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 Olympia, 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 Olympia 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.
- 2Chewed vehicle wiring or nesting under the hood.
- 3Rodent hair or droppings inside HVAC ducts.
- 4Greasy rub marks along baseboards, beams, and pipe runs.
- 5Dead-animal odor that appears and slowly fades.
- 6Scratching or scurrying sounds in walls or ceilings at night.
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.
- Deer mice can carry hantavirus.
Treatment options and typical costs
Inspection and Entry-Point Mapping
$75–$250
Expect a flashlight, a mirror, and a lot of crouching. In Olympia homes, the usual entry points are garage door corners, dryer vents, gaps around pipes, and roof-to-fascia joints.
- Time
- 60–90 minutes
- Best for
- Every job; nothing else works without it
Follow-Up Monitoring
$50–$150 per visit, or included in a plan
Ask what happens if activity returns during the monitoring period. Many re-trap and re-seal under the same agreement. Confirm first.
- Time
- 20–40 minutes per visit
- Best for
- Confirming the house stays clear after treatment
Snap-Trap Program
$150–$400 per visit
Snap traps remain the workhorse for rodents inside Olympia homes because a caught rodent is proof, not a guess. An Olympia pro sets many traps along walls and runways, then returns to check, reset, and remove.
- 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 Olympia 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.
Bathroom vanities hide the same plumbing gaps as the kitchen. A quick look with a flashlight shows droppings or rub marks long before you see a mouse.Which rodents live around Olympia.
They're small, curious and breed quickly. Norway rats are the other usual suspect. They burrow along foundations and enter low. Roof rats turn up in parts of Washington. They climb and come in high, through attics and rooflines. Deer mice live around Olympia too, mostly near open land and in sheds or cabins. They can carry hantavirus, so clean up their droppings carefully. House mice are the most common rodent in Olympia homes.
When they move in.
Check for gaps before then. Spring is breeding season. Small problems grow fast.
Fall is when rodents head indoors. Leaf piles against the foundation hide burrows and gaps, so clear them and walk the wall before the first cold snap.How they get into houses here.
Trim branches back from the roof. A lot of houses around Olympia have crawl spaces, and crawl vents and access doors are the usual way in. Check that vent screens are intact. Make sure the crawl door closes tight. Look for gaps where pipes and wires pass through the floor. Homes from Olympia out to Tacoma and Federal Way share the same weak spots, so the checklist below works across the area. For roof rats, check soffit vents, gable vents and eaves.
A year of rodents in Olympia.
- Fall: mice move indoors as nights cool. Seal gaps in September. - Winter: with lows near 34°F in Olympia, check the attic, garage and pantry for droppings. - Spring: breeding season. Act on any sign quickly. - Summer: with highs around 78°F in Olympia, rodents look for water. Fix drips and leaks.
Mice or rats?
- 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. - Rub marks: rats leave greasy smudges along walls and beams.
Sealing small gaps yourself.
- 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. - Check your work: daylight through a gap means it isn’t sealed.
Cleaning up droppings safely.
- 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. - Wash your gloved hands, then your hands.
What happens at an inspection.
They check the foundation, vents, rooflines and utility gaps. Inside, they check the kitchen, garage and attic. They'll also check the crawl space. You should come away with a list of entry points. Photos help. Most inspections take about an hour. The inspector walks the outside first.
Rodents in the car.
Clear birdseed and pet food from the garage. Mice and rats nest in engine bays and chew wiring. Park in a closed garage when you can. Check the air filter box for nesting.
Bird feeders and rodents.
Store seed in a metal can with a tight lid. Spilled seed feeds mice and rats. Use a seed tray and sweep up spills. If rodents show up, bring feeders in at night.
Questions to ask before you sign.
- 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? - Will you use poison inside? (Ask them not to.)
Rodents by the numbers.
