young stay hidden in crawlspaces, wall voids and storage areas. Our guide to getting rid of spiders in the house covers what to do about them; most need nothing more than a vacuum.
Which spiders stay visible through winter: what the records show
We looked at when people in the US record spiders on iNaturalist, adjusting each month for how many observations of anything people logged that month. An index of 100 is a spider’s average share of records; 200 is double its usual share.
Spiders as a whole fall to an index of 46 in January, against a peak of 184 in September. The common house spider follows the outdoor curve, from 174 in September to 49 in January, because many live on the outsides of buildings and mature in summer. Two groups break the pattern. Cellar spiders hold at 100 in January, exactly their yearly average. False black widows, which Penn State describes as common in homes and other structures with all stages found in buildings throughout the year, reach 198 in November and 147 in January.
The January comparison makes the split obvious. Outdoor species collapse: the hobo spider sits at 24, the bold jumping spider at 27 and orb weavers at 34. The indoor specialists stay at or above their usual share. Part of that winter rise is people noticing indoor spiders when little else is about, so treat these as records of sightings, not counts of infestations. These are records of where and when people photographed and identified spiders, mostly outdoors.
Where do spiders go in the summer?
Into the shade, mostly. The Burke Museum points out that low moisture makes summer a worse time for many spiders than autumn (October to December) and spring, and that in mild climates winter can be better than summer. Spiders that seem to vanish in a dry summer are usually sheltering in litter, under bark and in soil, or are present as small immatures that few people notice. The big, conspicuous species that mature in late summer, larger orb weavers and the giant house spiders, give the false impression that spiders are most numerous then.
Should you put a winter spider outside?
Usually not. The Burke Museum’s advice is blunt: you cannot put a spider back outside if it was never outside in the first place, and some house species, native to other climates, perish quickly when removed from indoor shelter. Putting one out on a January night is likely to kill it. If a spider in the house bothers you, moving it to a garage or basement is a gentler option, and leaving it usually does no harm: the common indoor species are harmless and eat other pests.
If you are finding several kinds of insects indoors in winter rather than spiders, that is a different set of animals, the overwintering invaders and the indoor breeders, which our guide to bugs in the house in winter sorts out. A steady supply of spiders indoors usually means a steady supply of their prey, and the place to start is the insects. Large numbers of spiders, or any spider you suspect is a widow or a recluse, are worth identifying with our spider identification guide and, where needed, a licensed professional.
Frequently asked questions
Do spiders die off in the winter?
Many outdoor adults do, but the species survive. Orb weavers die after laying eggs, and the spiderlings overwinter in the sac. Wolf spiders overwinter as mated females and half-grown young, and some tiny sheetweb spiders stay active under the snow. The Burke Museum says most temperate spiders will not freeze above about 23°F (minus 5°C), and hardened jumping spiders in Michigan reached about 9°F before freezing.
What’s the worst month for spiders?
For sightings, September. In our analysis of US iNaturalist records, spiders peak at an index of 184 in September, nearly twice their usual share, and stay high in October at 165. The Burke Museum says house spiders appearing in numbers usually do so in August and September, when mature males wander looking for mates. January is the quietest month, at 46.
What do spiders absolutely hate?
Very little has been proven. A 2018 study in the Journal of Economic Entomology found mint oil and chestnuts repelled two of three spider species tested, while lemon oil had no effect on any of them. The Burke Museum notes that spiders seldom show signs of detecting airborne odours. Fewer insects indoors and sealed gaps do more than any scent.
Why should you never kill a spider in your house?
There is no rule against it, but most house spiders are harmless and eat flies and other pests. Moving them outside in winter is often worse than leaving them: the Burke Museum notes that many house spiders are indoor species that were never outdoors, and some die quickly when put out. Leaving them, or moving them to a garage, is the gentler option.
Do spiders come inside to get warm?
Almost never. Spiders are cold-blooded and not attracted to warmth, according to the Burke Museum, which estimates that fewer than 5 per cent of spiders seen indoors have ever been outdoors. House spiders are a small set of species adapted to indoor life. Outdoor spiders that end up inside usually die or fail to reproduce, so they gain nothing by coming in.
Sources
- Burke Museum, University of Washington, Spider Myths (Rod Crawford): Spiders come into houses in the fall to get out of the cold; Spiders are most numerous in late summer; Putting house spiders back outside; Spider repellents.
- Penn State Extension, Wolf Spiders; False Black Widow Spider.
- Kansas State University, Kansas Bugs: Yellow Garden Spider, 2026.
- University of Georgia CAES Field Report, Autumn spiders.
- Missouri Department of Conservation, Field Guide: Common House Spider.
- Henshaw MT et al. Cold tolerance strategy, supercooling, and cold hardening in three populations of the jumping spider Phidippus audax. Journal of Arachnology 52:143 to 150, 2024.
- Aitchison CW. The phenology of winter-active spiders. Journal of Arachnology 12:249 to 271, 1984.
- Aitchison CW. Low temperature feeding by winter-active spiders. Journal of Arachnology 12:297 to 305, 1984.
- Bertone MA et al. Arthropods of the great indoors: characterizing diversity inside urban and suburban homes. PeerJ 4:e1582, 2016.
- Fischer A, Ayasse M, Andrade MCB. Natural Compounds as Spider Repellents: Fact or Myth? Journal of Economic Entomology 111(1), 2018.
- The Pest Control Brief analysis of iNaturalist research-grade records, pulled October 2026.
