Are There Black Widows in Montana?
No, black widows are not established in Montana and are extremely rare. The state's cool climate and cold winters are incompatible with black widow survival outdoors. An occasional specimen might arrive through cargo, but no breeding populations exist in the wild.
By Tim, founder of Easy Street Markets. I maintain the wildlife database and verify every animal and source myself. Updated July 22, 2026.
Northern Black Widow · Joseph McPhail CC BY
Western Black Widow · Rebecca Ray CC BY
Western Black Widow · Michael Eisen CC BY
- 1
- species recorded
- 80
- GBIF records
- September, August, October
- peak months
Yes, black widows are in Montana. Next you'll want:
Real sighting data, source iNaturalist
122 verified observations on iNaturalist of black widow have been recorded in Montana, most often in September, August, October.
When black widow are recorded in Montana
No, black widows are not established in Montana and are extremely rare. The state's cool climate and cold winters are incompatible with black widow survival outdoors. An occasional specimen might arrive through cargo, but no breeding populations exist in the wild.
Are they in Montana?
Black widows are not established in Montana and present essentially no risk to residents or visitors. The climate across Montana is too cold for black widows to thrive outdoors or establish populations. Montana's harsh winters, cool summers, and short growing season make it inhospitable for black spider survival. Temperatures in Montana regularly drop well below freezing in winter, making outdoor survival impossible. While a single black widow could theoretically arrive in a box from a warmer state, this is extraordinarily rare and would not result in a breeding population. Any black widow transported to Montana would struggle to survive winter outdoors or even in an unheated building. The nearest populations of established black widows are in Wyoming, southern Idaho, and parts of Colorado. Rest assured thatMontana wildlifeis black widow-free.
How dangerous is it?
Since black widows are not present in Montana, there is no danger from black widow bites in this state. For educational purposes, in warmer states where black widows are established, a bite is painful and can cause serious symptoms but is rarely fatal with modern medical care. The venom affects the nervous system and would cause muscle pain and cramping if a bite occurred in those regions. Symptoms typically develop within an hour and can last for several days even with treatment. Healthy adults bitten by a black widow in states where they are found generally recover well with supportive medical care. Antivenom is available in areas where black widows are present to manage severe cases. Children and elderly people face higher risks than healthy adults. Since Montana has no black widow population, residents have zero risk from this particular spider.
How to recognize one
While you are extremely unlikely to see a black widow in Montana, knowing how to identify one is useful for education and travel to warmer states. Female black widows are very distinctive and unmistakable with their appearance. They are shiny black with a round, walnut or grape-sized body and notably long legs relative to their body size. The most recognizable feature is a bright red or orange hourglass marking on the underside of the abdomen. Some females may have red spots on top of the body as well. Male black widows are much smaller, less glossy, and have red or white stripes rather than the classic hourglass pattern. Immature black widows may have more red or brown coloring before fully darkening to black. Black widows are not aggressive and will only bite if squeezed or pressed directly against skin. They prefer to remain hidden in their webs in dark, undisturbed spaces.
What to do if you are bitten or stung
If you believe you have been bitten by any spider in Montana, wash the bite area with soap and water and monitor for symptoms. Remove any rings or tight clothing from the affected limb in case of swelling. Keep the bitten area still and at or below heart level to reduce venom circulation if present. Apply a cool compress if you wish, though ice is not essential. Most spider bites in Montana cause only local redness and minor swelling that resolve without treatment. Seek medical care if you have severe pain, significant swelling, or signs of infection developing. This is general information, not medical advice; if you are bitten, call Poison Control at 1-800-222-1222, or 911 if symptoms are severe. Since black widows are not present in Montana, the chance of a black widow bite is essentially zero. Other spiders do live in Montana and can bite if directly disturbed, but such bites are very mild.
How to prevent encounters in this state
Since black widows do not live in Montana, prevention specific to black widows is not necessary. However, general spider safety practices apply. Keep your home clean and reduce clutter in basements, attics, and storage areas where spiders might hide. Wear gloves when handling stored items, firewood, or gardening supplies, which may contain various harmless spider species. Shake out shoes and clothing that have been stored in closed spaces before putting them on. Seal cracks and gaps around doors and windows to reduce the number of spiders and insects entering your home. Check dark corners and storage areas periodically for spiders if you wish to maintain a spider-free home. When camping or hiking in Montana's forests and mountains, check your tent and sleeping bag for spiders before settling in for the night. Most spiders found in your tent or sleeping bag are completely harmless.
