Even if you don’t have arachnophobia, spiders can still become a nuisance. Full-blown infestations can happen if arachnid populations are left unchecked.

One of the best solutions is using pesticides to kill spiders. The best insecticide for spiders is available in a variety of delivery systems discussed below:
- Ortho Home Defense MAX Insect Killer Spray
- Bayer Advanced Complete Insect Killer for Soil and Turf
- Hot Shot Indoor Pest Control Fogger
- TERRO Spider Killer Aerosol Spray
- Syngenta Demand Cs
Spider Insecticides
Arachnid infestations are a nuisance at best but can be dangerous with some species. Using insecticides designed to kill spiders is an effective control method, and using these pesticides properly can help to prevent mass infestations of spiders that will require professional pest control.
Insecticides are made from a variety of chemical compounds that attack spiders or other insects through specific pathways. All pesticides are regulated, and it is important that you follow the manufacturer’s instructions completely in order to avoid potential health hazards. Remember, once your pesticide treatment has begun, there are steps you can take to aid in its effectiveness.
How Insecticides For Spiders Are Applied
Pesticides that are designed to kill arachnids can be applied in several different ways. These insecticides can kill through direct contact with the spiders or through indirect contact on surfaces that spiders crawl across.
Best Insecticide for Spiders Outdoors
Outdoor Spider Spray Pesticides: A spider spray can come in either an aerosol can or may be used in a canister with a pump and nozzle system. These insecticides for spiders can be applied directly on arachnids and their webs to kill them, or the pesticide can be sprayed on a surface where spiders are gathered or are likely to roam.
While some of these pesticides are designed to kill spiders, many are effective at eliminating all arachnids, including scorpions. Remember that in outdoor settings, these insecticides may affect more than spiders; the pesticides may also prove dangerous to other animals.
Outdoor Insecticide Granules For Spiders: For outdoor treatments, pesticide powders or granules can be applied to lawns or next to building foundations. These insecticides are effective against ground spiders, who forage for prey. These type of insecticides are less effective against web-building spiders.
Fogger Insecticides For Spiders: “Bug Bombs” or “Foggers” contain pesticides that are released by aerosol and are intended to cover larger areas with insecticides indoors, like attics or basements. Pesticide foggers for spiders have the advantage of covering places that spider sprays struggle to reach, as well as penetrating into cracks and other areas that spiders like to hide.
Indoor Specific Spider Insecticide
Indoor Spider Spray: Pesticides that target spiders indoors are available in aerosol or concentrates. Many of these insecticides will kill spiders with direct contact but can also be used for indirect contact on interior surfaces like baseboards and crevices. Remember that indoor spider sprays can prove harmful to family members and pets if directions are not followed.
In this video, a professional pest controller demonstrates spraying using both an aerosol can and a hand sprayer, applying insecticides in areas spiders are found.

How Often Do Pesticides For Spiders Need To Be Used?
Insecticides designed to kill spiders are often referred to as “Hot,” meaning that these products are intended to be sprayed directly onto the arachnids for the best results. Hot insecticides can be used anytime that spiders make an appearance. However, the best insecticide for spiders is able to kill arachnids indirectly by covering surfaces that spiders will come into contact with as well.
Many spray pesticides used to kill spiders are designed to cover areas where arachnids like to gather or roam and will act as a repellant as well as a killer compound. Insecticides intended to be used inside of the home will last two or more weeks before they break down. Outdoor pesticides can last a month or more before they lose their ability to effect spiders.
Granule pesticides designed for arachnids will often require activation before they begin working. They must be sprayed down with water, for example, in order to release the insecticides. The best insecticides for spiders in this form will six to eight weeks before they break down (pesticides that are micro-encapsulated will last much longer).
Insecticide foggers designed to kill spiders are most effective as direct contact products. They perform best against arachnids for the first 24-hours, with limited abilities to kill spiders for up to a week after the pesticide “bomb” is used.
Using Insecticides For Spiders Safely
There is no getting around it, pesticides used to kill arachnids do pose potential health risks. It is important to follow the manufacturer’s instructions when using these insecticides to eliminate spiders at your home. The best insecticides for spiders use formulas that last long after they are applied, so caution must be exercised around children and pets.
Reviews Of Insecticides For Spiders
Ortho Home Defense MAX Insect Killer Spray
A pesticide for spiders that works both indoors and outdoors.

The Home Defense MAX is an effective insecticide against a multitude of insects that are known to infest properties. It comes in a gallon container, allowing it to cover large areas with a single purchase. This insecticide comes with a spray nozzle, allowing it to be applied directly from the container.
It can be used both indoors as well as outside. This insecticide can last for up to a year, providing a long-term barrier against spiders.

