Giant House Spider vs. Hobo Spider: How Can You Tell Them Apart?
You can tell a giant house spider from a hobo spider by comparing overall size and leg length, abdominal markings and coloration, typical web placement and structure, and the behavior of wandering males: giant house spiders are generally larger with very long, spindly legs and a more tapered abdomen, while hobo spiders are somewhat smaller with a stouter body, subtler chevron markings, and a tendency to build low funnel-style webs in ground‑level crevices or basements. Visual clues such as the spider’s posture (giant house spiders often hold their legs in a distinctive angular stance) and where you encounter the web (upper corners, attics or eaves versus low walls and foundation gaps) are among the most practical field signs for distinguishing the two.
This distinction matters to Pacific Northwest homeowners because both species are well established across Washington and Oregon and are commonly encountered in and around houses here: the region’s mild, wet climate and abundant wooded and grassy habitat support year‑round spider activity and create many sheltered entry points into structures. Misidentifying these spiders can lead to unnecessary alarm—hobos were once blamed for serious bites despite limited evidence of medical risk—and can influence where and how homeowners focus exclusion and prevention efforts, since the two species favor different microhabitats within buildings.
How to visually distinguish giant house spiders and hobo spiders in Seattle homes
Giant house spiders (Eratigena atrica species complex) are noticeably larger than hobo spiders (Eratigena agrestis): adult giant house spider bodies typically range from about 7–18 mm in length with legspans commonly 45–75 mm (1.8–3 in), whereas hobo spider bodies are usually 6–9 mm with legspans around 20–35 mm (0.8–1.4 in). That difference is the quickest field cue in a Seattle basement, garage or upper-story corner—if the overall legspan approaches several inches and the legs are long and spindly relative to the abdomen, you are almost certainly looking at a giant house spider rather than a hobo.
Color and pattern differences help at close range: giant house spiders are generally tan to dark brown with a mottled or longitudinally streaked abdomen and relatively distinct banding on the legs (lighter rings separated by darker segments). Hobo spiders tend to be more uniformly brown with a reddish or rusty cast and a series of faint V-shaped or chevron markings down the dorsal abdomen; their legs are usually less distinctly banded and appear thicker relative to the body. Under good light (daylight or a strong flashlight) these contrasts are visible without measuring, especially on specimens 10 mm or larger.
Posture and leg proportions are also diagnostic indoors: giant house spiders have very long first and second legs and a narrow, elongated abdomen, giving a long-legged, “spider-on-a-stick” silhouette when they sit on ceilings or vertical surfaces. Hobo spiders present a stockier profile with proportionally shorter legs and a more compact abdomen. In Seattle homes where ceiling height and corner angles are shallow, the giant house spider’s long legs often extend well beyond the footprint of a hobo spider caught in the same location, making comparison straightforward.
Seasonal timing and microhabitat can confirm visual ID when patterns are ambiguous. Both species become more visible from late summer into autumn (August–October) when males wander to find mates, but in the Pacific Northwest’s mild, humid climate giant house spiders are frequently found on upper-story walls and ceilings year-round in heated houses, while hobo spiders are encountered more often near ground-level entry points, basements, and wood piles where damp conditions favor them. Combining size, leg proportion, abdominal patterning and where in the house the spider is found will let a Seattle homeowner reliably tell the two species apart.
Which species is more common around Seattle and the Pacific Northwest
Across Seattle-area homes the larger “giant house spider” complex (Eratigena spp., formerly Tegenaria) is encountered more often than the hobo spider (Eratigena agrestis). Giant house spiders commonly reach body lengths of 7–18 mm with leg spans frequently 45–75 mm (1.8–3.0 in), so they are the bulk of reports about big, fast house spiders in upper rooms, eaves and attics. Hobo spiders are generally smaller by eye and measurement: adult bodies around 6–9 mm and leg spans more often in the 20–40 mm range, and so they are proportionally less reported as the large, dramatic indoors sightings Seattle homeowners describe.
