Females: about 1 year, up to 2 (ADW). Males: under a year. Egg to adult: about 7 weeks (Ohio State). Season: emerge and mate April–early May; new adults out in late August; hibernate in old galleries. Stings: males can't; females rarely.
How long do carpenter bees live?
How long do carpenter bees live? Female eastern carpenter bees (Xylocopa virginica) live about a year on average and up to two years (Animal Diversity Web). Males live less than a year: newly emerged males overwinter with the females in the nest "but die in the following spring" (Animal Diversity Web), and Ohio State notes that "males likewise are short lived."
That makes the carpenter bee lifespan one of the longest of any bee you're likely to see around a house. Most of a carpenter bee's adult life is spent quietly inside a tunnel in wood: the new adults that appear in late summer feed for a while, then hibernate in the gallery where they grew up and emerge the next spring to mate and nest (Ohio State).
The tool above tells you what carpenter bees are doing in the month you choose, how long they live, and — if you've seen fresh holes — how to protect your wood without harming them.
| Lifespan | Source | |
|---|---|---|
| Female | 1–2 years (about a year on average, up to two years) | Animal Diversity Web |
| Male | under a year: overwinters, then dies in late spring | Animal Diversity Web; Ohio State |
| Egg to adult | about seven weeks, depending on temperature | Ohio State |
Carpenter bee life cycle
The carpenter bee life cycle takes a year, with one generation in the northern United States and sometimes two in the south (Ohio State):
- Spring emergence and mating (April–early May). "Male and female carpenter bees emerge in the spring (April and early May) and mate. Territorial males hover nearby as mated females begin nesting activities" (Ohio State).
- Nesting. A female prefers to clean out an old gallery rather than dig a new one, because tunnelling is slow: about an inch every six days. A new gallery starts as a round entrance hole slightly less than half an inch wide, bored across the grain, then turns about 90 degrees and runs 4–6 inches along the grain. Galleries reused for years can reach 10 feet (Ohio State).
- Eggs. At the far end she packs a ball of pollen and nectar, lays an egg on it and seals the cell with chewed wood pulp — six to ten cells in a row, after which "she dies soon thereafter" (Ohio State). The University of Kentucky describes "about five or six cells".
- Larvae and pupae. Each larva eats its food ball, pupates and becomes an adult in about seven weeks (Ohio State).
- New adults. They stay in the gallery for several weeks, then "chew through the cell partitions and venture outside in late August to feed" (Ohio State). They collect and store pollen in the gallery and spend much of their time huddled together inside.
- Winter. The new adults "hibernate within their old nest gallery and then emerge the following spring" (Ohio State). The University of Kentucky notes they overwinter individually, often in previously built tunnels.
| Month | Northern Hemisphere | Southern Hemisphere |
|---|---|---|
| January | Adults hibernating in old galleries | Young developing in the wood |
| February | Adults hibernating in old galleries | New adults out feeding |
| March | Adults hibernating in old galleries | New adults out feeding |
| April | Emerging, mating and nesting | Adults hibernating in old galleries |
| May | Emerging, mating and nesting | Adults hibernating in old galleries |
| June | Young developing in the wood | Adults hibernating in old galleries |
| July | Young developing in the wood | Adults hibernating in old galleries |
| August | New adults out feeding | Adults hibernating in old galleries |
| September | New adults out feeding | Adults hibernating in old galleries |
| October | Adults hibernating in old galleries | Emerging, mating and nesting |
| November | Adults hibernating in old galleries | Emerging, mating and nesting |
| December | Adults hibernating in old galleries | Young developing in the wood |
Calendar from Ohio State (emergence, development, late-August flights, overwintering) and Animal Diversity Web. Southern Hemisphere months are our six-month shift; carpenter bee species differ around the world.
Carpenter bee season
The carpenter bee season you notice is spring: big bees hovering at eaves, decks and fascia boards in April and May, males chasing anything that moves. A second, quieter burst of activity comes in late summer when the new adults feed. From autumn to early spring they're out of sight, hibernating in the wood.
Inside the gallery
A carpenter bee spends most of its long life indoors, in wood. The new adults that chew out of their cells in late summer "collect and store pollen in the existing galleries but also spend much of their time just huddled together inside the same gallery where they developed" (Ohio State). The gallery then shelters them through the winter: "Carpenter bee galleries are a critical resource, since the bees spend much of their time inside a gallery and they require its protective conditions to survive the winter" (Ohio State). That's why females would rather refurbish an old gallery than dig a new one, and why damage grows slowly over years in the same boards.
Male carpenter bees
The bees that buzz around your head at a deck or porch in spring are usually males guarding the area where females are nesting. "Territorial males hover nearby as mated females begin nesting activities," and although they "dive-bomb" people, "these bees are bluffing as they lack a stinger and are harmless" (Ohio State). They live less than a year — emerging in late summer, spending the winter in the gallery and dying in late spring after the mating season (Animal Diversity Web).
Carpenter bee vs bumble bee
Large carpenter bees are easy to mistake for bumble bees. The quickest check is the abdomen:
| Carpenter bee | Bumble bee | |
|---|---|---|
| Abdomen | largely bare and shiny black on top (Ohio State) | very hairy, usually with yellow bands (Ohio State; University of Kentucky) |
| Nest | tunnels it bores in wood | existing cavities: grass, old rodent holes, compost (University of Kentucky; BBCT) |
| Social life | solitary or small groups | annual colonies of 30 to 400+ |
| Female lifespan | 1–2 years | queen up to 1 year; workers 28–42 days |
For bumble bee lifespans by caste, see the bumble bee lifespan calculator.
