The short version
Trap the ones inside, then seal the gaps. An inspection usually costs $75–$250.
- Look for droppings, gnaw marks and night-time scratching.
- Across Greenwich, mice usually start moving indoors in September and October, as nights get colder.
- Traps remove them; sealing keeps them out.
- Never sweep or vacuum droppings dry.
Homeowners, renters and landlords in Greenwich who are hearing, seeing or smelling signs of rodents.
What to look for
A mouse fits through a gap the size of a dime. Seeing one in daylight usually means there are more. Rodents are mostly unseen. You hear them at night and find droppings by morning.
- 1Live sighting, especially during the day.
- 2Bait or pet food vanishing from bowls overnight.
- 3Fresh gnaw marks on door corners or garage weatherstripping.
- 4Burrow holes along the foundation, deck, or shed.
- 5Rodent hair or droppings inside HVAC ducts.
- 6Chewed holes in the bottom of cabinets or drawers.
Why it’s worth acting soon
- Mice breed fast, every few weeks.
- Droppings and urine contaminate food and insulation.
- Gnawed wiring can be a fire risk.
- Nests and odor get harder to clean the longer they stay.
Treatment options and typical costs
Inspection and Entry-Point Mapping
$75–$250
Many credit the fee if you go ahead. Ask. Ask whether the report lists every entry point, because in Greenwich that list is the real product.
- Time
- 60–90 minutes
- Best for
- Every job; nothing else works without it
Tamper-Resistant Exterior Bait Stations
$100–$300 setup, $40–$80 per service visit
Stations should be numbered and logged to show activity trends. A good pro shows you which stations get hit. Placement changes over time.
- Time
- 30–45 minutes per visit, ongoing
- Best for
- Outdoor rat pressure; ongoing perimeter protection
Snap-Trap Program
$150–$400 per visit
Placement matters more than bait. Rodents run along edges, so traps in Greenwich attics and kitchens go perpendicular to walls, in the dark corners where droppings cluster.
- Time
- 30–60 minutes per visit, 2–4 visits
- Best for
- Active indoor infestations; fast results you can see
Attic and Crawlspace Cleanup and Sanitation
$500–$3,000, higher if insulation is replaced
Not every Greenwich infestation needs a full cleanup; a few droppings can be cleaned with gloves and disinfectant. Heavy contamination across an attic is a different job entirely.
- Time
- Half day to two days
- Best for
- Heavy contamination; odor, urine-soaked insulation, nesting
Prices are typical published ranges. Ask what’s included before you compare quotes.
Roof rats and mice love attic insulation. Tunnels through the fluff, flattened runways and droppings along the eaves are the signs to look for.Which rodents live around Greenwich.
They're small, curious and breed quickly. Norway rats are the other usual suspect. They burrow along foundations and enter low. House mice are the most common rodent in Greenwich homes.
When they move in.
Spring is breeding season. Small problems grow fast. Check for gaps before then.
A metal vent cover with a working flap keeps mice out all winter. Plastic flaps crack in the cold and get chewed open.How they get into houses here.
Rodents use gaps around utility lines, dryer vents and window wells. Check where pipes and cables enter. Look at the dryer vent flap. Window wells need covers or screens. Homes from Greenwich out to Stamford and Norwalk share the same weak spots, so the checklist below works across the area. Plenty of homes in Greenwich have basements.
A year of rodents in Greenwich.
- Summer: with highs around 83°F in Greenwich, rodents look for water. Fix drips and leaks. - Fall: mice move indoors as nights cool. Seal gaps in September. - Winter: with lows near 23°F in Greenwich, check the attic, garage and pantry for droppings. - Spring: breeding season. Act on any sign quickly.
Mice or rats?
- Rub marks: rats leave greasy smudges along walls and beams. - Droppings: mouse droppings are rice-sized. Rat droppings are two or three times bigger. - Holes: mice chew dime-sized holes. Rats chew holes closer to quarter-sized. - Sounds: mice sound light and quick. Rats sound heavier. - Behavior: mice are curious about new traps. Rats avoid them for days.
Sealing small gaps yourself.
- Check your work: daylight through a gap means it isn’t sealed. - Steel wool or copper mesh: pack it into small gaps first. - Sealant or mortar: cover the mesh so it stays put. - Hardware cloth: use quarter-inch mesh over vents and larger holes. - Door sweeps: close the gap under garage and exterior doors. - Expanding foam: fine on top of mesh, useless on its own.
Cleaning up droppings safely.
- Wash your gloved hands, then your hands. - Air the room out for 30 minutes first. - Wear rubber or plastic gloves. - Spray droppings with a bleach solution, then wait five minutes. - Wipe up with paper towels and bag them. - Don’t sweep or vacuum droppings dry. It stirs up dust.
What happens at an inspection.
The inspector walks the outside first. They check the foundation, vents, rooflines and utility gaps. Inside, they check the kitchen, garage and attic. You should come away with a list of entry points. Photos help. Most inspections take about an hour.
Rodents in the car.
Park in a closed garage when you can. Check the air filter box for nesting. Clear birdseed and pet food from the garage. Mice and rats nest in engine bays and chew wiring.
Bird feeders and rodents.
Use a seed tray and sweep up spills. If rodents show up, bring feeders in at night. Store seed in a metal can with a tight lid. Spilled seed feeds mice and rats.
Questions to ask before you sign.
- Will you use poison inside? (Ask them not to.) - Where are they getting in? - Which gaps will you seal, and with what? - How many trap visits are included? - What happens if they come back? - Is cleanup included, or extra?
Rodents by the numbers.
