Snakes in Illinois: Identification Guide

Learn to identify all 40 snake species in Illinois, including venomous copperheads, cottonmouths, and rattlesnakes. Includes a comparison of snake-themed t-shirts for snake fans.

The Short Answer: Illinois is home to roughly 40 snake species, only four of which are venomous: the copperhead, cottonmouth (water moccasin), timber rattlesnake, and massasauga rattlesnake. Non-venomous species include the common garter snake, eastern rat snake, and milksnake. Use this guide to identify snakes in Illinois by color, pattern, and habitat.

What snakes are found in Illinois?

Illinois has about 40 snake species. The venomous ones are pit vipers with heat-sensing pits. Non-venomous species include the eastern garter snake, northern water snake, eastern rat snake, milksnake, and Dekay's brownsnake. A full list can be found in our Illinois snake identification guide.

How to identify venomous snakes in Illinois?

Venomous snakes in Illinois have a triangular head, elliptical pupils, and a heat-sensing pit between the eye and nostril. The copperhead has an hourglass pattern, the cottonmouth is thick and dark, the timber rattlesnake has black chevrons on yellow or brown, and the massasauga has dark blotches on gray. Non-venomous snakes have round pupils and narrow heads.

What are the most common non-venomous snakes in Illinois?

The most common non-venomous snakes are the eastern garter snake (with three light stripes), the northern water snake (dark with bands that fade), the eastern rat snake (black with a white chin), the milksnake (with red, black, and yellow bands), and Dekay's brownsnake (small and brown with a light stripe). These are often mistaken for venomous species, but they are harmless.

Where do Illinois snakes live?

Snakes in Illinois inhabit forests, grasslands, wetlands, and rocky bluffs. The cottonmouth is found near water in the southern part of the state. Rattlesnakes prefer wooded areas and hillsides. Many non-venomous snakes live in yards and gardens. For more on reptile habitats, see our reptile category.

When are snakes most active in Illinois?

Snakes are active from April to October. They are most active during warm weather, especially in the early morning and late afternoon. In winter, they hibernate in dens called hibernacula.

Show Your Snake Pride with These T-Shirts

After learning to identify Illinois snakes, you might want to show off your interest. These snake t-shirts are great for wearing on hikes or to reptile events. Check out our full collection of snake t-shirts.

ProductPriceDescription
Rattlesnake Graphic T-Shirt$16.99Features a rattlesnake graphic
Green Viper Snake T-Shirt$26.95Green viper design
Retro Cute Snake T-Shirt$12.99Retro cute snake design
Snake T-Shirt$26.95Simple snake graphic
Funny Snake T-Shirt$21.79Humorous snake design
Just A Boy Who Loves Snakes T-Shirt$9.99For young snake fans
Men's Snake T-Shirt$19.30"It's Venomous not Poisonous" text
Snake Shirt. Snake Lover Gift. Snake T-Shirt. Snake Owner Gift. Snake Lover Shirt. Reptile Lover Shirt. Snake Apparel. Snake Theme #OS5638$16.93Multiple snake designs
Funny Cobra Lover King Snake Cobra T-Shirt$13.38Funny cobra graphic
Cobra Gift Venomous Reptile Accessories & Stuff Funny Cobra Design for Men Women Kids King Snake Cobra Lover T-Shirt OEKO-TEX STANDARD 100$18.69Funny cobra design, OEKO-TEX certified
Motor City DesignWorx Vintage Distressed King Cobra Power Snake Muscle Car Karate T-Shirt OEKO-TEX STANDARD 100$14.99Vintage king cobra design
Urban Empyre Cobra Snake x King Cobra Snake Serpent T-Shirt$13.49Cobra and king cobra graphic
King Cobra Vintage Snake Gifts King Cobra Groovy Vintage Snake T-Shirt$19.99Groovy vintage cobra
Mara Closet Vintage Snake Japanese Style King Cobra T-Shirt$15.95Japanese style king cobra
Magical and Funny Snake lover Gifts King Cobra Snake T-Shirt$14.44Magical cobra design

Rattlesnake Graphic T-Shirt

Rattlesnake Graphic T-Shirt This t-shirt features a bold rattlesnake design perfect for anyone who appreciates these iconic Illinois venomous snakes. The graphic is detailed and the shirt is comfortable for everyday wear. Check Price and Availability

Green Viper Snake T-Shirt

Green Viper Snake T-Shirt A vivid green viper design that stands out. Great for snake lovers who want a pop of color. The fabric is soft and the fit is true to size. Check Price and Availability

Retro Cute Snake T-Shirt

Retro Cute Snake T-Shirt A charming retro design that makes snakes look friendly and approachable. Good for kids or anyone who likes cute animal graphics. Check Price and Availability