Seasonal activity also shifts encounter rates: males of both species wander in late summer into autumn, producing spikes in indoor sightings from August through October. In Seattle, where average September highs are roughly 68°F (20°C) and seasonal humidity remains high, those late-summer dispersal movements are prolonged compared with colder regions, so giant house spider males — because they grow larger and live higher in structures — are more likely to be noticed moving across ceilings and window frames during that August–October window. Hobo males also move then but tend to work along ground-level thresholds, so their peak indoor encounter rate is often lower in multi-story dwellings.
Geographically within the Pacific Northwest the two species overlap but show different micro-distributions. Hobo spiders are established across parts of western Washington and Oregon, favoring ground-level, disturbed sites such as foundation walls, rock piles and basement manifolds; their regional distribution is patchy, especially east of the Cascade Range. Giant house spiders thrive in urban and suburban structures throughout Seattle, from low-elevation neighborhoods to higher-elevation houses, because they readily occupy attics, eaves and high interior corners year-round and tolerate the drier microclimates of upper stories.
Because homeowners and pest reports often conflate the two, the relative frequency of sightings in Seattle is influenced by where people live in a house and the time of year. If reports come from upper-story rooms or garages and the spider measures closer to 50–75 mm leg span, it is far more likely to be a giant house spider; if the observation is at foundation level, in basements or among ground vegetation and the specimen measures under ~40 mm leg span, a hobo spider is relatively more probable — but overall giant house spiders are the more commonly encountered large funnel-web spiders inside Seattle homes.
Do hobo spiders pose a medical risk to people in the Pacific Northwest
By current medical and entomological consensus, the hobo spider (Eratigena agrestis) is not considered a reliably medically significant species. Concerns arose in the 1980s–1990s after a cluster of ulcerative skin lesions in the Pacific Northwest were tentatively linked to hobo spiders, but follow‑up laboratory and case‑review work in the late 1990s and 2000s failed to reproduce a consistent necrotic effect from hobo venom. Public health authorities and peer‑reviewed literature now characterize confirmed necrotic bites from hobo spiders as unproven; rigorous case definitions require capture and expert identification of the specimen plus exclusion of other causes, and those criteria have not produced verified necrosis attributable to Eratigena agrestis.
Bites attributed to hobo spiders are rare, and the clinical picture when a bite is witnessed or confidently identified is usually mild. Adult hobo bodies measure roughly 6–14 mm (legspan commonly under 40–50 mm), and their chelicerae are relatively small; documented bites produce brief local pain, transient erythema and minor swelling that typically resolve within 3–10 days. This contrasts with verified necrotic Loxosceles (brown recluse) envenomations, where sphingomyelinase D in the venom causes progressive necrosis over 2–7 days and, in a subset of cases, systemic symptoms. Brown recluses are not established in the Seattle area, and the biochemical components associated with recluse necrosis have not been demonstrated as clinically significant in hobo venom.
Regional ecology affects both encounter rates and the pattern of reported bites. Hobo spiders are an introduced species to the Pacific Northwest and reach adulthood and peak dispersal in late summer through early fall (roughly August–October), which is when most homeowner reports occur. Seattle’s cool, moist climate and houses with basements or ground‑level storage offer suitable refuges, so indoor sightings tend to involve lower stories, crawlspaces and foundation cracks rather than high ceilings. By comparison, giant house spiders (Eratigena/ Tegenaria species), which often have larger adult bodies (commonly 9–18 mm) and legspans exceeding 45 mm, are more frequently seen on upper walls and near windows; complaints about bites sometimes stem from misattributing a transient pain from a giant house spider to a hobo spider sighting.
