Bat exclusion
Bat exclusion is the standard, legal way to get a colony out of a building. Every gap the bats could use is sealed except the ones they fly out of each night, and those get one-way devices: a tube, cone or mesh flap that lets a bat crawl out but not back in. After a week or so of clear evenings the house is empty, the devices come down and the last gaps are sealed for good.
For a colony under 50 bats the work usually runs $400 to $1,500; larger colonies with several exits cost $2,000 to $8,000 or more. Nothing is trapped, poisoned or killed, which matters because bats are protected and several species are now endangered.
When exclusion is the answer
- You see bats leaving the roofline, a gable vent or a chimney at dusk.
- There are droppings on a porch, windowsill or attic floor, piled below one spot.
- You hear scratching or squeaking in the attic or walls in the evening.
- A bat has turned up inside the house more than once.
- You have bats in a barn, church or outbuilding that people use.
- You are selling the house and the inspector noted bat activity.
What bat exclusion costs
| Job | Typical price |
|---|---|
| Inspection Finding the roost and every gap; often credited against the job | $75 to $400 |
| Under 50 bats Exclusion devices and sealing | $400 to $1,500 |
| 50 to 200 bats Several exits, more sealing | $2,000 to $8,000 |
| Over 200 bats Large colony, often several roosts | $5,000 to $8,500+ |
| Sealing entry points Where billed separately from the exclusion | $150 to $1,500 |
Ranges drawn from three national home-services cost guides, checked November 2026. US dollars. A guide, not a quote. More detail in the bat removal cost guide.
Timing: when exclusion is allowed
Bats form maternity colonies in late spring. Pups are born around late May or June and cannot fly until about mid-July, so excluding the mothers then would leave the young to starve in your attic. Most states with rules put the no-exclusion window somewhere between April and mid-August, while flightless pups are in the roost: Florida bans exclusion from April 15 to August 15 (FWC), New Jersey from May 1 to July 31 (NJ Fish and Wildlife), and Wisconsin from June 1 to August 15 (Wisconsin DNR).
In practice that leaves two good windows in most of the country: early spring, before the colony settles, and late summer into early fall, once the young can fly. In colder states, bats that stay through winter hibernate, and exclusion in winter is also restricted or needs proof the bats have gone. If a bat gets into living space during the closed season, interior gaps can be sealed at any time; it is the outside exits that must wait. Full table on our home page.
What decides how the job goes
Finding every gap
Bats squeeze through openings about the width of a dime, and CDC advises caulking anything bigger than that. A thorough inspection covers ridge vents, soffit returns, fascia, chimney flashing, siding joints and pipe penetrations, often from a ladder or lift.
Where the devices go
Devices go only on the active exits, found by watching the house at dusk. Fit them on the wrong gap and the bats simply use another one.
Weather and nights
Bats stay in when it is cold, windy or wet. Florida requires devices up for at least four nights with lows of 50°F or warmer; Ohio asks for at least a week.
Sealing materials
Durable sealant, mesh, flashing and trim that suits the house. Expanding foam on its own tends to fail within a season.
Height and access
Steep roofs, three-story gables and tile roofs mean harnesses or a lift, and that is usually the biggest single driver of price.
A written warranty
Ask what happens if bats get back in. Many firms re-check and reseal for a year or more on the work they did.
Want the bats out before the next maternity season?
Get a quoteHow an exclusion runs
Inspection and dusk watch
The house is checked for gaps and droppings, and someone watches at dusk to see exactly where bats leave.
Seal the rest
Every gap that is not an active exit is sealed, so the bats are left with only the exits that get devices.
One-way devices
Tubes, cones or mesh go over the active exits. Bats leave to feed and cannot get back in.
Final seal
Once the roost is confirmed empty, the devices come off and those last exits are sealed for good.
What exclusion is not
Trapping, poisoning, glue boards and foggers are illegal on bats in several states and do not work: a poisoned bat is more likely to end up on the floor of a bedroom. Ultrasonic repellers and mothballs have no reliable effect. And sealing the house while bats are inside traps them, which Ohio's rules name outright as prohibited. The Ohio Division of Wildlife guidelines are a clear, short read on what is and is not allowed.
Before you book
How long does bat exclusion take?
The visible work is often a day or two. The devices then stay up for at least four nights and usually a week or more, depending on the weather, before the final seal.
Is it legal to remove bats from my house?
Yes, by exclusion, outside your state's restricted season. Killing, trapping or sealing bats in is not allowed in many states, and some species are federally endangered.
Can I do bat exclusion myself?
It is legal in most states for an owner, but the hard part is finding every gap at height. Missed gaps are why DIY jobs fail. Never handle a bat, and see the CDC guidance first.
Will the bats come back?
Bats return to the same roost each year, so they will try. If every gap was sealed properly, they cannot get in and will move on. Many firms warranty their seal.
What happens to the bats?
They leave on their own to feed and roost somewhere else nearby. Some owners put up a bat house first so the colony has an alternative.
Should I clean up the guano at the same time?
Cleanup happens after the bats are out. Light droppings can be vacuumed with a HEPA unit; heavy buildup is a job for a crew in respirators. See bat guano cleanup.
Get a quote for bat exclusion
Start with your ZIP code. Contact details come next, then a few taps about the bats.
We are an introduction service, not a bat removal specialist. We pick one who works near you, tell you their name, and share your request only once you agree.
Got it. Your request is with us.
- Before close of business tomorrow you will hear from us with the name of a bat specialist working near you.
- Say yes and your request goes to that firm; say no and it goes nowhere.
- They arrange an inspection and give you a price. Your email is used for this request only, never for newsletters.
If a bat was in a room where someone was asleep, keep it contained if it is safe to do so and call your local health department today.