It’s a warm afternoon in early May. You walk down into the basement and see a swarm of winged bugs near the sliding glass door. Dozens of them. A pile of tiny translucent wings has collected on the sill. You’re not even sure if they’re ants or something else, but you know enough to be worried.
Here’s the straight answer: a spring swarm of winged insects inside your home in the Midwest is almost always subterranean termites. And a termite swarm inside your house isn’t a fluke. It’s the visible signal of a colony that’s been quietly growing inside or under the structure for years.
That sounds scary. It shouldn’t feel like a crisis. It should feel like a call you make this week, not next month. Below is how to identify what you’re looking at in about thirty seconds, what a swarm actually tells you, and what to do right now.
Termite Swarmer or Flying Ant? How to Tell in 30 Seconds
Most homeowners who find winged bugs indoors assume it’s flying ants, because flying ants are more familiar. Sometimes it is. Often it isn’t. Here are the three tests that settle it.
Wings. Termite swarmers have four wings that are all roughly the same length. Flying ants have four wings too, but the front pair is noticeably larger than the back pair. If all four wings look the same size, you’re looking at a termite.
Waist. Termite swarmers have a thick, straight waist. The body looks like one continuous tube with no real narrowing. Flying ants have a clear pinched “wasp waist” between the thorax and the abdomen. Straight body equals termite. Pinched middle equals ant.
Antennae. Termite antennae are straight and look like tiny strings of beads. Flying ant antennae are elbowed, meaning there’s a clear bend partway down the antenna, like a little arm joint. Straight antennae equal termite. Bent antennae equal ant.
One more practical note: swarmers drop their wings fairly quickly after swarming. Plenty of homeowners never actually see the insects themselves. What they find is a pile of tiny, translucent, equal-sized wings on a windowsill, near a light fixture, on a basement floor, or around a basement window. Piles of matching translucent wings are a termite tell.
If you can, scoop two or three specimens (wings or bodies) into a sealed bag or small container. A pest professional can confirm the species quickly from a clear sample.
What a Swarm Indoors Actually Means
This is the part most homeowners don’t know, and it’s the part that matters.
Termite colonies don’t produce swarmers right away. A subterranean termite colony typically takes several years to mature to the point where it sends out reproductive swarmers, commonly cited as three to five years or more. The swarmers are the colony’s way of expanding: winged reproductives leave the nest, pair off, shed their wings, and try to start new colonies somewhere nearby.
That timeline is why a swarm inside your house is significant. It isn’t a colony that wandered in through a cracked door. Subterranean termite swarmers inside a structure almost always indicate an established colony inside or immediately beneath that structure. The colony has been there, quietly eating cellulose, for years before you saw the first winged bug on the sill.
The good news is that you noticed. A lot of homeowners don’t notice until there’s visible wood damage. Acting this week is materially better than acting next month. Subterranean termites feed on cellulose, which means wood, paper, and cardboard. They don’t touch concrete or pressure-treated materials, but they’re happy to travel past those to get to framing and trim that are accessible.
You haven’t just discovered a termite problem. You’ve discovered the visible stage of a problem that’s been going on behind the scenes.
Other Signs Worth Checking For
Once you’ve identified swarmers, spend a few minutes checking for the other common signs. If you find any of these on top of a swarm, you have strong evidence of an active colony.
Mud tubes. Subterranean termites travel between the soil and wood through pencil-width tunnels made of dirt and saliva. Look along the foundation inside and outside the house, on basement walls, on crawl-space joists, and on any wood near ground contact. The tubes are usually the diameter of a pencil, brown or gray, and obviously earthen.
Hollow or crumbly wood. Tap baseboards, door frames, window frames, and any wood near soil or moisture in the lower levels of the house. Termite-damaged wood often sounds hollow or feels papery when pressed. Focus on the lowest floors first.
Blistered or warped paint. Termite galleries just below the surface of painted wood trim can cause the paint to bubble, ripple, or warp. It can look like water damage at first glance.
Sawdust piles. Small piles of what looks like sawdust are more commonly a carpenter ant sign, not termites (termites don’t push wood out of their galleries the way carpenter ants do). Worth noting so you can tell the difference. You can read our carpenter ants pest library page for more on that pest.
What to Do Right Now
A few practical things help. A few things hurt.
Don’t spray store-bought insecticide at the swarm. It feels like the right move. It isn’t. You’ll kill the swarmers you can see and leave the colony completely untouched. You’re treating the symptom, not the problem, and you’re making the next step harder for a professional.
Save a few specimens. Vacuum the rest up or wipe them with a paper towel if you need to, but put two or three in a sealed bag or small container. A clear sample makes species identification fast.
Note where you saw them. Which window, which room, which side of the house. That location is close to a colony access point and helps guide a professional inspection.
Reduce conditions termites love while you wait. Pull mulch back from the foundation so there’s a gap between mulch and siding. Move firewood stacks at least twenty feet from the house. Address any known moisture leaks, because subterranean termites need moisture to survive. These steps don’t fix an active colony, but they don’t hurt, and they help prevent future ones.
The boundary is clear: termite identification and treatment is a professional job. Over-the-counter products don’t reach the colony, and the wrong treatment can drive the colony deeper into the structure. PCC offers termite treatment as part of our residential services. An inspection confirms what you’re dealing with and sets up a treatment plan tailored to your home.
What to Do If You See Swarmers
A swarm of winged bugs inside your home in May, in Illinois, Iowa, Wisconsin, or Michigan, is almost never flying ants. It’s almost always subterranean termites, and it points to a colony that’s been growing quietly inside or under the structure for years.
The good news is this is a well-understood pest with real treatment options. The better news is you caught it. A lot of homeowners don’t notice until damage is already done.
PCC has served homeowners across IL, IA, WI, and MI for more than twenty years. Termite treatment is part of what we do. If you’ve found winged bugs or a pile of translucent wings in your home, don’t wait.
Schedule your service and let’s get this looked at.