How to get rid of mice in the house: trap fast, seal for good

Step by step: how to get rid of mice in the house

Safety first. Wear gloves to handle traps, mice, droppings and nests, and wash your hands afterward. Never sweep or vacuum droppings; wet them with disinfectant first. If you use rodenticide, use only ready-to-use, tamper-resistant bait stations placed out of reach of children, pets and wildlife, and follow the label.

1. 1

   Find where the mice are active

   Look for droppings (dark, rice-sized pellets), gnaw marks, shredded paper nests and greasy smudges along walls. Check under the kitchen sink, behind the stove and fridge, the back of the pantry, drawers, closets, the garage and the basement. Mice are most active at night, so a musky smell or scratching then is also a clue.

2. 2

   Take away food and nesting material

   Move cereal, grains, snacks, pet food and birdseed into glass or hard plastic containers with tight lids; mice chew through bags and cardboard. Wipe up crumbs, keep trash in a lidded can, and feed pets only what they eat at one meal. Clear piles of paper, cardboard and fabric scraps mice use for nests.

3. 3

   Set plenty of snap traps along walls

   Set traps where you found droppings, with the trigger end against the wall so mice run over it. Use a pea-sized dab of peanut butter, or a bit of cotton ball or dental floss, which nesting females want. Space traps no more than about 10 feet apart in busy areas, and set pairs an inch or two apart where mice travel.

4. 4

   Check and reset traps every morning

   Wearing gloves, drop each caught mouse into a plastic bag, spray it with disinfectant, seal it, and put it in the outdoor trash. Reset the trap in the same spot. If a trap catches nothing for 3 nights, move it closer to fresh droppings.

5. 5

   Seal the gaps they are using

   Mice can squeeze under a gap 1/4 inch tall. Pack coarse steel wool or copper mesh into gaps around pipes, wires, gas lines and vents, then caulk over it. Cover larger openings with hardware cloth and patch foundation cracks with mortar. Do not rely on foam, rubber or wood, which they chew through.

6. 6

   Close up the outside of the house

   Fit door sweeps and check that doors, windows and screens close tightly, including the garage door seal. Trim shrubs and vines back from the walls, since mice climb well, and move firewood and clutter away from the foundation.

7. 7

   Clean up droppings and nests safely

   Open windows and air out the area for 30 minutes first, as California’s Department of Public Health advises. Spray droppings and nests with a fresh 10% bleach solution (1 part bleach to 9 parts water) or a labeled disinfectant until soaked and wait at least 5 minutes. Wipe them up with paper towels, bag everything, then disinfect the surfaces and wash your gloved hands before removing the gloves.

8. 8

   Keep a few traps out as a warning

   When a week goes by with no catches and no fresh droppings, the mice are gone. Leave two or three traps along walls in the garage, basement or under the sink, and check them weekly, especially in fall.

Which mouse control method works best?

Snap traps are the best first step for most homes, and sealing entry points is what makes it permanent. UC IPM calls trapping the preferred method in homes where only a few mice are present and exclusion the most successful and permanent form of control. It also notes that high-frequency electronic devices are not effective.

How many mice are in your house?

If you see one mouse, assume there are more. House mice breed fast: UC IPM notes a female can have 5 to 10 litters a year of 5 or 6 pups, and young mice can breed at 5 to 6 weeks old. They eat many tiny meals a night and seldom travel more than 30 feet from their nest.

The EPA notes you may never see a mouse unless an infestation is severe, and lists droppings around food packages, in drawers and under the sink as a key sign. Fresh droppings are dark and soft; old ones are gray and crumbly. Set more traps than you think you need: the National Pesticide Information Center advises introducing traps early, estimating how many you need from the suspected number of mice, and setting backups because some traps will fail.

Is mouse poison safe to use at home?

Mouse poison can work, but it is the riskiest option in a home with kids or pets. The EPA restricts consumer rodenticides to ready-to-use bait stations with block or paste bait; loose pellets are no longer allowed in consumer products, and the strongest anticoagulants are sold only to professionals.

• Place stations along walls where mice travel, out of reach of children and pets, and follow the label for indoor or outdoor use.
• Never take bait out of the station or scatter it.
• Expect mice to die out of sight, sometimes inside walls, which can cause odor.
• If a child or pet may have eaten bait, call Poison Control (1-800-222-1222) or your vet right away and have the label with you.

If you hear mice in walls or ceilings, see mice in walls and ceilings, and for safe cleanup see how to clean up mouse droppings.

When to call a pest control professional

Call a licensed pest control professional if you are still catching mice after two weeks, if you find droppings in several rooms or floors, if you suspect rats (bigger droppings, louder noise, burrows outside), or if you cannot safely reach the attic or crawl space. A pro can also do exclusion work on the outside of the house.

Cleanup after an infestation needs care, since mice carry diseases. California’s Department of Public Health advises airing out the space for 30 minutes, soaking droppings with disinfectant or a fresh 10% bleach solution for at least 5 minutes, and never sweeping or vacuuming them.

Mistakes to avoid

• Setting two or three traps for a whole house instead of a dozen or more.
• Putting too much peanut butter on the trigger, so mice lick it off without setting it off.
• Placing traps in the middle of the floor instead of against walls.
• Plugging holes with expanding foam or wood, which mice chew through.
• Releasing live-caught mice outside, where they often find their way back.
• Vacuuming droppings, which can put viruses in the air.