Clinically and diagnostically, the challenge is misattribution: there is no routine clinical assay to detect “hobo spider venom” in a lesion, and definitive attribution requires capture and taxonomic confirmation within a narrow timeframe. Many wounds labeled as “spider bites” in the PNW are bacterial infections (including MRSA), vascular ulcers or arthropod bites from other insects. In reviews of suspected hobo‑bite cases over the last two decades, hospitals and public health investigators in North America have not produced well‑documented, laboratory‑confirmed cases of hobo‑induced dermonecrosis, so for Seattle clinicians and informed homeowners the working expectation remains that an unobserved skin lesion is far more likely to be non‑arachnid in origin.
What differences in web structure and habitat help tell them apart in PNW homes and yards
Both species are members of the funnel‑web family (Agelenidae) and build a flat, horizontal sheet of silk that leads to a tubular retreat, but scale and placement diverge. Giant house spider (Eratigena atrica complex) webs in occupied rooms frequently span large areas — 0.2–1.0 m² is common indoors — with a noticeable funnel back in a corner or rafter. Those webs regularly include long, radiating “signal” threads that bridge open space (10–40 cm long) so the spider can detect prey at a distance. Hobo spider (Eratigena agrestis) sheets are typically much smaller and denser, often under 0.05–0.3 m², and form a low, ground‑hugging mat that leads into a shallow funnel rooted in soil, debris or foundation crevices.
Vertical placement is a reliable field cue in Seattle houses and yards. Giant house spiders most often position their webs high — on ceilings, in attic rafters, at the tops of doorframes or in the upper corners of garages — commonly 1.5–3 m above the floor. Conversely, hobo spiders build their horizontal sheets within a few centimetres of the ground (0–30 cm), along foundation walls, under rockery, inside stacked wood or beneath patio pavers. Seattle’s mild, damp climate makes basements and crawlspaces suitable for both, but the giant house spider favors elevated, undisturbed indoor corners while the hobo prefers sheltered, ground‑level retreats.
Seasonal patterns tied to web presence also differ in the PNW. Giant house spider males do most of their wandering in late summer through early autumn (August–October), so large ceiling‑spanning webs are often abandoned or missing a resident male by late fall; inhabitants therefore see more loose webs and roaming long‑legged males at that time. Hobo spiders are more sedentary around foundations and maintain and repair their low sheets year‑round, with peak prey‑capture activity and web repair in late spring and summer when insect activity along lawn edges and mulch beds increases in the Puget Sound region.
When combining web structure with spider size and location, practical identification becomes specific: giant house spiders are visibly larger, with legspans commonly in the 45–70 mm range, and their high, messy funnel webs feature long bridging lines and a deeper funnel several centimetres across. Hobo spiders are smaller (legspans typically 20–35 mm), and their sheets are tighter, flatter and directly against the substrate, with the funnel entering a crack or soil pocket rather than a high corner. In short, find a large, elevated sheet with long signal threads and a deep corner funnel and you’re likely looking at a giant house spider; find a compact, ground‑level mat leading into a shallow funnel at the foundation and the hobo spider is the more probable builder.
Practical steps Seattle homeowners can take to identify and control giant house spiders and hobo spiders
For quick field identification, measure body length and legspan with a ruler or by photographing the spider next to a US quarter (≈24 mm) for scale. Adult giant house spiders you’ll see indoors in Seattle typically have elongated bodies roughly 8–18 mm long and legspans commonly in the 40–75 mm range; hobo spiders generally show shorter legs relative to body, with body lengths around 6–14 mm and legspans closer to 20–40 mm. Note posture and movement: giant house spiders run rapidly up walls and across ceilings and will often sit out in web corners, whereas hobo spiders usually stay low near the floor in horizontal funnel webs and retreat into cracks when disturbed. Use those proportional measurements (legspan : body length ≈ 2.5–5× for giant house spiders vs ≈ 1–2.5× for hobo spiders) as a practical rule-of-thumb during inspection.
