The short answer
- The swarmers themselves can't damage wood and live only about a day; sweep or vacuum them up.[1]
- Save a few (or their wings) so the termites can be identified and told apart from winged ants.[1][5]
- Then get inspections from more than one licensed company. Termites damage wood slowly, so you have time to compare.[1]
- Swarms from stumps or woodpiles out in the yard don't necessarily mean the house is infested; swarmers next to the foundation or indoors are a much stronger sign.[1][3]
- Spraying the swarmers kills only the ones you can see. NC State says it does nothing about the colony feeding in the wood, so the real fix is an inspection and, if termites are confirmed, a treatment.[9][11]
- If you already have a termite contract, call that company right away and have them check it, NC State advises.[9]
When and why termites swarm
Swarming is triggered by warmer temperatures and rainfall; the winged termites fly, drop to the ground, shed their wings, pair off and try to start new colonies in the soil.[1]
Native subterranean termites swarm during the day, most often in spring; in Mississippi's coastal counties swarms can start in late January, and in the northern counties they run April through June.[4][5]
Formosan subterranean termites swarm at night and are attracted to lights; in south Mississippi usually late April to mid-May, and in Texas early May through June.[4][5]
Drywood termites swarm in summer and fall in California, during the day for the western drywood termite.[6]
In buildings with heated basements, termites occasionally swarm indoors in winter.[3]
Texas A&M lists heat, day length and moisture as the triggers and says each species has its own set of conditions. In Texas, native subterranean swarms start in January in the south but not until April or May in the Panhandle. In North Carolina, NC State says at least three native species swarm from late winter into September or October.[7][9]
Sources differ on the time of day for native subterranean termites. Mississippi State says swarms usually happen in the morning, while Texas A&M and UC IPM say the afternoon. All agree they fly in daylight, often on a warm, sunny day after rain.[4][5][12][9]
A single swarm is short. The Texas Department of Agriculture says termites generally swarm once a year for about 24 hours. Mississippi State notes the Formosan swarm season lasts only a few weeks.[11][4]
Where you'll see them
Swarmers are attracted to light, so they gather around windows and doors; shed wings pile up on windowsills and along the edges of floors.[1][2]
Inside, swarmers come out and crawl or fly around in large numbers, and most head for the light. Afterward the only clue may be broken wings near windows and doors.[8]
Subterranean termites sometimes build mud tubes just for swarming, called swarm tubes, so the winged kings and queens can get out and fly away. A swarm is also one of the few times you can see live termites and possibly spot where they are coming out in the home, so note the place before you clean up.[12]
What the swarm tells you
Texas A&M says swarming termites inside a house usually mean an active infestation in that structure. Kentucky Extension adds that swarmers coming out next to the foundation or from an attached porch or patio mean there's a good chance the house is infested too.[7][1]
- Swarmers in the yard: UC IPM points out that most soil around a home holds buried roots, stumps or fence posts, so a swarm outdoors doesn't necessarily mean the house has termites. NC State calls it a reminder that termites live around us.[12][9]
- A swarm means a mature colony. A native subterranean colony takes 3 to 5 years to mature, and Texas A&M says a mature one usually has about 250,000 workers. The number of swarmers grows with the age and size of the colony.[7][9]
- No swarm doesn't mean no termites. Texas A&M says a new colony can also form without swarming when a group of termites is cut off from the main colony and sets up on its own, called budding.[7]
- Many homeowners only learn they have termites from a swarm. The EPA says most people don't know until they see one or find damage during construction.[10]
- A Formosan swarm points to a colony nearby. Texas A&M says it suggests the termites may be attacking a nearby building or tree.[5]
What to do the day of the swarm
There's time to do this properly. NC State's advice is not to panic and not to rush the decision, because termites don't do significant damage in a few days or weeks. The Texas Department of Agriculture says the same.[9][11]
- Collect some swarmers. The Texas Department of Agriculture suggests a plastic bag of them for the inspector. For a lab, Texas A&M says to put them in a vial of 70% alcohol so they don't dry out and the wings stay intact; Mississippi State says ethyl alcohol.[11][7][4]
- Pick up a few shed wings too. Texas A&M says the wings left at windows can be collected and used for identification.[5]
- Vacuum or sweep up the rest. A household flying-insect spray will also kill them, the Texas Department of Agriculture notes, but it doesn't touch the infestation.[1][11][9]
- If you have a termite contract, call the company and have them check the problem. If you don't, NC State suggests having two or three companies inspect and explain what they found before you choose.[9][1]
- Be wary of any firm that pushes you to sign right away with specials or scare tactics, Kentucky Extension says. Extra days spent comparing generally make no difference to the damage.[1]
- Don't plan to treat a home infestation yourself. Kentucky Extension says entry points are often hidden and the work takes masonry drills, large spray tanks and soil-injection rods, with hundreds of gallons of termiticide injected along the foundation, under slabs and inside foundation walls.[1]
Drywood and Formosan swarms
Which termite swarmed changes the plan, so identification matters more than usual.[5][4]
- Drywood termites live deep inside wood and are rarely seen until they swarm. UC IPM says sizing up a drywood infestation takes experience and is best left to a professional.[13]
- Drywood swarmers can start new infestations inside the same building. Mississippi State describes West Indian drywood termites spreading from one piece of imported furniture to other furniture and built-in cabinets until the building had to be tented and fumigated.[4]
- Formosan swarmers can start colonies above ground in wood kept moist by structural or plumbing leaks, or in places like rooftop planters and piles of rotting leaves, Mississippi State says.[4]
- Some Texas termite contracts exclude Formosan termites, so Texas A&M advises confirming the exact species before you sign.[5]
- For size, color and swarm times of each species, see the types of termites guide.[4][6]
Swarmers after a termite treatment
Liquid termiticides are supposed to control termites for at least five years when applied according to the label. Kentucky Extension says that if termites swarm and keep infesting the house the year after treatment, the cause is not the chemical breaking down but termites finding an untreated gap in the barrier.[1]
- That doesn't automatically mean the job was done badly. Even good treatments can fail where termites find a gap in the soil, and Kentucky Extension says companies will retreat at no extra charge if you bought and kept up the warranty.[1]
- Spot treatments are usually a gamble except for warranty retreatments, because a colony forages in many directions and termites will likely find another way in.[1]
- A house with a history of subterranean termites is especially open to reinfestation. UC IPM recommends a professional inspection every several years.[12]
What happens next
Most swarmers die during the flight; very few pair up and start a colony, and very few colonies ever reach maturity.[3]
A licensed inspector can find where termites are entering; the signs are often in crawl spaces, attics and behind walls where homeowners can't safely look.[3][1]
In cold areas termite feeding often slows in winter but doesn't necessarily stop. NC State says termites sheltered under a slab may stay active year-round, and UC IPM notes swarmers occasionally come indoors in winter in buildings with heated basements.[9][3]
Common questions
- Will the swarmers eat my house?