The manufacturer suggests that the product is safe to be around once it has dried.
Pros
- The insecticide is odor-free
- It works on over 130 types of insects
- Acts as an insecticide and repellent for up to 12-months
Cons
- Its spray nozzle can leak insecticide onto the user’s hands
- The insecticide’s duration is 75-percent shorter outdoors
Bayer Advanced Complete Insect Killer for Soil and Turf
An outdoor pesticide for use on spiders who ground forage.

The insecticide used in these granules are encapsulated, allowing it to kill and repel spiders for a longer period of time. Once the formula is sprayed down and dried, it can be safe for children and pets to walk on.
Not only does the insecticide kill arachnids, but it is also effective against over fifty insect species. This product will penetrate the soil as well as sit on the surface.
A 10-pound bag is able to treat up to 5000 square feet of outdoor property.
Pros
- It can be used both as a lawn treatment and foundation barrier
- This product will affect spiders for up to three months
- The pesticide will kill arachnids infesting lawns within 24-hours
Cons
- The insecticide must be watered to activate
- This product has limited effectiveness against web-building spiders
Hot Shot Indoor Pest Control Fogger
An aerosol-based pesticide for spiders in hard to reach places.

Hot Shot includes four foggers in this pack, allowing you to destroy spiders in several rooms at once. While it cannot be used in spaces under five feet square, each canister can cover up to 2000 square feet.
The stand-out feature for this product is its ability to cover areas that spiders will frequent but are hard to access. It works on other insects besides spiders as well.
This pesticide does require preparation before it is used, but is easy to set up and activate. It can protect against spiders for weeks after release.
Pros
- This insecticide kills spiders and other insects quickly
- It penetrates into cracks and other hard to reach places
- The pesticide does not leave a smell or residue
Cons
- Using this insecticide requires a lot of preparation
- The property must be vacated during use
TERRO Spider Killer Aerosol Spray
A fast and easy to use indoor or outdoor spider spray.
No products found.Terro’s aerosol spray is a contact killer that can be sprayed directly onto spiders. It has a residual effect, making it useful for spraying in locations where spiders may travel, such as baseboards or walls behind furniture.
This product has a water-based formula, a feature that makes it less likely to leave residue or stains on objects. It can also work on other insects including ants, bedbugs, and German cockroaches.
It is easy to use and can be applied on any non-food surface. When used outdoors, it is best applied in windless conditions.
Pros
- It can kill spiders on contact
- This insecticide can be sprayed on surfaces as a contact killer and barrier
- The product will also work on other pesky insects
Cons
- Build-up on the nozzle can drip onto a user’s hand when spraying
- Aerosol can insecticide products run out quickly
Syngenta Demand Cs
A concentrate used for spiders living on grass and plants.

Syngenta’s concentrate comes in an eight-ounce bottle with a squeeze-activated measuring compartment, helping you to measure the correct amount before it leaves the bottle.
The active ingredient is capsuled, allowing it to last up to four months between treatments once activated. An additional feature of this covering is that it prevents more serious interactions with the skin in the event of accidental contact.
The insecticide is effective against an array of insects, including some flying species like mosquitos that other products may not affect. Each bottle can cover up to one acre.
Pros
- This product can make up to 100 gallons of insecticide
- It can last up to four months after it is applied
- The pesticide can be used on mosquitos and wasps as well as arachnids
Cons
- This concentrate must be mixed before it can be used
- It has a high price point for the amount received
Which One Is Best?
While all of the products reviewed offer great features, the Ortho Home Defense Insect Killer for Indoor and Perimeter2, Controls Ants, Roaches, Spiders and More, 1 gal stands out as the best insecticide for spiders. First off, the product is easy to use thanks to the nozzle sprayer and hose included with the bottle. Another feature that stands out from some of the others is that it can be used indoors as well as outside.
- Ortho Home Defense Insect Killer for Indoor & Perimeter2 kills the toughest home-invading insects, including ants, cockroaches, spiders, fleas, ticks, scorpions, earwigs, silverfish and periodical cicadas (as listed)
- This insect killer spray provides a long-lasting bug barrier of up to 12 month protection against ants, roaches and spiders indoors on non-porous surfaces
- Use this pest control spray indoors in kitchens and bathrooms or around doors and windows, and outdoors to the perimeter of foundations, patios, decks, garages or wherever insects are a recurring problem
- Apply this bug killer anytime as a preventative treatment or after you see evidence of insect activity
- This 1 gal. container of Ortho Home Defense Insect Killer for Indoor & Perimeter2 comes with convenient trigger sprayer for easy application
While it can be sprayed directly onto spiders as a contact killer, this product offers extended protection once applied. It lasts up to three months outdoors, and up to a year inside. The one-gallon bottle is pre-mixed but will cover a large amount of space before it runs out.
This formula is not only effective against spiders, but it can also kill over 130 insects. That not only eliminates a lot of common household pests, it also means that many of the bugs and flying insects that spiders use as a food source can be eliminated. Removing their food supply will cause remaining spiders to move elsewhere.
Finally, detailed instructions are provided for maximum safety!