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Blog · October 2026

Mice in the walls: how to get them out

You cannot trap a mouse inside a closed wall. You can trap it where the wall opens into the room, and that is how mice in walls get caught. Here is how to find those spots, trap them, and seal the outside without locking anything in.

  • Find the exits
  • Trap where they come out
  • Seal in the right order
  • Skip the poison

In a hurry? Jump to the trap and seal order.

Start here

How do I get mice out of my walls?

The short answer

Trap them where the wall opens into the room, then seal the outside gaps so no new ones get in. Mice inside a wall still come out to eat, usually through openings around pipes under sinks, behind appliances and along gaps at the baseboard. Set snap traps right at those spots, along the wall, with the baited end touching the wall as the CDC advises. A house mouse normally travels an area only 10 to 30 feet across, according to University of California extension research, so the exit is usually close to the noise. Seal outside entry points with metal, but leave the inside exits open and trapped until the catches stop. Mice can fit through a 1/4 inch hole, the CDC says. Skip poison: UC IPM notes it often leaves mice dying inside the building. You are done after a full week with no catches and no fresh droppings.

Confirm and locate

First, confirm they are in the wall, and roughly where

Travel range from University of California extension research; gap size and the one-week standard from the CDC.

10 to 30 ftarea a house mouse normally travels
1/4 inhole a mouse can fit through
6 to 10 fttrap spacing where mice are active
1 weekwith no catches and no new signs

Light scratching and scurrying inside a wall at night is the classic mouse sound. If you are not sure whether it is mice, rats or something else, our attic and ceiling noise guide walks through what each one sounds like.

Then narrow it down. Noise near the floor in a kitchen or bathroom wall usually means mice are moving along plumbing. Noise high up, near the ceiling, often means they come down from the attic. Because a mouse stays close to its nest and food, the exit is rarely far from the sound.

Look on that side for droppings, chewed packaging and greasy smudges along pipes. Those marks point at the exit.

Find the exits

Where the wall void opens into the room

Every pipe, wire and duct that goes through a wall is a possible exit.

Under sinks

The gap where supply and drain pipes come through the back of the cabinet is the first place to look.

Behind appliances

Behind the stove, fridge and dishwasher, where water lines, gas lines and cords pass through the wall or floor.

Laundry and bath

Around washer hookups, the dryer vent and pipes behind toilets and tubs.

Outlets and switches

Mice climb wiring and plumbing lines inside walls. A loose plate or a gap around a box can be an exit.

Baseboards and corners

Gaps under baseboards, at cabinet toe kicks and where flooring meets the wall in closets and pantries.

Vents and returns

Gaps around duct boots and return grilles. Our mice in vents post covers that case.

Mice move up from crawl spaces along the gaps around plumbing and other utility lines, and they climb wiring and pipe runs inside walls, according to Oregon State University Extension. So start with every place a pipe, wire or duct passes through the wall near the noise.

Trap and seal order

Trap the exits, then seal in the right order

Outside first, inside last. That order keeps mice from dying in the wall.

  1. Trap every exit

    Put snap traps at each opening you found, close to the wall, with the baited end touching it. Mice run along walls, so that is where they meet the trap.

  2. Use enough traps

    UC research suggests spacing no more than about 6 to 10 feet apart where mice are active.

  3. Seal the outside

    Close outside entry points with metal so no new mice come in. Leave the inside openings alone for now.

  4. Check every morning

    Check traps daily, remove catches with gloves and reset. Mice stuck inside the wall have to come out to the trapped exits to eat.

  5. Wait for a quiet week

    Keep going until a full week passes with no catches and no new droppings, the CDC benchmark.

  6. Then close the inside

    Only now seal the gaps under sinks, behind appliances and at baseboards.

Which materials hold up and which mice chew through is covered on our exclusion and sealing page.

Poison and wall holes

Why not poison, and when a hole in the wall is worth it

A drywall patch is a small job. Guessing where to cut is not.

Poison seems easy when you cannot reach the mice. The catch is where they die. UC IPM notes that rodenticide use will often result in mice dying inside the structure, and trapping avoids the dead mouse odors that follow. Our dead rodent smell guide covers what that looks like.

SituationCut an access hole?
Mice active, exits found and trappedNo. Let the traps at the exits do the work.
A mouse stuck or tangled in one cavity for daysSometimes. A small hole, with a trap set at it, can give it a way out.
A strong dead animal smell in one wallOften. A small hole in the right spot is easier to patch than living with the smell.
You want to set traps inside the wallRarely worth it. Traps at the existing exits work better.

In an apartment or duplex, a shared wall means the mice may be coming from the unit next door, so sealing only your side is a short fix. Our renters guide explains who handles shared walls.

Mice in the walls

Want the exits found and the gaps sealed?

Call or send the form. We find where the mice get in and where they come out, seal with metal, trap what is inside and confirm with a full quiet week. The price is in writing before any work starts.

Is it working?

How to tell it is working

Fewer catches, then none, then a full week of nothing.

Expect a few catches early, then fewer. Noise inside the wall can get busier for a night or two as mice find their old route out blocked and look for another. That is not a bad sign.

If you are still catching mice after two weeks, new ones are probably getting in through a gap you have not found. More on how a full job runs is on our how rodent control works page.

  • Catches slowing down day by day
  • No fresh droppings at the exits or in cabinets
  • Scratching in the wall stops at night
  • Traps untouched for seven straight days
  • Inside gaps sealed only after the quiet week

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Straight answers

Mice in walls questions

How do I get mice out of my walls?

Find where the wall opens into the room, usually around pipes under sinks, behind appliances or at baseboard gaps, and set snap traps right there along the wall. Seal outside entry points with metal, leave the inside exits open and trapped until catches stop, then seal those last.

How do exterminators get rid of mice in walls?

They find the outside entry points and the inside exits, seal the outside, trap at the exits, and keep checking until a full week passes with no catches and no fresh droppings.

Will mice in the walls leave on their own?

Not while the wall is warm and food is close. Our post on whether mice leave on their own covers why.

Can I just seal the holes so they cannot get into the room?

Not first. Sealing the inside exits while mice are still in the wall can leave them stuck there. Trap the exits until the activity stops, then seal.

Is it safe to put poison in the wall?

We advise against it. Mice that eat poison often die inside the structure, and then you have a smell you cannot reach. Trapping lets you remove them.

How long does it take to get mice out of walls?

Often one to two weeks of trapping, plus the full quiet week to confirm. Longer if new mice keep coming in through an open gap.

Oxford & Lafayette County

Hearing it again tonight?

One call gets your inspection scheduled. Tell us what you heard and where. We seal first, trap second, and the six things in writing come standard.

Serving Oxford 38655, University 38677, Taylor 38673, Abbeville 38601, Paris 38949 and the rest of Lafayette County, Mississippi.

Rodent Control Oxford. Independent, rodent-only, local.