The short version
Most spiders are harmless, but infestations of black widows or brown recluses require professional treatment. Sealing entry points, reducing clutter, and regular spraying can prevent problems.
- Only black widow and brown recluse spiders are medically significant in the US.
- Spiders are most visible in late summer and fall when males roam for mates.
- Professional treatment typically costs $150–$400 per visit.
- Prevention includes sealing cracks, reducing lighting, and removing webs.
- In rentals, regular treatments keep tenant complaints and bite worries down.
- Research: In its January 2025 U.S. cost guide, Local quotes vary; ask for a written estimate.
For homeowners, families with children and pets, and landlords who want to manage spider problems effectively. Landlords will find what to do when a tenant reports spiders, how often to treat, and how to keep a rental comfortable and in good shape; homeowners get the same practical steps for their own place. If you manage multiple units or a single-family rental, the strategies here apply to any property in the US.
What to look for
In severe cases, black widow or brown recluse bites can cause serious health issues, that need medical attention. For landlords, spider complaints are common, especially in late summer when spiders invade homes seeking warmth. A single spider web in a doorway or a spider scurrying across a floor can make a space feel unclean. The real problem with spiders is their visibility and the fear they provoke. Most household spiders, like cellar spiders, jumping spiders, and wolf spiders, are harmless and help control pest insects. On the coasts, brown recluse sightings are rare and often misidentified. Black widows are found throughout the US, while brown recluses are concentrated in the central and southern states—from Nebraska to Texas and east to Georgia. Of the roughly 3,000 spider species in North America, only two groups are considered medically significant: the black widow (Latrodectus) and the brown recluse (Loxosceles reclusa). Spiders are often misunderstood.
- 1Visible webs in corners, window frames, eaves, or basements.
- 2Spiders themselves—especially if you see multiple of the same species.
- 3Egg sacs (small, round, silk-covered bundles) attached to webs or surfaces.
- 4Shed exoskeletons (molted skins) near hiding spots.
- 5Small insects (prey) caught in webs, indicating a food source.
- 6Scatterings of dead insects under webs or in corners.
- 7For black widows: irregular, tangled webs in dark, undisturbed areas like woodpiles or crawl spaces.
Why it’s worth acting soon
- Spider populations can grow rapidly if food sources (other insects) are abundant.
- Dangerous species may establish nests in inaccessible areas, increasing bite risk.
- Webs accumulate dust and debris, reducing property appeal and cleanliness.
- Tenants may break leases or file complaints if infestations are not addressed.
- A tenant bitten by a widow or recluse is a health problem and a landlord problem.
in the U.S. are the black widow and brown recluseMedically significant spidersUS CDC Treatment options and typical costs
Interior & Exterior Chemical Spray
$150–$400
A professional-grade liquid insecticide applied to baseboards, cracks, window frames, and exterior perimeter. Kills spiders on contact and leaves a residual barrier that lasts 30–90 days.
- Time
- 30–90 days
- Best for
- Moderate to heavy infestations; all properties.
Dust Treatment (Crawl Spaces, Attics)
$100–$250
Insecticidal dust (e.g., boric acid or silica gel) applied into wall voids, attics, and crawl spaces where spiders hide. Effective for long-term control in hard-to-reach areas.
- Time
- 6–12 months
- Best for
- Homes with accessible crawl spaces or attics; ongoing prevention.
Web Removal & Vacuuming
$75–$150
Physical removal of webs, egg sacs, and live spiders using a shop vacuum or brush. Often combined with chemical treatment for immediate relief.
- Time
- Immediate, but needs repetition
- Best for
- Light infestations; quick cleanup before chemical treatment.
Prices are typical published ranges. Ask what’s included before you compare quotes.
Crawl spaces and their vents are worth a look with a flashlight, especially if a widow has turned up outside.Understanding Spider Behavior for Better Control.
Knowing where these spiders hide allows for focused inspections and treatments, reducing the risk of bites. Brown recluses are reclusive by nature, hiding in cardboard boxes, clothing piles, and seldom-used corners. For dangerous species like black widows, they favor dark, secluded areas such as woodpiles, sheds, meter boxes, and crawl spaces. Regular cleaning and decluttering remove hiding spots and webs, making the environment less hospitable. For example, reducing indoor lighting and eliminating other insects (flies, ants) can starve spiders out. Understanding these habits helps in targeting treatment and prevention. They may also live in wall voids and emerge at night to hunt. Once inside, they prefer quiet, undisturbed areas like basements, attics, closets, and behind furniture. Spiders can enter homes through tiny cracks, open doors, or on items brought inside. As temperatures drop, spiders seek warm, sheltered spaces indoors—this is when homeowners notice them most. The peak season from August to October corresponds to when many insects are active and male spiders roam to mate. Most spiders are solitary and territorial, but they can build large populations if food is abundant. Their activity is driven by the availability of prey, moisture, and shelter. Spiders are predators that feed primarily on insects.
Health Risks and Medical Significance of Spider Bites.
