No. Every black snake in South Carolina is non-venomous. The three you are likely to see — black racer, eastern ratsnake and eastern kingsnake — cannot hurt you, and all three are useful enough that you would rather they stayed.
One caveat worth knowing: an adult cottonmouth darkens with age until its banding almost disappears, so a dark snake at the water's edge that stands its ground deserves distance.
A quick note on the word, since it is the one people search. Snakes are venomous, not poisonous. Clemson draws the line neatly: venom is injected, by fangs or a sting, while poison has to be eaten, inhaled or touched — a poisonous mushroom, or poison ivy. No snake in South Carolina is poisonous. Six are venomous, and none of them is black.
The three black snakes you will actually see
Black racer
Slender, glossy, and among the most active snakes in the Southeast. Adults reach about four and a half feet, with smooth unpatterned scales and a white to grey chin and throat that is the easiest confirmation. They hunt by day rather than ambushing, and their instinct is to leave — fast.
Cornered, a racer will vibrate its tail, strike repeatedly and musk. It is bluff. In South Carolina populations, lizards and snakes make up over 85% of what they eat.
Eastern ratsnake
Heavier-bodied, three to five feet and sometimes over six. The build is described as loaf-shaped rather than round, and the scales are weakly keeled — each carries a slight ridge, where a racer's and a kingsnake's are smooth. The belly is checkered.
They are excellent climbers, so a black snake in a tree, a barn rafter or a soffit is usually this one. Their alarm response is unusual and diagnostic: they freeze in a rigid, kinked posture rather than fleeing. Adults eat mostly rodents, squirrels, birds and eggs.
Eastern kingsnake
Stout, averaging about three and a half feet, with smooth highly glossy scales — the genus name means "shining shield" — and a contrasting pattern of pale chain-like crosslines over black, with a black-and-white belly.
This is the one worth protecting. Kingsnakes eat other snakes, including copperheads and rattlesnakes, and carry a serum-based resistance to pit viper venom. They are also, relative to body size, among the most powerful constrictors measured — one study found kingsnakes generating substantially higher constriction pressures than ratsnakes.
Kingsnakes are frequently described as immune to snake venom. The literature says resistant — their blood serum inhibits pit viper venom, which is not the same as being unaffected by it. Worth getting right.
The two things that genuinely confuse people
1. Young black snakes are not black
Juvenile racers and juvenile ratsnakes are both boldly patterned — greyish with dark blotches — and they darken to solid black over their first year or two. A patterned young snake is the single most common copperhead misidentification in the region.
The test is where the pattern sits. A juvenile ratsnake's blotches run down the middle of the back and never extend to the sides. A copperhead's hourglass bands start at the flank and pinch in towards the spine. Opposite geometry.
There is a seasonal angle too. Juvenile ratsnakes look for somewhere warm to overwinter and often choose an attic, crawlspace or basement — while copperheads generally do not shelter in occupied buildings. So a patterned snake indoors in autumn is far more likely to be a harmless ratsnake.
2. An adult cottonmouth can read as black
This is the real one. Adult cottonmouths go dark olive, brown or nearly black, and the banding fades until it is faint or gone. At a glance, in poor light, that is "a black snake".
Behaviour separates them more reliably than colour. A cottonmouth will often stand its ground and gape, showing the white mouth lining it is named for. Harmless watersnakes and racers almost always flee — into the water if they can. If a dark snake near water holds position and opens its mouth at you, back away and treat it as venomous.
Why you want them around
The pest control case for black snakes is straightforward. NC State credits large eastern ratsnakes with feeding heavily on rodents and sparing farmers the cost of rodent control outright. Racers work through the lizard and snake population. Kingsnakes eat the venomous species you actually do not want.
A property with a resident kingsnake is a property doing something no product replicates.
What the law says
No South Carolina statute prohibits killing a common native snake — the protections in the wildlife code attach only to species the department has specifically designated, and across the entire regulation chapter the only snake listed is the southern hognose snake.
Two rules do apply to homeowners, though. Trapping snakes indoors is expressly permitted under § 50-11-2460(A)(5), which allows property owners or occupants to use commonly used traps to capture snakes, rats or mice in homes and businesses. But Regulation 123-151.3(A) prohibits transferring, selling or re-homing a native reptile outside a narrow list of exceptions — so passing a caught snake on to someone else is the step that gets people in trouble.