Across Olympia, what actually matters is a walk-through: where the droppings are, how the rodents are getting in, and how large the colony is. Across Olympia, those three findings — species, entry points, and scale — are what a quote should be built on, not a regional average. Across Olympia, 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
- Age of the home and condition of the foundation.
- Whether sheds, garages or other outbuildings are included.
- Outdoor pressure from creeks, alleys, or restaurants nearby.
- Follow-up visits included versus billed separately.
- Sewer line inspection if rats are entering underground.
- Crawlspace or slab; crawlspaces add labor.
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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
Seal small gaps with steel wool and sealant. Rooflines, vents and attics are harder. That's where a pro's sealing work pays off. Start tonight with snap traps along the walls. Bait them with peanut butter. Store food in sealed bins.
Rodents in Olympia
In Olympia's neighborhoods, woodpiles, fences, bird feeders and gardens draw rodents close to the house. A typical home in Olympia is worth around $480k, and chewed wiring or soiled insulation can get expensive. Olympia gets about 51 inches of rain a year, and heavy storms flood burrows, which pushes rats toward buildings. Winter lows average around 34°F in Olympia, and that cold is what sends mice looking for a way in.
Local research
Rodents in Olympia, WA: what the public record shows
Before you compare quotes, it helps to know which rodents actually live in Washington, when they are busiest around Olympia, and what the state figures look like. Everything below links to the agency or university page it came from.
Rat litter size
Old World rats are not regulated; killing is unrestricted.
WDFWRat entry hole
Footprint about 1/2 inch long; incisors grow 5 inches a year.
WDFWRodent species recorded in Washington
- 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 Olympia
Year-round; roof rats in Puget Sound attics.
Rules that apply in Washington
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: Hantavirus; WDFW; CDC; Pest Notes: House Mouse; Pest Notes: Rats. Figures are quoted as the source prints them. How we check our sources
Simple ways to keep rodents away
- Seal the gap where the garage slab meets the wall.
- Seal every gap larger than a quarter inch with metal mesh.
- Check crawlspace doors and vents for chewed openings each fall.
- Take bird feeders down or use catch trays for spilled seed.
- Inspect vehicle engine bays if parked near fields or woods.
- Declutter garages and attics to remove nesting cover.
Before you call, sketch where you have seen droppings or heard noise and measure any gaps you found. It makes the first visit faster and the quotes comparable.Did you know?
Across Olympia, rats are strong swimmers and can tread water for a long time, which is why they sometimes travel sewer lines.
Male house mice sing ultrasonic songs that humans can't hear.
Questions people ask
Are snap traps better than poison?
Poisoned rodents can die inside walls and smell for weeks. Bait belongs in locked stations outside. Indoors, usually yes. Traps let you confirm the catch and remove it.
Are rats a bigger problem than mice?
Rats are bigger, chew more, and avoid new traps for days. Around Olympia, roof rats often nest in attics, so check the roofline too. Usually.
Do ultrasonic repellers work?
It doesn't pass through walls either. Sealing and trapping work better. Not reliably. Rodents get used to the sound within days.
Do I need to replace attic insulation?
Light activity can often be cleaned up. Ask the inspector to show you before you agree to replacement. Only if it's heavily soiled or flattened by nesting.
What should be in a rodent control quote?
It should say what happens if they return. Cleanup should be listed separately. Entry points, sealing materials and the number of trap visits.
How common are rodent problems in U.S. homes?
If you have found a mouse in the house, you are in a large club: 49% of U.S. homeowners in a 2022 NPMA/Harris Poll reported a rodent encounter at some point in their lives. Very common.
Do wealthier homes get fewer mice and rats?
homeowners earning $100,000 or more reported a lifetime rodent encounter in the 2022 NPMA/Harris Poll, no lower than homeowners overall. Before work starts in Olympia, ask how many visits are included and what happens if the rodents come back. Not according to homeowner surveys. Across Olympia, rodents do not check tax returns: 52% of U.S.
Are rodents a problem in Olympia?
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