Yes, some termites swarm at night. Formosan subterranean termites are the most common nighttime swarmers, taking flight after dark in late May and early June and flying directly toward any light source they can find. Other species, like eastern subterranean termites, tend to swarm during the day, while drywood termites can swarm at various times depending on the species. If you’ve spotted winged insects around your porch lights or indoor lamps after sunset, there’s a good chance you’re looking at termite swarmers.
Which Termites Swarm at Night
Formosan subterranean termites are the primary nighttime swarmers in the United States. These yellowish-brown insects measure about half an inch long and are sometimes called “super termites” because their colonies can contain millions of individuals. According to Texas A&M University’s Urban Entomology Program, Formosan termites swarm at night in late May and early June, and they are strongly attracted to lights.
Eastern subterranean termites, the most common species across much of the country, typically swarm during daylight hours, often on warm days following a rain. Drywood termites vary more widely. Some drywood species swarm in the evening or at dusk, while others prefer daytime. If you’re seeing swarmers well after dark, Formosan termites are the most likely culprit, especially in the Gulf Coast states, Hawaii, and other warm, humid regions where they’ve become established.
Why Light Draws Them to Your Home
Nighttime swarmers don’t target your house because they want to eat it. The winged termites leaving a colony are reproductives, called alates, and their only goal is to find a mate and start a new colony. They’re powerfully drawn to light, which is why porch lights, security lights, and bright indoor lamps essentially act as beacons. Formosan swarmers will fly toward lit windows, squeeze through vents, and crawl under doors to reach the light source.
Once they land, they shed their wings and search for a partner. A mated pair then looks for moist soil or wood to begin building a new colony. The swarmers themselves aren’t eating your home that night, but a pair that successfully settles into damp wood or soil near your foundation can eventually produce a colony that does serious structural damage.
Replacing bright white outdoor bulbs with yellow or amber bulbs significantly reduces the number of swarming termites (and other flying insects) drawn to your home. Turning off unnecessary exterior and interior lights during peak swarm season is one of the simplest things you can do to avoid attracting them.
Signs a Swarm Happened While You Slept
Because Formosan termites swarm at night, you might miss the event entirely and only find the evidence the next morning. The most telltale sign is piles of small, pale, translucent wings near windowsills, light fixtures, or on the floor beneath lamps. Swarmers shed their wings quickly after landing, so even a brief swarm can leave behind dozens or hundreds of discarded wings.
You may also find dead swarmers on windowsills or clustered near light sources. Live swarmers crawling indoors, especially emerging from walls, ceilings, or floors, are a more serious indicator. A few swarmers that wandered in from an outdoor colony through a gap under the door are less alarming than swarmers pushing out from inside the structure itself. The second scenario strongly suggests an active colony is already living in your home.
Termite Swarmers vs. Flying Ants
Flying ants swarm around the same time of year and look similar at first glance, so it’s worth knowing the differences before you panic. Three quick features separate them:
- Waist shape: Termites have a straight, thick body from head to tail. Flying ants have a pinched “wasp waist” between the thorax and abdomen.
- Wings: Termite swarmers have four wings that are all the same size and shape, pale and translucent. Flying ants have front wings noticeably longer than the back pair, often tinted brown.
- Antennae: Termite antennae are straight. Ant antennae bend at an angle, like an elbow.
If you’re unsure, collect a few of the insects (or their wings) in a plastic bag. Any pest control professional can identify them quickly.
What to Do During a Nighttime Swarm
If swarmers are actively flying around your home at night, turn off as many lights as you can, both inside and outside. This won’t stop a swarm already in progress from a colony inside your walls, but it will reduce the number of outside swarmers drawn to your home. Close windows, seal gaps under doors if possible, and shut off porch and patio lights.
Swarmers that make it inside aren’t a structural threat on their own. They’re fragile, short-lived, and most will die within hours without finding suitable moist soil or wood. You can vacuum them up. The real concern is what the swarm tells you: if termites are emerging from inside the building, from cracks in walls, from around window frames, or from the floor, that means an established colony is already present and has been feeding on wood in the structure long enough to produce reproductive swarmers. That typically takes a colony several years.
Swarmers coming from outside and accidentally entering through open windows or doors are less immediately concerning but still worth noting. Formosan colonies in nearby trees or soil can eventually spread to a home’s foundation. Either way, a professional inspection after a swarm is a smart next step, particularly if you found wings or dead swarmers inside the house. A trained inspector can determine whether the swarmers originated from within the structure or wandered in from outside, and that distinction changes everything about how urgent the situation is.