Are Daddy Long Legs Poisonous?

Daddy long-legs are not poisonous. That is the short answer, and it is one of the most persistent myths in pest control. Despite decades of rumors claiming these creatures carry deadly venom, science tells a very different story.

At Bigfoot Pest Management, we hear this question more than almost any other. Below, we break down what daddy long-legs actually are, where the myth came from, and what to do if you are seeing them around your Washington home.

What Are “Daddy Long Legs”?

The confusion around daddy long-legs starts with one simple problem: three completely different creatures share that name.

• Harvestmen are the most commonly misidentified. They are arachnids, but they are not spiders. They have one fused body segment instead of two, only two eyes, and no silk glands or venom glands. They cannot bite.
• Cellar spiders are true spiders with eight eyes, two body segments, and wispy, tangled webs in corners and basements. They do have small venom glands, but their venom is weak and rarely causes any reaction in humans.
• Crane flies look like giant mosquitoes with extra-long legs. They are insects, not arachnids, and most adult crane flies have no mouthparts capable of biting at all.

Are Daddy Long-Legs Poisonous or Venomous?

No. Neither harvestmen nor cellar spiders pose any poison or venom risk to humans.

A quick clarification on terms: poisonous means harmful when touched or eaten. Venomous means the creature injects toxins through a bite or sting. These are different things, and most people use them interchangeably when they mean venomous.

Harvestmen are sometimes called “poisonous” because they produce a foul-smelling defensive chemical that deters predators. That chemical is a type of poison, but it is not toxic to humans and cannot be injected. Harvestmen have no fangs and no venom glands whatsoever.

Cellar spiders do have venom, but research shows it is extremely weak. A 2019 peer-reviewed study on Pholcid venom (PubMed Central) confirmed that cellar spider venom is far less potent than that of a black widow or brown recluse. It poses no medically significant risk to people.

Where Did the “Most Venomous Spider” Myth Come From?

One popular claim insists daddy long-legs are the most venomous spiders in the world, held back only by fangs too small to pierce human skin. This story has circulated for decades, appearing in classrooms, on TV, and across the internet.

Entomologists at the University of California, Riverside addressed this myth directly. There is no scientific evidence to support it. The claim has never appeared in peer-reviewed literature. Harvestmen, the creatures most often referenced in this myth, do not have venom at all.

The myth persists partly because cellar spiders and harvestmen are so often confused. When someone sees a cellar spider and hears the “deadly venom” story, the idea sticks.

Can Daddy Long-Legs Bite You?

Harvestmen cannot bite. They have no fangs.

Cellar spiders technically can bite, but it is uncommon, and the bite is mild. Their fangs are small and generally not built for piercing thicker mammalian skin.

If a bite occurs, it typically produces minor redness or a small welt, similar to a mosquito bite, and resolves on its own.

Neither type of daddy long-legs is considered medically significant to humans.

Are Daddy Long-Legs Helpful in Your Home?

Both harvestmen and cellar spiders have benefits. Harvestmen are scavengers that feed on decomposing organic matter, small insects, and mites. They do not build webs and stay close to the ground.

Cellar spiders actively hunt and eat small insects. They catch flies, mosquitoes, ants, and even other spiders. If you prefer a low-impact approach to pest control, our guide to effective spider control walks through options for keeping populations in check.

That said, a growing number of cellar spiders often means insects are present to feed them. If webs are building up in your basement or garage, it may be a sign of a larger pest population worth investigating.

How to Get Rid of Daddy Long-Legs

If you would rather not have daddy long-legs inside, a few simple steps can help.

Physical removal: Place a glass or jar over the spider or harvestman, slide a piece of paper underneath, and carry it outside. No chemicals needed.

Prevention tips:

• Seal cracks around windows, doors, and foundation gaps
• Use yellow bug lights outdoors, which attract fewer insects and the things that eat them
• Run a dehumidifier in crawl spaces and basements to reduce moisture
• Clear clutter and storage boxes from corners to limit hiding spots
• Sweep down old webs each season so cellar spiders do not establish permanent residence

If you are seeing cellar spiders in several areas of your home, our guide to identifying big house spiders can help you figure out what you are dealing with before deciding on the next steps.

Related Questions to Explore

What attracts spiders and other pests into a home?
Spiders are primarily drawn indoors in search of food. An influx of spider activity often points to an underlying issue with common prey insects, such as ants, cockroaches, or flies, multiplying inside your living spaces.

How do seasonal weather changes affect indoor pest activity?
As seasons shift, many pests look for shelter from extreme temperatures. While spiders are active year-round, overwintering pests like stink bugs and stinging insects frequently invade homes in the autumn, looking for warmth, making proactive pest prevention essential.

When does a minor pest issue require professional treatment?
Occasional invaders like daddy long-legs can usually be managed with basic sweeping or exclusion tactics. However, fast-multiplying pests like fleas, deeply entrenched ant colonies, or structural nuisances like rodents typically require targeted intervention to be completely eliminated.

When to Call a Pest Control Professional

A few daddy long-legs here and there are not cause for concern. Some situations do warrant a call:

• You are finding clusters of cellar spiders in multiple rooms or areas
• Egg sacs are visible near webs, a sign that the population is growing
• You are also seeing other insects, which can indicate a food source drawing spiders in
• You have tried prevention steps, and the population keeps returning
• You want a professional assessment to rule out other spider species that require attention, such as black widows or hobo spiders

Bigfoot Pest Management offers no-pressure inspections for homeowners throughout the service area. If you are not sure what you are dealing with, our team can identify the species, assess whether there is an underlying pest issue, and recommend the right approach without overselling treatment you do not need.

Learn more about our spider control services and what to expect from an inspection.

Conclusion

Daddy long-legs are not poisonous, and they are not venomous in any way that matters to humans.

The myth has been around for decades, but it does not hold up under scrutiny. Whether you are looking at a harvestman on your porch or a cellar spider in the corner of your basement, neither one poses a threat to your family.

If you want them gone, the steps are simple. And if the spider count is climbing or you are seeing signs of a larger pest issue, Bigfoot Pest Management is here to help.

Schedule a no-pressure inspection, and we will give you a straight answer on what is going on.