The fastest way to get rid of spider eggs is to physically remove the egg sac with a vacuum or scrape it off the surface and seal it in a bag for outdoor disposal. A single egg sac can contain anywhere from 4 to 600 eggs depending on the species, so acting quickly before they hatch prevents a small problem from becoming a much bigger one.
What Spider Egg Sacs Look Like
Spider egg sacs come in a wide range of shapes, sizes, and colors, but most share a few common features. They’re typically small silk pouches, often round or teardrop-shaped, with a texture that looks papery, cottony, or slightly fuzzy. Colors range from pearly white to green, brown, or russet. Many sacs found in sheltered spots look like little cotton balls with soft, indistinct edges.
You’ll usually find them tucked into corners, behind furniture, along baseboards, inside storage boxes, or in undisturbed areas like garages and crawl spaces. Outdoor sacs are often camouflaged with bits of leaf debris. Some species carry their egg sacs with them (wolf spiders drag theirs attached to their body), while others attach sacs to webs or flat surfaces. If you spot one that’s already open or torn, spiderlings may have already dispersed into your home.
One sac worth recognizing specifically: the brown widow spider produces an egg sac covered in small spiky projections, sometimes described as looking like a spiny pollen grain. It’s distinctive enough that it’s easy to identify once you know what to look for. Most other species produce smooth or loosely woven sacs that are harder to tell apart.
Physical Removal: The Most Reliable Method
Vacuuming is the simplest and most effective approach. Use a hose attachment to suck up the egg sac directly, then immediately remove the vacuum bag or empty the canister into a sealed plastic bag and dispose of it in an outdoor trash bin. If you leave the sac sitting in the vacuum, eggs can still hatch inside.
For sacs attached to walls, ceilings, or other hard surfaces, you can scrape them off with a stiff piece of cardboard, a putty knife, or even a paper towel. Drop the sac into a sealed bag or container right away. If you’re concerned about the species, wear gloves and avoid crushing the sac with bare hands, since some sacs may have a guarding mother spider nearby.
Flushing a removed egg sac down the toilet or submerging it in soapy water also works. The goal is containment: don’t leave a removed sac sitting in an open trash can indoors where spiderlings could still emerge.
Why Most Sprays Don’t Work on Egg Sacs
Here’s something most people don’t realize: standard bug sprays are largely ineffective against spider egg sacs. Research from the University of California, Riverside found that spider egg sacs are constructed with highly water-repellent silk. Water-based pesticide sprays simply bead up on the surface and never reach the eggs inside.
Oil-based aerosol pesticides, however, can penetrate the silk layer and kill the contents. In testing on brown widow egg sacs, oil-based products provided complete prevention of spider emergence, while water-based sprays fell far short. If you want a chemical option, look for oil-based aerosol insecticides rather than the typical pump sprays. But even then, physical removal is faster and more certain since you’re eliminating the sac entirely rather than hoping a spray penetrated it.
Where to Check for Hidden Egg Sacs
Spiders lay eggs in quiet, undisturbed spots, so the places you clean least often are the places most likely to have egg sacs. A thorough sweep of your home should cover:
- Corners and ceiling joints in rooms that don’t get much traffic
- Behind and under furniture that rarely gets moved, especially bookshelves, dressers, and bed frames
- Storage areas like closets, attics, basements, and garages, particularly inside cardboard boxes
- Window frames and door frames on both the interior and exterior sides
- Along baseboards in less-used rooms
- Outdoor structures near the house, including porch overhangs, eaves, outdoor furniture, and garden sheds
If you’ve already found one egg sac, check the immediate area carefully. Some species produce multiple sacs in close proximity.
Preventing Spiders From Laying Eggs Indoors
Removing the egg sacs you can see solves the immediate problem, but preventing new ones takes a few longer-term steps. Spiders come inside looking for food (other insects), shelter, and moisture. Reducing all three makes your home far less attractive.
Seal cracks and gaps around doors, windows, and your foundation. Even small openings along utility pipes or cable entry points are enough for a spider to squeeze through. Weather stripping and door sweeps close off the most common entry routes.
Reduce clutter, especially in storage areas. Spiders love undisturbed piles of boxes, clothing, or old newspapers because they provide perfect cover for web-building and egg-laying. Switching from cardboard boxes to sealed plastic bins eliminates a favorite hiding spot. Regular cleaning and web removal also discourages spiders from settling in, since they’ll relocate if their webs keep getting destroyed.
Control moisture by fixing leaky pipes and using a dehumidifier in damp basements or crawl spaces. Many insects that spiders feed on are drawn to moisture, so drying out your home cuts off the food supply. Outside, trim bushes and vegetation back from your foundation so spiders don’t have a convenient staging ground right next to your walls.
When an Infestation Needs Professional Help
A single egg sac in a garage corner is a normal find that you can handle yourself. The situation changes when you’re finding spiders regularly across multiple rooms, discovering several egg sacs (especially opened ones), or dealing with a species you can’t identify. An already-hatched sac means the problem has progressed beyond what a single cleanup session will fix, since hundreds of spiderlings may have dispersed throughout your home.
Professional pest control is also worth considering if you’ve tried store-bought products and the spiders keep coming back, or if you have young children or pets and aren’t sure whether the spiders are a medically significant species. Pest control technicians can identify the species, locate hidden nesting sites you might miss, and apply targeted treatments that reach egg sacs more effectively than consumer-grade products.