The short version
Before a pro visits, gather clear photos with a size reference, a captured specimen if you can, and notes on where each spider was found and what web was nearby. Then ask four things: what species or group is this, how confident are you, what features did you use, and does it change the treatment. A pro who names the features and explains how the plan differs for widows or recluses is worth listening to.
- Photos from above and below with a coin for scale make identification possible.
- Web shape and location identify groups more reliably than color.
- Widows and recluses are the two groups that change a treatment plan.
- Ask what features the pro used, not just what the answer is.
- County extension offices and university labs offer a second opinion, often free.
- Research: The bathroom is the room least likely to have spiders, but that still means most do: Bertone and colleagues found them in 68.5% of 146 North Carolina bathrooms in 2012.
For homeowners and renters who have found a spider they cannot place, for parents worried about a spider near a child's bed, and for property managers fielding a tenant claim that a unit has widows or recluses. It is also useful before any spider treatment, since a plan built on the wrong species is aimed at the wrong places.
What to look for
Most misidentifications share a cause: the decision was made from a description or a quick glance, using color and size. Reliable identification uses eye arrangement, markings, web type and location. A pro who visits without a specimen or a clear photo is guessing, however confidently. Spider identification errors run in both directions and both are costly. A harmless brown spider labeled a recluse leads to an expensive, anxious, whole-home program and sometimes to unnecessary medical visits for ordinary skin lesions. A widow in a garage labeled a house spider leads to a perimeter spray that never reaches the low, dark corners where widows live.
- 1Glossy black spider with red hourglass, hanging inverted in a low web.
- 2Uniform tan spider with a dark violin mark behind the head.
- 3Strong, irregular, sticky webs in meter boxes and under decks.
- 4Fast brown spiders in stored boxes and closets.
- 5Flat circular webs with spokes at eaves and fixtures.
- 6Messy tangles in ceiling corners.
Why it’s worth acting soon
- A misidentified widow population stays in a garage children use.
- A harmless spider labeled a recluse triggers unnecessary treatment.
- The specimen gets thrown away before anyone can confirm it.
- Treatment targets eaves when the real species lives in low storage.
- Tenant claims go unresolved for lack of a clear identification.
in the U.S. are the black widow and brown recluseMedically significant spidersUS CDC Treatment options and typical costs
Specimen capture and photo set
No cost: DIY step
Trap the spider under a clear cup, slide card stock beneath, and transfer to a sealed jar; freeze if it must be killed. Photograph top and underside with a coin for scale, plus the web and location.
- Time
- Five minutes
- Best for
- Giving the pro something real to identify
Pro inspection with identification
$75–$200, often credited toward treatment
The technician examines your specimen and photos, then inspects the locations you noted for more of the same species, egg sacs and hiding spots. Ask for the identification on the report.
- Time
- 45 to 90 minutes
- Best for
- On-site identification plus a search for others
Extension office or university identification
$0–$50
Most county extension offices and university entomology labs identify spiders from photos or mailed specimens, often at no charge. Use them when the pro is uncertain or the answer changes the plan.
- Time
- A few days to two weeks
- Best for
- A second opinion on a suspected widow or recluse
Species-specific treatment
$150–$400 initial, more for confirmed recluse programs
Widows: dewebbing and sac removal in low, dark exterior and garage spots, with application there. Recluses: interior crack-and-crevice, glue board monitoring, and storage decluttering across the home.
- Time
- One to three hours initial
- Best for
- Confirmed widow or recluse populations
Prices are typical published ranges. Ask what’s included before you compare quotes.
Mesh and sealant around a pipe entry close off a gap spiders would otherwise use.Collecting the evidence before the visit.
Do not crush it or use spray, which distorts the body. If it needs to be killed, put the sealed container in the freezer overnight; the specimen stays intact. Place a clear cup over the spider, slide a stiff card underneath, and tip it into a jar with a lid or a zip bag. A live capture is best. Egg sacs are worth collecting too, in a sealed bag; widow sacs are tan and papery or spiky, and confirm a breeding population. If you have found more than one, number them and keep them separate. Write all of this on one card with the date. Note whether the spider was in the web or wandering, and the exact place. Note the shape: a flat circle with spokes, a messy tangle, a sheet with a funnel, or a strong irregular web low in a dark corner. Photograph the web and the location. Use good light and get as close as the camera will focus. Put a coin next to it for scale. Photograph before capture if you can: one shot from directly above, one from the side, and, once it is in a clear container, one from below.
The questions and what good answers sound like.
A good answer lists them: the inverted posture and hourglass; the eye arrangement; the violin mark; the web shape. Which features did you use? Confidence without features is a warning sign. A good answer is honest: certain for a widow with the hourglass visible; fairly sure for a wolf spider; not certain for a possible recluse without magnification. How confident are you? A weak answer is a bad one or a harmless one with no name. A good answer names a group at least: house spider, cellar spider, wolf spider, orb weaver, funnel weaver, widow, recluse, jumping spider. What is this? Ask each question and write the answer down. That is what a careful technician does. A good answer is a lab or the extension office. If unsure, what then? The answer should be yes. Will you write it on the report? A weak answer is that the same treatment covers everything. A good answer explains the difference: widows mean low exterior and garage work; recluses mean interior crack-and-crevice work, glue boards and a look through stored items; house spiders mean eaves, fixtures and lighting. Does this change the plan? A weak answer is that it is brown.