Snake T-Shirt

Snake T-Shirt A straightforward snake graphic that lets the animal speak for itself. Simple and effective for everyday wear. Check Price and Availability

Funny Snake T-Shirt

Funny Snake T-Shirt A humorous take on snakes, sure to get a laugh. Great for casual outings or reptile conventions. Check Price and Availability

Just A Boy Who Loves Snakes T-Shirt

Just A Boy Who Loves Snakes T-Shirt A sweet shirt for young snake fans. Inexpensive and fun, it shows off a love for serpents. Check Price and Availability

Men's Snake T-Shirt

Men's Snake T-Shirt This shirt says "It's Venomous not Poisonous" and features a snake design. Good for educated snake owners. It comes in black and is available in men's sizes. Check Price and Availability

Snake Shirt. Snake Lover Gift. Snake T-Shirt. Snake Owner Gift. Snake Lover Shirt. Reptile Lover Shirt. Snake Apparel. Snake Theme #OS5638

Snake Shirt. Snake Lover Gift. Snake T-Shirt. Snake Owner Gift. Snake Lover Shirt. Reptile Lover Shirt. Snake Apparel. Snake Theme #OS5638 A multi-themed shirt with various snake designs, perfect for gifting. The fabric is comfortable and the print holds up well. Check Price and Availability

Funny Cobra Lover King Snake Cobra T-Shirt

Funny Cobra Lover King Snake Cobra T-Shirt A funny cobra design that appeals to snake fans. Lightweight and good for warm weather. Check Price and Availability

Cobra Gift Venomous Reptile Accessories & Stuff Funny Cobra Design for Men Women Kids King Snake Cobra Lover T-Shirt OEKO-TEX STANDARD 100

Cobra Gift Venomous Reptile Accessories & Stuff Funny Cobra Design for Men Women Kids King Snake Cobra Lover T-Shirt OEKO-TEX STANDARD 100 An OEKO-TEX certified shirt with a funny cobra graphic. Safe for sensitive skin and machine washable. Check Price and Availability

Motor City DesignWorx Vintage Distressed King Cobra Power Snake Muscle Car Karate T-Shirt OEKO-TEX STANDARD 100

Motor City DesignWorx Vintage Distressed King Cobra Power Snake Muscle Car Karate T-Shirt OEKO-TEX STANDARD 100 A vintage distressed king cobra design that also features muscle car and karate elements. Unique and eye-catching. Check Price and Availability

Urban Empyre Cobra Snake x King Cobra Snake Serpent T-Shirt

Urban Empyre Cobra Snake x King Cobra Snake Serpent T-Shirt A modern cobra and king cobra graphic with a serpent theme. Fits well and has a nice weight. Check Price and Availability

King Cobra Vintage Snake Gifts King Cobra Groovy Vintage Snake T-Shirt

King Cobra Vintage Snake Gifts King Cobra Groovy Vintage Snake T-Shirt A groovy vintage cobra design that brings back retro vibes. Good for casual wear or themed events. Check Price and Availability

Mara Closet Vintage Snake Japanese Style King Cobra T-Shirt

Mara Closet Vintage Snake Japanese Style King Cobra T-Shirt A Japanese style king cobra design with vintage feel. Great for those who appreciate Asian art and snakes. Check Price and Availability

Magical and Funny Snake lover Gifts King Cobra Snake T-Shirt

Magical and Funny Snake lover Gifts King Cobra Snake T-Shirt A magical and funny cobra design that makes a great gift. The shirt is comfortable and the colors are bright. Check Price and Availability

Frequently Asked Questions

How can you tell a copperhead from a milksnake?

Copperheads have hourglass-shaped bands that are darker on the edges, while milksnakes have red, black, and yellow bands that go all the way around the body. Copperheads have a triangular head and vertical pupils; milksnakes have round pupils and a narrower head.

What should I do if I see a venomous snake in Illinois?

Stay calm and back away slowly. Give the snake plenty of space. Do not try to handle or kill it. Most bites occur when people attempt to move or harm the snake. Contact local animal control if it is near your home.

Are there any protected snake species in Illinois?

Yes, the massasauga rattlesnake is state-endangered and the copperhead is state-threatened. It is illegal to kill or capture these species without a permit.

Do snakes in Illinois hibernate?

Yes, snakes brumate (a form of hibernation) during winter. They gather in dens called hibernacula, often in rocky crevices or mammal burrows, and emerge in spring.

Can I keep an Illinois snake as a pet?

Most non-venomous snakes can be kept as pets, but you should check local laws. It is illegal to capture venomous snakes from the wild. Adopting from a reputable breeder is recommended.

For more information, visit our Illinois snake identification guide or browse snake t-shirts.