Spiders in Winter: Where They Go and What to Expect

As temperatures drop, spider sightings change. Some species seem to disappear entirely, while others become more visible indoors. Understanding what spiders do in winter helps you manage expectations and plan your spider control strategy.

What Happens to Outdoor Spiders in Winter?

Cold-Hardy Species

Many spiders survive winter through cold-hardening — producing antifreeze-like compounds (glycerol and other cryoprotectants) in their body fluids that prevent ice crystal formation. These spiders overwinter in sheltered spots under bark, in leaf litter, or in other insulated locations, entering a state of reduced metabolic activity.

Seasonal Life Cycles

Some spider species, including many garden spiders and orb weavers, die in late fall after producing egg sacs. Their eggs overwinter in protective silk sacs and hatch in spring, starting the life cycle anew.

Migration Indoors

Some spiders that typically live outdoors move into sheltered structures as temperatures drop. However, this migration is less common than most people think. The majority of spiders you see inside during winter were already living indoors.

Indoor Spiders in Winter

Already Residents

Many indoor spiders — house spiders, cellar spiders, and others — live year-round inside your home. These species are not affected by outdoor temperatures because they live in the climate-controlled indoor environment. You may notice them more in winter because:

• You spend more time indoors.
• The home is sealed tighter, concentrating both spiders and their prey.
• Heating systems create air currents that disturb spiders.

Fall Carryover

Many of the spiders you see inside during winter entered (or became visible) in fall during mating season. Male spiders that wandered inside while searching for mates may still be alive and active during winter months.

Reduced Activity

Even indoor spiders may show reduced activity in winter. Lower temperatures in unheated areas like garages and basements slow spider metabolism, making them less active but not dormant.

Winter Spider Control

Advantages of Winter Treatment

Winter is actually a good time for spider control:

• Spider populations are concentrated in predictable locations.
• Reduced activity makes them easier to catch with sticky traps.
• Egg sacs laid in fall can be found and removed before spring hatching.
• Sealing entry points during winter prevents spring re-entry.

Winter Control Steps

1. Inspect basements, garages, and storage areas for spiders, webs, and egg sacs.
2. Remove all webs and egg sacs you find.
3. Place sticky traps along walls to catch remaining spiders.
4. Seal cracks and gaps now, before spring.
5. Reduce clutter in storage areas during winter cleaning.
6. Apply diatomaceous earth in cracks and along baseboards.

Preparing for Spring

The spiders you see in spring are either overwintered adults or newly hatched spiderlings from fall-laid egg sacs. Removing egg sacs during winter is one of the most impactful things you can do for spring spider control.

Common Winter Spider Species Indoors

House Spiders

House spiders are active year-round indoors. They are buffered from outdoor temperatures and continue building webs, catching prey, and reproducing throughout winter.

Cellar Spiders

Cellar spiders remain active in basements and crawl spaces where temperatures stay relatively stable even in winter.

Brown Recluses

In their range, brown recluses remain active indoors during winter. They may be less visible due to reduced activity levels but are still present in wall voids, closets, and storage areas.

Wolf Spiders

Wolf spiders that entered homes in fall may persist through winter. In unheated spaces, they become sluggish but can survive cold temperatures. In heated living spaces, they may remain active.

The "Release a Spider in Winter" Question

A common dilemma: if you catch a spider inside during winter, should you release it outdoors? For species that are adapted to indoor living (house spiders, cellar spiders), releasing them in freezing temperatures will likely kill them. If the goal is humane removal, relocate indoor-adapted species to a garage or basement rather than putting them outside in winter.

For species that are clearly outdoor wanderers (wolf spiders, jumping spiders), releasing them near your foundation in a sheltered spot gives them the best chance of finding winter shelter.

For year-round spider management, see spider prevention tips and how to get rid of spiders. For comprehensive information, visit our complete guide to spiders.