Spiders slip into attics through soffit and gable vents, then settle where nobody disturbs them.Second opinions, records and what to do with the answer.
For a widow, focus on low, dark exterior and garage areas: meter boxes, under deck rails, behind stored items, block wall voids, the garage door corners. If the two agree, act on it. Record their answer next to the company's. They see hundreds of samples a year and have no stake in the treatment. Send the same photos and, if possible, the specimen to your county extension office or a university entomology lab. For any identification that changes the plan, get a second opinion. Property managers should attach the identification to the unit file; a written identification from a lab settles a tenant claim faster than any reassurance. Keep the photos, the identification and the features used in your service folder. If the two disagree, the extension office's answer generally carries more weight on the species question; ask the pro to revise the plan. For everything else, the plan is web removal, lighting changes and sealing. For a recluse, expect a longer program: glue boards throughout, decluttering and lidded storage, sealing cracks, interior crack-and-crevice application, and careful habits with stored clothing and bedding. Deweb, remove sacs, and have the pro treat those spots.
What affects the price
- Whether identification is bundled with an inspection fee.
- Confirmed widow or recluse versus nuisance species.
- Number of locations where the species was found.
- Storage and clutter volume that must be searched.
- Garage, shed and crawl space access.
- Glue board monitoring program length.
When to call for help
A good answer is that they will examine the specimen under magnification, tell you what features they see, and send it to a lab if unsure. A pro who says all brown spiders in your area are recluses, or that they do not need to see it, is not the right person. Call a pro when you have a spider you cannot place and it was found where people spend time, when you find several of the same unusual spider or distinctive egg sacs, or when someone in the household has an unexplained bite reaction and a spider was seen nearby. Have the specimen and photos ready. Ask whether the technician is comfortable identifying spiders to group and how they handle uncertain cases.
What you can do yourself
Web type and location alone place most spiders into a harmless group: a flat orb web outdoors, a messy tangle in a ceiling corner, a funnel in the grass, or a long-legged spider that vibrates its web when touched. You can do much of the identification yourself. Insist that the answer be written on the report with the features used. Recluses are difficult even for experienced technicians because several harmless brown spiders resemble them. Widows are distinctive once you see the underside. The cases that need a professional are the two medically significant groups and anything you are unsure about. A photo compared against your state extension office's spider page will confirm it.
Simple ways to keep spiders away
- Keep a clear jar and a card in the garage for quick captures.
- Photograph any unusual spider before disposing of it.
- Shake out shoes, gloves and stored clothing in garages and sheds.
- Store items in lidded bins so recluses and widows have fewer hiding places.
- Wear gloves when moving firewood, stored boxes or meter box covers.
- Deweb low exterior corners, deck undersides and meter boxes monthly.
Monitors along baseboards show whether spider numbers are actually falling after treatment.Did you know?
Brown recluse spiders have six eyes arranged in three pairs.
Only adult female widows have the full red hourglass marking.
Jumping spiders have two very large forward-facing eyes.
Questions people ask
What questions should I ask a pest control technician about a spider?
Does this change the treatment plan, and how? Would you send it to a lab if unsure? Answers that name features and explain plan changes are the ones you want. What species or group is this? How confident are you?
How can I tell a black widow from a common black spider?
Many black spiders are dull or hairy and sit upright. Photograph the hourglass and the inverted posture. Adult female widows are glossy black with a round abdomen and a red or orange hourglass on the underside, and they hang upside down in a strong, irregular web low in dark places.
How do I know if a spider is a brown recluse?
The eye arrangement is the reliable feature and needs magnification. They are established mainly in the south-central United States. Recluses are uniformly tan to brown with no banding on the legs, a dark violin mark on the front body segment with the neck pointing backward, and six eyes in three pairs.
Can a pro identify a spider from a photo?
Recluse identification from photos is unreliable because look-alikes are common, so keep the specimen. A photo with a coin for scale, taken from above and below in good light, gets the best result. Often to group, and usually for widows if the underside is visible.
Does the spider species change how it is treated?
Widows need low, dark exterior and garage spots searched and treated. Recluses need interior crack-and-crevice work, glue boards and storage decluttering throughout. A plan that is the same regardless of species has not used the identification. Yes. Web builders at eaves need dewebbing and exterior work.
Where can I get a spider identified for free?
Search your state's extension service plus spider identification. Include the photos, the location found and the web type. County cooperative extension offices and university entomology departments in most states identify spiders from photos or mailed specimens, often at no charge or for a small fee.
What does a severe spider infestation cost to treat?
Ask whether follow-up visits and a sealing step are part of the price. It's a published estimate, not a local quote. Local quotes vary; ask for a written estimate. Severe cases usually involve more than one visit and exterior work.
How much does it cost to have a house sprayed for spiders?
Many pros combine methods after an inspection. Ask what the price includes and whether interior, exterior or both will be treated. Local quotes vary; ask for a written estimate.
Sources (6)
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