In areas with known black widow or brown recluse populations, professional pest control is strongly recommended. Preventive measures include wearing gloves when handling firewood or boxes, shaking out clothing and shoes before wearing, and keeping beds away from walls. Medical attention should be sought for any suspected venomous bite, and the spider should be captured if possible for identification. It helps to ask tenants to leave spiders alone and report sightings early. For landlords, the worry is a tenant getting bitten by a widow or recluse on the property, and regular inspections and treatment make that less likely. Most bites occur accidentally. It is important to note that spiders typically bite only when threatened or trapped, such as when rolled onto in bed or when wearing clothing they have entered. However, many suspected brown recluse bites are misdiagnosed; actual bites are uncommon even within their range. Brown recluse venom is cytotoxic, causing tissue damage (necrosis) that can lead to slow-healing ulcers. Bites are rarely fatal to healthy adults but can be dangerous for children, the elderly, or those with compromised health. Black widow venom contains neurotoxins that can cause severe muscle pain, cramps, nausea, and in rare cases, breathing difficulties. The two groups of concern are black widows and brown recluses. Despite common fears, most spider bites are harmless and cause only minor redness or swelling.
The gap under a door is one of the easiest ways in, for spiders and for the insects they follow.Integrated Pest Management (IPM) for Spiders.
IPM keeps product use low while still keeping spiders in check. If treatment is still needed, a pro can put a light dust into voids and treat the exterior perimeter rather than spraying rooms. Use yellow or warm-toned bulbs to draw fewer insects. Outdoors, keep the yard tidy and move woodpiles away from the house. Reduce hiding spots by clearing clutter in basements, garages and attics. Start by removing webs and egg sacs with a vacuum or broom, then find the entry points and seal them. Integrated pest management for spiders combines cleanup, sealing gaps and targeted treatment.
Seasonal Spider Activity and Treatment Timing.
Many companies will come back and re-treat if spiders return within a set period; ask about the terms. New spiders may also wander in from untreated areas, so follow-up inspections are recommended. After treatment, it can take a week or two to see full results as spiders die off. Many pest control companies offer seasonal plans that adjust treatment frequency based on local climate and pest pressure. For landlords, scheduling treatments in early fall (September) can address the seasonal surge and reduce tenant complaints. In southern states like Florida or Texas, spiders remain active year-round, so quarterly treatments are common. In colder northern climates, spider activity drops in winter, but indoor populations may persist in heated spaces. They are more likely to enter homes during this time, and indoor treatments can catch them before they establish. The most critical period is late summer through fall (August–October), when male spiders are actively roaming to find mates. Regular web removal and monitoring are important. Summer sees peak insect activity, which draws spiders. This is a good time for prevention—sealing entry points and applying a perimeter treatment to intercept wandering juveniles. In spring, spider eggs hatch, and spiderlings disperse. Spider activity varies by season, and timing your treatments can improve effectiveness.
What Landlords Are Responsible For.
Your liability insurance may cover a bite claim, but steady pest control makes one much less likely. A short lease clause asking tenants to keep units tidy and report pests early also helps. Your pest control company's service reports show what was done and when. If a tenant reports a bite, respond quickly and write down what you did. Keep the service reports from each inspection and treatment, and a note of every tenant complaint and how you handled it. Good records help everyone. In some states, tenants may withhold rent or break a lease if pest problems are not addressed. While a few harmless spiders do not typically constitute a breach, infestations of venomous species or large numbers of spiders that affect tenants' enjoyment of the property can lead to legal issues. Landlords have a legal responsibility to provide habitable premises, which includes keeping the property free from pests that pose health risks.
What affects the price
- Size of the property (square footage; number of units for landlords).
- Severity of infestation (light, moderate, severe).
- Type of spider (black widow/recluse requires specialized treatment).
- Accessibility of hiding spots (crawl spaces, attics, tall ceilings).
- Number of treatments needed (single vs. quarterly program).
- Geographic region (prices may be higher in urban areas or regions with high pest pressure).
- Additional services like sealing gaps (sealing cracks) or web removal.
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What is your biggest concern about spiders in your home?
When to call for help
You should call a professional pest control company immediately if you suspect black widow or brown recluse spiders in your home or rental property. Also seek professional help if you see multiple spiders daily, find egg sacs, or have children or pets who could be at risk. For landlords, a tenant complaint about spiders is a good reason to book an inspection and keep a note of what was found. Even for harmless species, a pro can identify the source and provide long-term prevention.
What you can do yourself
DIY spider control can work for minor problems: vacuuming webs, sealing cracks, and using over-the-counter sprays like those containing cypermethrin or deltamethrin. However, these products often have short residual effects and may not reach hidden spiders. Professional treatments use stronger, longer-lasting insecticides and application techniques that target hiding spots. For landlords, DIY often falls short, because tenants expect a quick, thorough fix. Many pros will also re-treat if spiders return, which is handy for rentals. The cost of a single professional treatment ($150–$400) is comparable to multiple DIY purchases and offers better results.