- No. Swarmers that emerge indoors can't damage wood and die in about a day; the colony that produced them is the concern.[1]
- Do I need treatment the same day?
- No. Termites damage wood slowly; take the time to get more than one inspection and estimate.[1]
- Are swarmers in the yard a problem?
- Not by themselves. Buried roots, stumps and old fence posts feed termites in most yards. Swarmers coming out against the foundation or from an attached porch or patio are the ones that point to the house.[12][1]
- Should I spray the swarmers?
- You can, but it only kills the swarmers you see. Vacuuming works as well, and neither stops the colony in the wood.[11][9][1]
- How long does a termite swarm last?
- The Texas Department of Agriculture says termites generally swarm once a year for about 24 hours. Indoor swarmers live only about a day.[11][1]
- I had termites treated and they swarmed again. What now?
- Call the company that did the work. Kentucky Extension says a swarm the following year usually means an untreated gap, and companies retreat at no charge when the warranty has been kept up.[1]
After the swarm
Sources
- University of Kentucky Entomology, “ENTFACT-604: Termite Control: Answers for Homeowners (revised March 2026).” entomology.mgcafe.uky.edu/ef604 (accessed 2026-10-06)
- University of Kentucky Entomology, “ENTFACT-605: Protecting your Home Against Termites (revised March 2026).” entomology.mgcafe.uky.edu/ef605 (accessed 2026-10-06)
- University of California Statewide IPM Program, “Pest Notes: Subterranean and Other Termites, Publication 7415 (May 2014).” ipm.ucanr.edu/legacy_assets/PDF/PESTNOTES/pntermites.pdf (accessed 2026-10-06)
- Mississippi State University Extension, “Species of Termites in Mississippi.” extension.msstate.edu/insects/termites/species-termites-mississippi (accessed 2026-10-06)
- Texas A&M AgriLife Extension, “Formosan Subterranean Termites, E-367.” extensionentomology.tamu.edu/wp-content/uploads/sites/3/2017/01/Formosan-subterranean-termites-E367.pdf (accessed 2026-10-06)
- University of California Statewide IPM Program, “Pest Notes: Drywood Termites, Publication 7440 (August 2014).” ipm.ucanr.edu/legacy_assets/PDF/PESTNOTES/pndrywoodtermites.pdf (accessed 2026-10-06)
- Texas A&M AgriLife Extension, “Subterranean Termites, E-368 (R.E. Gold, K.M. Schofield, E. Brown and M. Keck, 9/10).” extensionentomology.tamu.edu/wp-content/uploads/sites/3/2017/01/Subterranean-termites-E368.pdf (accessed 2026-11-10)
- Kansas State University Agricultural Experiment Station and Cooperative Extension Service, “Termites, MF-722.” bookstore.ksre.ksu.edu/pubs/MF722.pdf (accessed 2026-11-10)
- NC State Extension, “Termites: Biology and Control.” content.ces.ncsu.edu/termites-biology-and-control (accessed 2026-11-10)
- U.S. Environmental Protection Agency, “Termites: How to Identify and Control Them.” www.epa.gov/safepestcontrol/termites-how-identify-and-control-them (accessed 2026-11-10)
- Texas Department of Agriculture, “Termite FAQs (Structural Pest Control Service).” texasagriculture.gov/Regulatory-Programs/Pesticides/Structural-Pest-Control-Service/Termite-Fumigation-Applications/Termite-FAQs (accessed 2026-11-10)
- University of California Statewide IPM Program, “Pest Notes: Subterranean and Other Termites, Publication 7415 (web edition).” ipm.ucanr.edu/home-and-landscape/subterranean-and-other-termites/ (accessed 2026-11-10)
- University of California Statewide IPM Program, “Pest Notes: Drywood Termites (web edition).” ipm.ucanr.edu/home-and-landscape/drywood-termites/ (accessed 2026-11-10)