Expert Insights

Winter spider behavior is a topic I have studied closely throughout my 15-year career. Contrary to what many clients believe, most of the spiders they see indoors during winter did not just come in from the cold. Many indoor spider species, like house spiders and cellar spiders, live their entire lives inside and are active year-round. The seasonal increase in indoor sightings often correlates with male spiders becoming more mobile as they search for mates in the fall and early winter. — Sarah Mitchell, BCE

Sources and References

• University of California Riverside Spider Research
• Burke Museum of Natural History and Culture
• Ohio State University Extension

Main Causes

Indoor spiders activity reflects two drivers — a hospitable indoor environment and a sufficient supply of insect prey. Spiders enter through gaps under doors, around windows, utility penetrations, and any opening leading to attics, basements, garages, or crawl spaces. Once inside they settle wherever undisturbed corners, low light, and easy prey access converge. Cooler weather pushes outdoor species inside in late summer and fall as they seek mating sites or shelter. The most important upstream driver is the indoor insect population — homes with active fly, gnat, moth, or other pest activity sustain larger spider populations than homes without prey. Cluttered storage areas, accumulated webbing, and outdoor lighting that draws nocturnal insects all amplify the indoor pressure.

How to Identify

Identification matters because risk and control differ significantly by species. Most household spiders — cellar spiders, common house spiders, jumping spiders, wolf spiders — are harmless and beneficial. Two species in North America warrant caution: the black widow with its shiny black abdomen and red hourglass marking, and the brown recluse with its violin-shaped marking and uniform tan-brown coloring without leg banding. Check webs for shape and structure: tangled cobwebs in corners indicate cellar or common house spiders; funnel-shaped webs near ground level indicate funnel-web species; sheet webs across grass are usually grass spiders. Single sightings without webs are usually transient outdoor species and do not indicate an infestation.

Risk and Severity

Most spiders found in and around North American homes pose no medical risk to humans and provide net benefit by reducing other pest populations. Two species warrant medical caution: the black widow, whose venom can produce systemic symptoms including muscle cramping, abdominal pain, and elevated blood pressure; and the brown recluse, whose bite can produce a slowly developing necrotic lesion in a minority of cases. Bites from either species generally respond well to medical care, and fatalities are extremely rare. The far more common spider-related problem is aesthetic — webs, egg sacs, and visible spiders cause distress without medical significance. Risk concentrates in undisturbed storage areas, garages, basements, and outbuildings.

Solutions and Actions

For most spider species the goal is removing webs and reducing prey rather than chemical treatment. Vacuum or sweep down all visible webs weekly, including egg sacs, in garages, basements, attics, eaves, and exterior corners. Reduce indoor insect populations by maintaining screens, sealing entry points, and addressing any active pest issue — fewer insects means fewer spiders. Apply a residual insecticide barrier to the foundation perimeter, around windows and doors, and in eaves to deter newly arriving spiders. For confirmed black widow or brown recluse populations in storage areas, use professional pest control, wear long sleeves and gloves when handling stored items, and shake out shoes and clothing left in garages or basements. Single sightings indoors without webs are usually transient and need no chemical response.

Prevention

Prevention works by reducing indoor prey and limiting entry. Vacuum corners, ceiling angles, undisturbed storage, and basement and garage areas weekly to remove webs, egg sacs, and the dust that supports prey populations. Seal gaps around doors, windows, utility penetrations, and foundation cracks. Address active insect pests promptly because indoor spider populations track prey availability. Switch exterior lights to yellow or warm LED bulbs that attract fewer flying insects, and position outdoor lighting away from doors and windows. Inspect and shake out shoes, gloves, and clothing left in garages, basements, sheds, and storage areas. Trim shrubs and ground cover away from the foundation, and keep firewood and debris stacks at least twenty feet from the structure.

Frequently Asked Questions

Do spiders come inside in the winter?

Some outdoor spiders do seek shelter indoors when temperatures drop, but many of the spiders you see inside during winter have actually been living indoors all along. Indoor spider species like house spiders and cellar spiders are active year-round and do not migrate from outdoors. Ground-dwelling spiders like wolf spiders are more likely to enter in late fall.

Do spiders die in the cold?

Many outdoor spider species die in winter, leaving behind eggs in protected egg sacs that hatch in spring. However, some species are cold-adapted and can survive freezing temperatures by producing antifreeze-like compounds. Indoor spiders are protected from cold weather and remain active throughout winter.

Why am I seeing more spiders in the fall?

The increase in spider sightings during fall is largely due to male spiders becoming more active and mobile as they search for mates. This wandering behavior makes them more visible. Additionally, some outdoor species enter homes seeking warmth. Sealing entry points before fall can reduce the number of new spiders entering your home.

What should I recheck first for spiders in winter?

Recheck the exact place, timing, and repeated signs connected with spiders in winter before changing your plan. A single sighting or old web can mean something very different from fresh activity in several rooms. Confirm whether insects, clutter, moisture, gaps, or stored items are supporting the issue, then match the response to what you actually found.