Across Greenwich, what actually matters is a walk-through: where the droppings are, how the rodents are getting in, and how large the colony is. Across Greenwich, those three findings — species, entry points, and scale — are what a quote should be built on, not a regional average. Across Greenwich, ask any provider to show you the entry points and the plan before you compare numbers. National surveys set rough expectations but cannot diagnose one house.
What affects the price
- Follow-up visits included versus billed separately.
- Crawlspace or slab; crawlspaces add labor.
- Attic access and how much insulation is contaminated.
- Number of entry points found during inspection.
- Home size, stories, and roofline complexity.
- Outdoor pressure from creeks, alleys, or restaurants nearby.
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What's your biggest concern about rodents?
When to call for help
Call if you hear them in the attic or walls. Droppings in several rooms are another sign. So is a dead-rodent smell. Call right away if you see rats. They take a longer, more careful approach. Attic cleanup is hard to do safely without training.
What you can do yourself
That's where a pro's sealing work pays off. Rooflines, vents and attics are harder. Seal small gaps with steel wool and sealant. Store food in sealed bins. Bait them with peanut butter. Start tonight with snap traps along the walls.
Rodents in Greenwich
Greenwich gets about 51 inches of rain a year, and heavy storms flood burrows, which pushes rats toward buildings. Winter lows average around 23°F in Greenwich, and that cold is what sends mice looking for a way in. In Greenwich's neighborhoods, woodpiles, fences, bird feeders and gardens draw rodents close to the house. A typical home in Greenwich is worth around $1,500k, and chewed wiring or soiled insulation can get expensive. Across Greenwich, the humid continental climate means rodents activity tends to follow fall and winter (rodents move indoors for warmth), so scheduling the visit before the busy stretch usually means a faster response and a cleaner quote.
Local research
Rodents in Greenwich, CT: what the public record shows
Before you compare quotes, it helps to know which rodents actually live in Connecticut, when they are busiest around Greenwich, and what the state figures look like. Everything below links to the agency or university page it came from.
Rodent species recorded in Connecticut
- House mouse (Mus musculus) — Enters at 1/4 inch; 5-10 litters per year; eats about 200 small meals a night.
- Norway rat (Rattus norvegicus) — Burrowing rat of basements, sewers and ground floors; tail shorter than head plus body.
- Roof rat (Rattus rattus) — Climber of attics and trees in warm and coastal regions; tail longer than head plus body.
- Deer mouse (Peromyscus maniculatus) — Primary U.S. hantavirus carrier; lives throughout Washington and the interior West.
When rodents are busiest around Greenwich
Mice often invade homes or sheds in the fall.
DEEP's rodent certificate and model IPM plan name the Norway rat, roof rat, house mouse, deer mouse and white-footed mouse as the commensal rodents controlled in Connecticut.
Rules that apply in Connecticut
For context, nationally
- 1/4 inch (the width of a pencil) — Smallest gap a mouse can enter. CDC
- 890; 35% fatal; 94% west of the Mississippi — Hantavirus cases reported since 1993 (through 2023). CDC
Sources: Connecticut Department of Public Health; Connecticut Department of Energy and Environmental Protection, Pesticide Management Program; CDC; Pest Notes: House Mouse; Pest Notes: Rats; Hantavirus. Figures are quoted as the source prints them. How we check our sources
Simple ways to keep rodents away
- Keep grass short and remove tall weeds along fences.
- Fix leaking hoses, faucets, and irrigation heads.
- Fill gaps around pipes, cables, and AC lines with copper mesh.
- Cover dryer and exhaust vents with metal louvered covers.
- Store pet food and birdseed in sealed metal containers.
- Check crawlspace doors and vents for chewed openings each fall.
Shared basements and utility rooms are where rodent problems in rentals usually start. Landlords should walk them each fall and after every tenant turnover.Did you know?
Across Greenwich, the word rodent comes from the Latin rodere, which means to gnaw.
Across Greenwich, rats make ultrasonic chirps when they're tickled, which researchers compare to laughter.
Questions people ask
Is it safe to clean up droppings myself?
For small amounts, yes, with care. Wear gloves and spray the droppings with a bleach solution. Wait five minutes, then wipe up with paper towels. Never sweep or vacuum them dry.
Will rodents leave on their own?
Rarely. Once they've found food, water and a warm nest, they stay.
How long does rodent control take?
Most jobs take two to four weeks. That covers inspection, sealing and a few trap checks.
Are rats a bigger problem than mice?
Usually. Rats are bigger, chew more, and avoid new traps for days. They also tend to need more sealing work outside.
Can I just seal the holes myself?
Small gaps, yes. Use steel wool or copper mesh, then seal over it. Foam alone won't stop them. Rooflines and vents are harder, and that's where a pro helps.
How many homes in the U.S. have mice or rats?
About one in eight report them. The U.S. Census Bureau's 2019 American Housing Survey (AHS) found that 11.9% of occupied homes had seen rodents or evidence of them in the preceding year. A good Greenwich pro will walk you through how the plan matches what they found at your place.
Do wealthier homes get fewer mice and rats?
Not according to homeowner surveys. Fifty-two percent of U.S. homeowners with household incomes of $100,000 or more reported a rodent encounter at some point in their lives in a September 2022 Harris Poll for the National Pest Management Association (NPMA). Ask every Greenwich company you get a quote from what they tend to find in your part of town.
Are rodents a problem in Greenwich?
They're common here, as almost everywhere. House mice cause most problems.
Nearby cities
Related guides
Sources (11)
The facts in this article come from the public sources listed above. Every home is different, so ask the company you talk to about pricing and what’s included. Published by Rodent Exterminator · Updated September 11, 2026 · How we write these guides