Where in Montana and when
Black widows do not occur in Montana due to the state's cold climate, so there are no specific regions or seasons to be concerned about. Montana's temperature year-round is incompatible with black widow survival. Winter temperatures throughout Montana regularly drop well below freezing, far too cold for a warm-weather spider to survive. Even summer temperatures in most Montana areas are generally too cool for black widow reproduction and population establishment. The southern parts of Montana are slightly warmer than the north, but even these areas remain unsuitable for black widows. Higher elevations in the Rocky Mountains and surrounding areas are even colder and more inhospitable to warm-weather spiders. Montana's short growing season means that even on the warmest summer days, temperatures cool significantly at night. If you travel from Montana to southern states like Arizona or Texas during warm months, you may encounter a black widow. All ofMontana's parks and wildlifeare black widow-free year-round.
Harmless lookalikes
If you find a black or dark-colored spider in Montana, it is not a black widow. Nearly all spiders found in Montana are brown, gray, or tan colored, not black. Jumping spiders are common and harmless throughout Montana. They are small and stocky with large forward-facing eyes and good vision. Wolf spiders are fast, dark brown or gray hunters and are beneficial predators that control pest insects. Cellar spiders are pale and have very long, thin legs. House spiders come in brown shades and build cobwebs in corners. Fishing spiders near Montana water are large and dark but lack the hourglass marking. Montana's spider diversity is rich and nearly entirely beneficial. Spiders help control mosquitoes, flies, and other pests throughout the state. Seeour wildlife guidesfor more identification help.
Frequently Asked Questions
Are black widows found in Montana? No, black widows do not live in Montana. SeeMontana wildlifeinformation for the spiders that do live here. Should I worry about black widow bites? There is no reason to worry about black widow bites in Montana. Black widows are not present, so bites do not occur. What spiders should I be cautious about? Most Montana spiders are harmless. No spiders in the state pose a serious threat. Learn aboutMontana wildlifeto identify common spiders. Can a black widow survive in Montana? A single black widow might survive indoors if transported from a warm state, but it cannot reproduce or establish a population in Montana. Visitour wildlife guidesfor more information.
Plan your trip
Best time to see black widow in Montana: September, August, October
See the month-by-month sighting calendar.
Plan your black widow sighting in Montana
80 verified black widow records have been logged in Montana. See the GBIF records.
Where to look in Montana
- Big Hole National Battlefield · Wildlife Watching, Birdwatching · Find hotels
- Bighorn Canyon National Recreation Area · Wildlife Watching, Birdwatching · Find hotels
- Grant-Kohrs Ranch National Historic Site · Wildlife Watching, Birdwatching · Find hotels
- Lewis & Clark National Historic Trail · Wildlife Watching · Find hotels
- Nez Perce National Historical Park · Wildlife Watching, Birdwatching · Find hotels
- Yellowstone National Park · Wildlife Watching, Birdwatching · Find hotels
Frequently asked questions
Are they in Montana?+
Black widows are not established in Montana and present essentially no risk to residents or visitors. The climate across Montana is too cold for black widows to thrive outdoors or establish populations. Montana's harsh winters, cool summers, and short growing season make it inhospitable for black spider survival. Temperatures in Montana regularly drop well below freezing in winter, making outdoor survival impossible. While a single black widow could theoretically arrive in a box from a warmer state, this is extraordinarily rare and would not result in a breeding population. Any black widow transported to Montana would struggle to survive winter outdoors or even in an unheated building. The nearest populations of established black widows are in Wyoming, southern Idaho, and parts of Colorado. Rest assured thatMontana wildlifeis black widow-free.
How dangerous is it?+
Since black widows are not present in Montana, there is no danger from black widow bites in this state. For educational purposes, in warmer states where black widows are established, a bite is painful and can cause serious symptoms but is rarely fatal with modern medical care. The venom affects the nervous system and would cause muscle pain and cramping if a bite occurred in those regions. Symptoms typically develop within an hour and can last for several days even with treatment. Healthy adults bitten by a black widow in states where they are found generally recover well with supportive medical care. Antivenom is available in areas where black widows are present to manage severe cases. Children and elderly people face higher risks than healthy adults. Since Montana has no black widow population, residents have zero risk from this particular spider.
More places to see black widow
More wildlife in Montana