Where you live matters
Ask for an inspection before committing to a program. A local pest control company will know the specific species and effective methods for your area. For landlords, understanding regional patterns helps in choosing the right treatment frequency and educating tenants. Dry conditions push spiders indoors seeking water, so fixing leaks is crucial. In the Southwest, desert species like the Arizona brown spider (a relative of the brown recluse) can be found, along with black widows. Treatments should emphasize sealing gaps and moisture control. In the Pacific Northwest, spiders like the giant house spider are prevalent, but venomous species are rare. The mild climate allows for year-round activity, though peaks are still in fall. On the West Coast, especially California, black widows are common in garages, sheds, and landscaping. In Florida, wolf spiders and huntsman spiders are common, and the moist climate means spiders can breed indoors in bathrooms and kitchens. Quarterly treatments are recommended, especially for landlords. Humidity supports larger insect populations, so spiders thrive year-round. Black widows are widespread. In the South and Southeast, the brown recluse is a concern primarily in the central part of the region (e.g., Georgia, Alabama, Mississippi). Treatments should focus on sealing foundations and reducing outdoor lighting. The peak season is pronounced, with spiders entering homes in September and October as temperatures drop. In the Northeast and Midwest, common house spiders and cellar spiders are the main nuisances, with occasional black widows in basements and woodpiles. Spider control needs vary across the US due to climate and species distribution.
Simple ways to keep spiders away
- Seal cracks and gaps around windows, doors, and foundations with caulk or weatherstripping.
- Reduce outdoor lighting near entrances; use yellow or LED bulbs that attract fewer insects.
- Remove clutter in basements, garages, and storage areas where spiders hide.
- Trim vegetation away from the house; keep firewood stored at least 20 feet from the foundation.
- Vacuum regularly, especially in corners and under furniture, to remove webs and egg sacs.
- Install door sweeps and repair torn screens to prevent spider entry.
- Use sticky traps in corners and along baseboards to monitor spider activity.
In apartments, spiders move between units through shared walls and utility gaps, so one unit rarely tells the whole story.Did you know?
Weight for weight, spider silk is stronger than steel.
Spiders can't chew. They liquefy a meal first and drink it.
Some spiders, like the diving bell spider, live entirely underwater by trapping air in a silk bubble.
Questions people ask
What is the best way to get rid of spiders?
The best approach combines prevention (sealing cracks, reducing clutter) with treatment. For light infestations, vacuuming webs and using sticky traps can help. For moderate to heavy infestations, or if venomous spiders are present, professional treatment is recommended. A pest control expert can apply long-lasting insecticides and identify entry points.
Are spiders dangerous to children and pets?
Most spiders are harmless. The black widow and brown recluse are the only US spiders whose bites can cause serious health issues. Children and pets are at higher risk because of their size. If you suspect these spiders, keep kids and pets away and call a professional. Symptoms of a bite include pain, swelling, nausea, and in severe cases, muscle cramps or tissue damage.
How often should I treat my home for spiders?
For most homes, a quarterly treatment schedule is effective. In regions with high pest pressure or venomous spiders, monthly treatments may be needed during peak season (August–October). Many landlords choose quarterly service to keep tenant complaints down.
Can spiders come back after treatment?
Yes, new spiders can enter from outside or from untreated areas. Professional treatments create a barrier that kills spiders on contact and deters new ones, but the barrier degrades over time. Regular follow-up treatments and prevention measures are necessary for long-term control. Many companies will re-treat for free if spiders return within a set period; ask what it is.
What attracts spiders to my home?
Spiders are attracted to homes that offer food (insects), shelter, and moisture. Outdoor lighting that attracts insects, clutter in basements or garages, and gaps around doors and windows all invite spiders. Reducing these attractants can help prevent infestations.
How do I know if I have black widow or brown recluse spiders?
Black widows are shiny black with a red hourglass marking on the underside of the abdomen. They build irregular, tangled webs in dark corners. Brown recluses are light to dark brown with a violin-shaped marking on the back (behind the head). They have six eyes arranged in pairs, while most spiders have eight. If you suspect either, do not attempt to handle them; call a professional for identification and treatment.
Do ultrasonic pest repellers work for spiders?
There is no scientific evidence that ultrasonic devices effectively repel spiders. extension research indicates they have little to no effect. Sticky traps, good sanitation, and professional treatments are proven methods.
What should landlords do if a tenant reports spiders?
Take the report seriously. Keep a note of what was found and done. If venomous spiders are found, treat immediately. Provide tenants with prevention tips (e.g., keep clutter down, seal cracks). Regular inspections and treatments can prevent future complaints.
Is monthly spider control worth it?
In Landlords, most spiders are harmless and beneficial, so the goal is usually to remove the webs and egg sacs and reduce the insects they feed on. In Landlords, only the black widow and brown recluse are medically significant in the U.S., and they are identified by their markings.
Sources (11)
The facts in this article come from the public sources listed above. Every home is different, so ask the company you talk to about pricing and what’s included. Published by Spider Exterminator · Updated September 11, 2026 · How we write these guides