Web location and structure are diagnostic in Seattle homes and yards. Giant house spiders build sheet-like webs with a funnel retreat that is commonly anchored in ceiling corners, behind crown molding, or under attic insulation; these webs frequently span 30–60 cm across and are suspended several feet off the ground. Hobo spider webs are typically lower, flatter, and more closely attached to the ground or foundation—found in basements, between stacked firewood, under concrete steps, or in rock walls—and the sheet area is usually smaller (10–30 cm) with the funnel opening directly into ground-level crevices. During late summer and early fall (July–October) increased male movement makes both web and wandering-spider sightings more likely; record the web height and horizontal vs. vertical orientation when documenting which species you’re dealing with.
Inside control focuses on exclusion, humidity control, and targeted removal. Seal gaps of 3 mm (1/8 inch) or larger around utility penetrations, windows, and door sweeps—hobos in particular exploit foundation cracks and torn screens. In damp Seattle basements maintain relative humidity below roughly 50% with ventilation or a dehumidifier, since lower humidity reduces the indoor insect prey base and makes crawlspaces less hospitable; clear away cardboard and storage that provides harborage within at least 30–60 cm of foundation walls. Place glue boards or low-profile sticky traps every 0.9–1.8 m (3–6 ft) along baseboards and near basement stairs to monitor activity; check traps weekly for a month to detect seasonal spikes in male dispersal.
Active removal and safe handling reduce indoor populations quickly. Vacuum webs, egg sacs (typically 4–8 mm, silk-enclosed), and unwelcome adults on a weekly or biweekly schedule in problem rooms, then empty the vacuum canister or discard sealed bag within 24 hours. For sample-based identification, confine a spider in a clear jar and photograph dorsal and lateral views with a small coin for scale; document web type and exact location (e.g., “basement, against the west foundation, 10 cm above concrete”) and compare proportions rather than color alone. If chemical control is chosen, apply residual perimeter treatments or crack-and-crevice dusts to foundation gaps and junctions in late summer (July–September) when roaming males are most active; follow label instructions for product rates and indoor use, and consider professional assessment for large or persistent infestations.
How can I tell a giant house spider from a hobo spider?
Compare overall size and leg length, abdominal patterning, posture, and web placement: giant house spiders typically have bodies ~7–18 mm and legspans ~45–75 mm with long, spindly legs and banded legs, while hobo spiders are usually smaller (body ~6–9 mm, legspans ~20–35 mm) with a stouter abdomen and faint chevrons. Giant house spiders favor high corners and ceilings and hold a long‑legged, angular posture; hobos build low, ground‑level funnel webs and appear stockier with proportionally shorter legs. Using a coin or ruler for scale and noting web height often makes identification straightforward.
Are hobo spider bites dangerous in Seattle?
Current medical and entomological consensus is that hobo spiders (Eratigena agrestis) are not reliably medically significant and confirmed necrotic bites have not been demonstrated. Documented or witnessed hobo bites are rare and typically cause only brief local pain, minor redness, and swelling that resolve in days. Brown recluse spiders, which can cause necrosis, are not established in the Seattle area, so most unexplained skin lesions are more likely to be non‑arachnid causes.
Where in my house am I most likely to find a giant house spider versus a hobo spider?
Giant house spiders are most often found high on ceilings, in attics, eaves, upper corners or window frames and build larger, elevated sheet‑and‑funnel webs. Hobo spiders are more common at ground level—basements, foundation walls, under wood piles or between pavers—and construct smaller, low, ground‑hugging sheet webs that lead into cracks or soil pockets.
What should I do to prevent or control giant house spiders and hobo spiders?
Focus on exclusion and habitat modification: seal gaps ≥3 mm (1/8 in) around foundations, windows and utility penetrations, reduce basement/crawlspace humidity to about 50% or lower, and clear storage or vegetation within ~30–60 cm of foundation walls. Use sticky traps along baseboards to monitor activity, vacuum or remove webs and adults regularly, and for identification confine a specimen in a clear jar and photograph with a coin for scale. If chemical control is considered, apply labeled perimeter or crack‑and‑crevice treatments in late summer (when males disperse) or consult a pest professional for persistent problems.