A big red ant with wings is almost always a reproductive ant, called an alate, that has left its colony to mate and start a new nest. The most likely culprit is a red carpenter ant, one of the largest ant species in the United States, with winged individuals reaching half an inch or more in length. But depending on where you live, you could also be looking at a fire ant swarmer, a harvester ant, or something that isn’t actually an ant at all.
Most Likely: Red Carpenter Ants
Several species of carpenter ant range in color from reddish-brown to deep red and black. The red carpenter ant (Camponotus chromaiodes) and the closely related Camponotus castaneus are among the most common large red ants in the eastern U.S. They’re roughly the same size as the well-known black carpenter ant, often 6 to 13 millimeters for workers and even larger for the winged reproductive forms. When you see one with wings, it’s either a virgin queen or a male drone preparing for a mating flight.
Carpenter ants nest inside wood, but they don’t eat it the way termites do. They chew smooth tunnels and galleries to house their colony, pushing sawdust-like shavings (called frass) out of small openings. This nesting behavior can damage structures over time, though Rutgers University notes that carpenter ant damage rarely compromises the structural integrity of a building. They are, however, one of the top five pest ant groups in the country and can cause real problems in utility poles and trees. Finding winged carpenter ants indoors, especially in winter or early spring, strongly suggests a colony is already living inside your walls or woodwork.
Other Red Winged Ants You Might See
Fire Ant Swarmers
If you live in the southern U.S., winged fire ants are a real possibility. Fire ant alates are smaller than carpenter ants, typically reddish-brown, and emerge from mounds when soil temperatures climb into the 70s Fahrenheit, usually from late spring into summer. Their mounds often appear first near sidewalks, driveways, or concrete slabs because those surfaces warm the soil faster. Fire ant stings are painful and can cause pustules, and a swarm near your home is worth addressing quickly.
Harvester Ants
Harvester ants are large, red, and found primarily in dry, open areas of the western and southern U.S. Their winged reproductives are impressive in size and easy to mistake for something more exotic. What really sets harvester ants apart is their sting. On the Schmidt Pain Index, a 1-to-4 scale of insect sting pain, harvester ants score a 3. The pain peaks around 20 to 30 minutes after the sting but can persist for over eight hours. One species, the Maricopa harvester ant, has the most toxic insect venom ever measured. Common side effects include redness, swelling, goosebumps, and a hard red welt that stays itchy for days. Allergic reactions are always a risk with any stinging insect.
The Red Velvet Ant (Not Actually an Ant)
If the insect you saw is fuzzy, bright red, and walking on the ground without wings, it’s likely a red velvet ant. Despite the name, these are solitary parasitic wasps. Females are wingless, which gives them their ant-like look. Males do have dark, translucent wings but are less commonly noticed. Females deliver an extremely painful sting, earning them the nickname “cow killer.” Males cannot sting. Red velvet ants don’t form colonies or build nests in your home, so they’re a curiosity rather than a pest problem.
Why Ants Grow Wings
Wings on ants aren’t permanent equipment for most of the colony. Only the reproductive members, queens and males, develop them, and only for one purpose: mating flights. At a certain point each year, a colony produces winged males (drones) and winged virgin queens (princesses). These alates wait for the right weather conditions, then launch into the air in large numbers.
This swarming event, called a nuptial flight, is timed so that alates from different colonies meet in the air. Scattering from multiple nests at once maximizes genetic diversity and reduces inbreeding. The timing depends on species and local weather. Most species need warm, humid, calm conditions with no rain or wind. For many species in temperate climates, this happens in July or August, though carpenter ants often swarm earlier in spring. After mating, males die within days. A newly mated queen lands, sheds her wings, and begins digging a nest to start a fresh colony. If you find discarded wings on a windowsill or near a doorway, a queen likely entered your home during or after her flight.
When Winged Ants Appear Indoors
Seeing a few winged ants outside during summer is completely normal and usually nothing to worry about. Seeing them inside your house is a different story, especially if it happens outside of the warm summer months. Finding winged carpenter ants indoors during late winter or early spring is a strong signal that a colony has established itself somewhere in the structure, because outdoor colonies wouldn’t be producing alates in cold weather.
Even during normal swarming season, a burst of winged ants inside your home means they’re either nesting nearby or finding easy entry points. Try to trace the ants back to where they’re coming from. Common entry points include gaps beneath exterior doors, window sills, and spots where pipes or wires pass through the wall.
How to Get Rid of Them
The approach depends on whether the colony is inside or outside your home. For ants nesting indoors, or when you can’t find the nest, bait stations are the most effective option for homeowners. Ant baits combine a food attractant with a slow-acting insecticide. Foraging workers carry the bait back to the nest and share it with the queen and the rest of the colony, which can eventually destroy the entire population. Place baits directly next to ant trails or wherever you see the most activity. For gel baits, put dabs on a piece of masking tape or wax paper to protect surfaces.
One important rule: don’t spray insecticides or cleaning products near your bait placements. Sprays will repel ants and keep them from eating the bait, which defeats the purpose. Similarly, avoid wiping away ant trails if you’re using bait, since those invisible scent paths are what guide workers to your bait and back to the nest.
For outdoor nests you can see, a liquid drench applied directly to the nest opening is often effective. Granular outdoor baits also work well for ground-nesting species like fire ants and harvester ants.
To prevent future invasions, seal gaps around doors, windows, and utility entry points. Trim back shrubs and tree branches that touch the building, since ants use these as bridges. Inside, reduce access to food and moisture by cleaning up spills promptly, storing pet food in sealed containers, and keeping trash covered. For carpenter ants specifically, fix any moisture problems in your home. They strongly prefer damp, softened wood for nesting, so leaky pipes, poor drainage, and wet crawl spaces are what attract them in the first place.