Relocating a snake a long distance is also a poor idea on its own merits. NC State notes that snakes hold distinct home ranges and that moving them significant distances raises their risk of dying.
General information taken from the published statute and regulation text, not legal advice. Confirm current requirements with SCDNR.
If one is in the house or the yard
- Identify it from a distance, or from a photograph. Never handle a snake to work out what it is.
- A harmless snake indoors can be swept out with a broom — NC State's own recommendation. Open a door and give it a direction.
- Never try to move a venomous snake yourself, whatever gloves or boots you are wearing.
- Then remove the reason it came. Snakes follow rodents. Clemson's line is that brush piles and stacked firewood attract snakes because they attract the rodents and insects snakes eat.
- Seal the way in — crawlspace vents, foundation cracks, gaps under doors.
Skip the repellent products. Clemson reports inconsistent results from snake repellents generally, and says liquid formulations give limited control while needing constant reapplication.
When to call
- You cannot identify it confidently and it is somewhere children or pets go.
- Snakes keep turning up — which nearly always means a rodent population is feeding them.
- They are getting into a crawlspace, garage or outbuilding you cannot seal yourself.
Our rodent control service covers South Carolina, North Carolina and Virginia, and for recurring snake sightings it is usually the actual fix — take away the food supply and the harborage. For the venomous species and what to do about a bite, see our full guide to snakes in South Carolina.
The short version
- No black snake in South Carolina is venomous. Racer, ratsnake and kingsnake are all harmless.
- Venomous, not poisonous — venom is injected; poison has to be eaten or touched.
- Young racers and ratsnakes are patterned, which is the usual copperhead mix-up. Their blotches stay in the middle of the back.
- Adult cottonmouths can look black. Near water, standing its ground and gaping means back away.
- Kingsnakes eat venomous snakes and resist their venom — the best free pest control on the property.
Further reading: the Savannah River Ecology Laboratory at the University of Georgia publishes free, non-commercial accounts of every snake in this region, with photographs — Snakes of South Carolina and Georgia (SREL Herpetology).
Frequently Asked Questions
No. Every black snake in South Carolina is non-venomous. The three you are likely to encounter are the black racer, the eastern ratsnake and the eastern kingsnake, and none of them is dangerous to people. Strictly speaking no snake is poisonous either: venom is injected, while poison has to be eaten, inhaled or touched.
Look at the scales and the build. A racer is slender with smooth glossy scales and a white to grey chin and throat, and it flees quickly in daylight. An eastern ratsnake is heavier, loaf-shaped rather than round, with weakly keeled scales that each carry a slight ridge, and a checkerboard belly. Ratsnakes climb well and freeze in a rigid kinked posture instead of running.
Yes, and this is the one genuine risk. Adult cottonmouths darken with age until the banding is faint or gone, so at a glance an adult can read as a plain dark snake. Behaviour is the more reliable guide: a cottonmouth often stands its ground and gapes to show the white mouth lining it is named for, whereas harmless watersnakes and racers almost always flee, usually into the water.
Juvenile black racers and juvenile eastern ratsnakes are both boldly blotched and darken to solid black over their first year or two. This is the most common copperhead misidentification in the region. The test is where the pattern sits: a juvenile ratsnake's blotches run down the centre of the back and never reach the sides, while a copperhead's hourglass bands start at the flank and pinch in toward the spine.
Yes. NC State credits large eastern ratsnakes with feeding heavily on rodents and sparing farmers the cost of rodent control. Black racers eat mostly lizards and other snakes, over 85% of stomach contents in South Carolina populations. Eastern kingsnakes eat venomous snakes including copperheads and rattlesnakes, and are resistant, though not immune, to pit viper venom.
No state law prohibits killing a common native snake. The only snake designated anywhere in the state wildlife regulations is the southern hognose snake. Two rules do affect homeowners: trapping snakes indoors is expressly permitted, but transferring, selling or re-homing a caught native reptile is prohibited outside a narrow list of exceptions. This is general information rather than legal advice.