The essentials in 30 seconds
"False widow" is a name for several spiders in the genus Steatoda. The one in the news is the noble false widow (Steatoda nobilis): a body of 7 to 14 mm, a glossy, bulbous, brown abdomen with cream mottling, a pale crescent at the front and a very dark front body. It came from the Canary Islands and Madeira, was first recorded near Torquay in 1879 and is now common across much of southern Britain and spreading north. It lives in window frames, the top corners of rooms, conservatories, sheds and garden walls, in a messy tangle of strong silk. It never attacks unprovoked: bites happen when it is pressed against skin or handled. Most bites cause pain like a wasp sting for a few hours; a minority cause stronger symptoms or an infected wound.
- Wash a bite with soap and water and use a cold compress; see a pharmacist if it looks infected.
- Get urgent help for swelling of the face or throat, difficulty breathing, or a wound that ulcerates or spreads.
- To remove one, place a glass over it, slide a card underneath and release it outside.
How to identify a false widow spider
All false widows share a shiny, rounded abdomen with a narrow pale crescent at the front edge. Markings vary and fade with age, especially in adult females, so check size, legs and where you found it as well.
| Species | Body length | What it looks like | Where it lives |
|---|---|---|---|
| Noble false widow (Steatoda nobilis) | Females 8.5–14 mm, males 7–10 mm | Brown and cream mottling, often described as a skull-shaped pattern; very dark front body; legs reddish to brown, usually without clear bands | Window frames, top corners of rooms, conservatories, kitchens, sheds, walls and fences |
| Cupboard spider (Steatoda grossa) | Females 6.5–10 mm, males 4–6 mm | Darker, with purplish-brown legs; young and males have white spots, adult females are often plain brown | Houses, under furniture and in dark, low corners |
| Rabbit hutch spider (Steatoda bipunctata) | Females 4.5–7 mm, males 4–5 mm | Brown without pale mottling; males often show a light line down the abdomen | Sheds, pet hutches, garden clutter; the most common and widespread |
The Natural History Museum lists six species that are commonly called false widows in the UK, and a seventh, the Mediterranean false widow, which arrives occasionally with imported grapes and other produce but is not established. The tiny rabbit hutch spider is, in the British Arachnological Society's words, extremely unlikely to be able to bite through human skin.
Look-alikes
| Spider | How to tell it apart |
|---|---|
| Missing sector orb weaver | Silvery markings and paler legs; builds a round orb web with one wedge left empty, unlike the false widow's tangle |
| Lace web spider | Matt, hairy abdomen rather than a glossy one; more oval |
| Large house spider | Builds a similar messy web in corners, so check the spider itself for the glossy abdomen and pale crescent |
| Black widow (Latrodectus) | Not established in Britain; the Natural History Museum sees about six a year, usually dead on arrival with imported grapes |
If you still cannot tell, photograph the spider from above next to a coin and use the Natural History Museum's identification service or the British Arachnological Society's Spider Recording Scheme.
Where false widows live in UK homes
The noble false widow likes warm, sheltered, slightly raised spots. The Natural History Museum notes that its webs are usually at least 1.5 m off the ground, and that indoors it favours kitchens and conservatories. Typical places to look:
- Window frames and reveals, where cracks give the web a sheltered retreat.
- Top corners of rooms, porches and conservatories.
- Sheds, garages, garden walls, fences and railings outside.
The web is an untidy, criss-cross tangle of very strong silk with a tube-shaped retreat tucked into a crack or hole. The spider spends most of its life in or near it. Adult males, which are mostly seen between July and November, wander in search of females, which is why sightings indoors rise every autumn. Females can be found all year; they take two years to mature and may live a third.
Is it spreading?
The British Arachnological Society describes the noble false widow as a native of the Canary Islands and Madeira, probably imported repeatedly with bananas. After its first British record near Torquay in 1879, it stayed on the south coast for around a hundred years. The Natural History Museum dates its spread in southern counties from the 1980s; by 2020 it was commonly recorded across much of southern Britain and it continues to move north, which the Society links to a warming climate.
Are false widows dangerous?
False widows are not aggressive. The British Arachnological Society says none of the British species ever attack people unprovoked: the risk comes from putting a hand into a web, handling one roughly, or sitting or lying on one by accident. Of more than 650 British spider species, the Natural History Museum says only around 12 have been recorded biting people, and the Society notes that the noble false widow has a more venomous bite than any native British spider.
| Aspect | What reliable sources report |
|---|---|
| Typical feeling | Pain at the bite, often no worse than a wasp sting, sometimes spreading outward (Natural History Museum) |
| How long | Usually 1 to 12 hours, rarely more than 24 (Natural History Museum) |
| Common signs | Local pain, swelling and sometimes blistering (British Arachnological Society) |
| Less common | A peer-reviewed series of confirmed bites in Ireland and Britain described tremors, fatigue, nausea and low blood pressure in some cases, and some patients needed hospital treatment |
| Infection | Bites can let bacteria into the skin; the Natural History Museum attributes many of the worst wounds reported in the press to infection rather than venom |
What the research says
The best clinical evidence comes from a case series by researchers at the University of Galway, published in the journal Clinical Toxicology in 2021 (print 2022). It reported 16 new confirmed bites, bringing the total of confirmed cases in the medical literature to 24, with symptoms ranging from mild to severe. A separate study by the same group found bacteria, some of them resistant to antibiotics, on the bodies and fangs of noble false widows, which may explain some infected bites. The numbers are small: these papers show that serious reactions are possible, while museum and society experts stress that they are uncommon.
First aid
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01
Move away from the spider
If you can do it safely, trap it in a jar for identification.