Do carpenter bees sting?
Rarely. "Male carpenter bees often cause alarm when they dive-bomb ... but in actuality, these bees are bluffing as they lack a stinger and are harmless." Females "are docile and are reported to sting only if handled," though a female can sting more than once (Ohio State). The University of Kentucky agrees that females "will seldom do so — unless they are handled or bothered by people."
When do carpenter bees go away?
The hovering and chasing dies down by early summer, once mating is over and females are busy inside their galleries; the University of Kentucky notes that nest-searching "usually subsides by late spring." The old adults die off over the summer, the new generation appears briefly in late August, and from autumn they're hidden inside the wood until the next April (Ohio State; Animal Diversity Web).
They don't really go away, though — they go inside. A gallery is "a critical resource", and bees spend much of their lives in one (Ohio State), so the same boards tend to be used year after year unless the wood is protected.
Carpenter bee holes in wood
Carpenter bee holes are perfectly round, "about the diameter of your little finger" (University of Kentucky) — just under half an inch (Ohio State) — bored across the grain before the tunnel turns to run along it. Eastern carpenter bees prefer softwoods such as cedar, redwood, cypress, pine and fir, and weathered, unpainted wood (Ohio State; University of Kentucky). One hole means one gallery, but many bees can use connected galleries over the years.
Protecting wood without harming bees
Carpenter bees are pollinators, and you can protect wood without killing them. These are the non-chemical measures in the extension guides:
- Paint, don't stain. "Keep all exposed wood surfaces well painted with a polyurethane or oil-based paint to deter attack by carpenter bees ... Wood stains will not prevent damage" (Ohio State). "Carpenter bees usually will not tunnel into painted wood" (University of Kentucky).
- Keep the paint in good repair. Weathering exposes bare wood the bees can attack, so inspect painted surfaces regularly (Ohio State).
- Use other materials. Carpenter bees "do not damage non-wood materials including aluminum, asbestos, asphalt, and vinyl siding" (Ohio State).
- Close up in spring. Keep garages and outbuildings closed while bees are searching for nest sites (University of Kentucky).
- Fill old holes after the season. Plug holes with a wooden dowel and wood glue or wood putty; Penn State Extension suggests doing it in the fall. Bees sealed inside a gallery "typically will not chew out" (Ohio State), so only plug holes you're sure are empty — after the new adults have left in late summer, or once you've seen no activity for some time — then paint over the repair.
Some guides also describe insecticides and traps that kill bees; we don't recommend them. If carpenter bees are damaging a structure badly, a professional can advise on repairs.
How this tool works
- Stage: the month you choose is matched to the calendar above (Ohio State; Animal Diversity Web). Southern Hemisphere months are shifted by six — our assumption, as the research is from the eastern United States.
- Lifespan: females about a year, up to two; males under a year (Animal Diversity Web) — the same figures used by the bee lifespan calculator.
- Holes this year: changes the advice order — during nesting, don't seal holes that may hold bees; after the season, fill empty holes and paint.
Frequently asked questions
How long do carpenter bees live?
Females about a year on average and up to two; males less than a year — they overwinter and die the next spring (Animal Diversity Web).
What is the carpenter bee lifespan from egg to adult?
About seven weeks from egg to adult, depending on temperature (Ohio State).
What is the carpenter bee life cycle?
Spring emergence and mating, nesting and egg laying in wood galleries, seven weeks of development, new adults out in late August, then hibernation in the gallery (Ohio State).
When is carpenter bee season?
April and early May for emergence and mating; a second, smaller burst of activity in late August (Ohio State).
When do carpenter bees go away?
Nest-searching usually subsides by late spring (University of Kentucky); from autumn to spring they hibernate inside the wood (Ohio State).
Do carpenter bees sting?
Males can't. Females rarely sting, and only if handled (Ohio State; University of Kentucky).
How do I tell a carpenter bee from a bumble bee?
A carpenter bee's abdomen is largely bare and shiny black; a bumble bee's is hairy, usually with yellow bands (Ohio State).
How big are carpenter bee holes?
Perfectly round and just under half an inch across — about the width of a little finger (Ohio State; University of Kentucky).
How can I stop carpenter bees without killing them?
Paint exposed wood with polyurethane or oil-based paint, keep it maintained, use non-wood materials, close outbuildings in spring and plug empty holes after the season (Ohio State; University of Kentucky; Penn State).
How many generations of carpenter bees are there a year?
One in the northern United States, sometimes two in the south (Ohio State).
Do carpenter bees reuse holes?
Yes. Females prefer to refurbish an old gallery, and a gallery used for years can reach 10 feet (Ohio State).
These calculators give estimates from research and extension figures, for education. Bees are important pollinators — never spray a swarm or a colony. For a swarm or bees in a wall, contact a local beekeeper, a bee-removal specialist or your Extension office (Mississippi State; UGA Extension). If a sting causes trouble breathing, swelling of the face or throat or faintness, call emergency services (UC IPM).