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02
Wash the bite
Use soap and water to lower the chance of infection.
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03
Cool it
Hold an ice pack wrapped in a cloth, or a cloth soaked in cold water, on the bite for at least 20 minutes, and raise the area if you can.
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04
Ease the pain
Paracetamol or ibuprofen can help. A pharmacist can advise on antihistamines or creams for itching and swelling.
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05
Leave it alone
Avoid scratching and home remedies; keep the wound clean while it heals.
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06
Watch it for a few days
Photograph it daily. Seek help, as in the box above, if pain grows, the redness spreads, pus appears or you feel unwell.
Myths in the press
| Claim | What the experts say |
|---|---|
| "Killer spiders are invading Britain" | The species has lived on the south coast since the 19th century; the British Arachnological Society traces the scare to wildly inaccurate media claims in 2013 |
| "They are as dangerous as black widows" | They are distant cousins with much less potent venom, and the Natural History Museum says they are not the deadly spiders they are sometimes thought to be |
| "They chase or attack people" | They are shy and sluggish and bite only when trapped or handled |
| "Every spider bite in autumn is a false widow" | Spiders are blamed for many wounds that are actually insect bites or infections; the spider is rarely caught for identification |
| "You need to fumigate the house" | A few spiders in window frames call for a glass and a card, not chemicals |
To keep it in proportion, the British Arachnological Society notes that the chance of a spider bite in Britain is far lower than the chance of a bee or wasp sting, or even a dog bite.
How to see fewer false widows at home
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01
Check window frames and corners
Look in window reveals, the top corners of rooms and conservatory frames for the tangled web and its tube retreat.
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02
Remove spiders humanely
Place a glass over the spider, slide a card underneath and release it outside, away from doors. The Natural History Museum's arachnid curator suggests leaving them in peace or moving them to a shed.
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03
Vacuum webs and egg sacs
Small, white, round egg sacs sit near the web. Vacuum them with the hose attachment and empty the vacuum outdoors.
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04
Seal the gaps
Fill cracks around window frames, cable entries and pipe holes with sealant, and brush webs out of window frames when you clean.
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05
Cut the food supply
Outdoor lights attract the insects false widows eat. Fit lights a little away from windows and doors and turn them off when not needed; use fly screens on windows you leave open.
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06
Keep clothes off the floor
Shake out clothes, towels and shoes left on the floor or outdoors, and pull bedding away from walls if you find spiders in a bedroom.
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07
Wear gloves outside
When clearing sheds, garden furniture, log piles or fences, wear gardening gloves.
When to call a professional
- You keep finding false widows in a baby's or child's bedroom, or someone in the home is frail or has a weakened immune system, and humane removal has not kept up.
- There are many webs high up on a façade, conservatory roof or stairwell that you cannot reach safely.
- You manage a school, care home or workplace and need a proper inspection.
Ask the company to identify the species first, to remove webs and egg sacs and seal entry points, and to explain any product it plans to use and where.
False widow spiders: frequently asked questions
Are false widows dangerous?
Rarely. Most bites cause pain like a wasp sting for a few hours. A small number cause stronger symptoms or become infected and need medical care.
What does a false widow bite look like?
A painful red spot, sometimes with swelling or a small blister. Watch for spreading redness, pus or an open sore, which need medical help.
How do I identify a noble false widow?
A shiny, round, brown abdomen with cream mottling and a pale crescent at the front, a very dark front body and a body of 7 to 14 mm.
Where do false widows live in the UK?
Mainly in southern Britain, spreading north. Indoors they favour window frames, high corners, kitchens and conservatories; outside, sheds, walls and fences.
Why are there more false widows in autumn?
Adult males wander indoors looking for females, mostly between July and November, so sightings rise in autumn.
Should I kill a false widow?
There is no need. Museum experts suggest leaving it alone or moving it outside with a glass and a card.
Can a false widow bite kill you?
The Natural History Museum says false widows are not the deadly spiders they are often thought to be. Infection of a bite wound is the main risk, so keep it clean.
What should I do if I am bitten by a false widow?
Wash the bite, apply a cold compress, take simple painkillers if needed and see a pharmacist, NHS 111 or 999 depending on how severe the symptoms are.
Sources
Museum, specialist society and NHS guidance, checked on 27 October 2026.
- Natural History Museum · How dangerous are false widow spiders? ↗Species in the UK, size, history, web height, favourite rooms, bite pain and duration, males wandering in autumn, number of UK spiders known to bite and humane removal.
- Natural History Museum · Identifying false widow spiders ↗Identification of each species, sizes, markings, where found, the Mediterranean false widow and look-alikes.
- British Arachnological Society · Noble false widow spider factsheet ↗Origin and spread, life history, web and habitat, how bites happen, symptoms, risk compared with stings and dog bites, media myths, imported black widows and removal with a glass and card.
- Dunbar et al. · Bites by the noble false widow spider Steatoda nobilis can induce Latrodectus-like symptoms (Clinical Toxicology) ↗Case series of 16 new confirmed bites, 24 in the literature, symptoms from mild to severe and hospital treatment in some cases.
- Dunbar et al. · Synanthropic spiders are reservoirs for medically important bacteria (Scientific Reports, 2020) ↗Bacteria, some antibiotic-resistant, found on noble false widows and their fangs.
- NHS · Insect bites and stings ↗Washing and cooling a bite, painkillers, signs of infection, when to see a pharmacist, use NHS 111 or call 999.
Spotted a shiny dark spider in the window frame?
Photograph it next to a coin, check the crescent and mottling against the table above and move it outside with a glass and a card.