How to Get Rid of Mice

The best way to get rid of mice is to do three things at once: take away their food, set a lot of snap traps along the walls where you see droppings, and seal the gaps they're using to get in. Most household infestations clear in one to three weeks this way; skipping the sealing step is why mice "keep coming back."

Below is the full plan, what each step looks like in practice, and the methods that waste your time.

Step 1: Confirm it's mice and find where they run

Look for 1/8-1/4 inch rice-shaped droppings, gnawed food packaging and greasy marks along baseboards. Check under the sink, behind the stove and fridge, in the toe-kicks under cabinets, the pantry, and the back of drawers. Droppings much larger than 1/4 inch point to rats, which need a different approach; see how to get rid of rats. Details: signs of mice.

Make a quick map. Where droppings are heaviest is where the traps go.

Step 2: Take away food and water

• Move cereal, rice, flour, pasta, pet food and birdseed into glass jars, metal tins or heavy plastic bins with tight lids.
• Pick up pet bowls at night.
• Wipe crumbs off counters and sweep under the toaster, stove and fridge.
• Use a trash can with a lid; take kitchen garbage out nightly.
• Fix dripping faucets and leaks under sinks.

This doesn't starve mice out quickly (they need very little), but it makes your traps the most interesting food in the room.

Step 3: Trap the right way

Snap traps are the cheapest, fastest and most reliable tool for a house. Electronic traps work too and are easier to empty. What matters is how you set them:

1. Use many. A common mistake is one or two traps for a whole house. Put out 8-12 in the kitchen alone, 2-3 feet apart along the walls where droppings are. More traps on night one means fewer nights.
2. Place them against the wall, trigger end touching the baseboard, or set two back-to-back parallel to the wall. Mice run along edges and walk right over them.
3. Bait small. A pea-sized dab of peanut butter or hazelnut spread pressed into the trigger. Oats, a sunflower seed or a bit of bacon work too. Cotton ball or dental floss on the trigger is good bait in fall (nesting material).
4. Set them in hidden spots too: behind the stove, inside lower cabinets, in the toe-kick space, in the attic along joists.
5. Check every morning, wear gloves, and move traps that haven't caught anything after 2-3 nights to new spots with fresh droppings.
6. Keep going for a week after the last catch.

Live-catch (multiple-catch) traps are an option if you want to get rid of mice humanely; check them daily, because trapped mice die quickly from stress and dehydration. Release far from homes, where local law allows. Glue boards catch mice but cause a slow death and also catch pets and birds; avoid them if you can.

More on trap types: mouse traps.

Step 4: Seal how they get in

Trapping removes the mice you have. Sealing stops the next ones. Do it during the same week you trap.

• Walk the outside at the foundation, and check under sinks, behind the washer and dryer, around the water heater, and in the garage.
• Anything a pencil fits into is big enough for a mouse.
• Stuff gaps with steel wool or copper mesh and cover with caulk, mortar or a foam sealant. Foam alone gets chewed through overnight.
• Cover vents and larger holes with 1/4-inch hardware cloth.
• Install door sweeps and fix the garage door seal.

The full checklist is on how to keep mice out.

Step 5: Bait stations, only if traps aren't enough

Rodenticides have a place, mainly outdoors around the foundation or in garages and crawl spaces where trapping is hard. Rules:

• Use only sealed, tamper-resistant bait stations. Since EPA's 2008 risk mitigation decision, products sold to homeowners must come as bait blocks in stations; loose pellets and second-generation anticoagulants (brodifacoum, bromadiolone and similar) are restricted to professionals.
• Common consumer actives include first-generation anticoagulants and bromethalin. They work in about 1-7 days, not instantly.
• Indoors, poisoned mice often die in walls, and the smell lasts one to three weeks. That is the most common regret in homeowner threads about mouse poison.
• Pets that eat poisoned bait or poisoned mice can be seriously harmed. Keep stations out of reach and record the product name.

If a pet or child eats rodent bait, call your veterinarian or Poison Control (1-800-222-1222) immediately.

Step 6: Clean up safely

Don't sweep or vacuum dry droppings. Ventilate, wear gloves, spray droppings and nests with disinfectant or a 1:10 bleach solution, wait 5 minutes, wipe up with paper towels and bag everything. Wash or toss nesting materials in drawers. This matters most with deer mice, which can carry hantavirus.

What doesn't work (and why)

• Ultrasonic repellers. Mice get used to the sound within days and it doesn't pass through walls or furniture. Lab and field tests have repeatedly failed to show lasting effect.
• Peppermint oil, dryer sheets, mothballs. Strong smells may move a mouse a few feet for a day. Mothballs at a concentration that would bother mice aren't safe in living spaces. See what smells do mice hate.
• Home remedies such as instant mashed potatoes, baking soda, or plaster and flour: inconsistent at best.
• One trap and waiting. Mice breed faster than one trap catches them.
• Expanding foam without metal. Chewed through.

How to get rid of mice in the walls and attic

Mice in walls come out to feed, so trap where walls meet floors in kitchens and closets, and under sinks where pipes enter. In the attic, set traps along rafters and joists and near the insulation where you find tunnels and droppings. Don't drill holes and pour poison into walls; that only leaves dead mice in places you can't reach. If you hear activity in many rooms or floors, it's time for a pro.

When to call a professional

Call a pest control company if you're still catching mice after two to three weeks, you can't find the entry points, you live in an apartment or condo (the source is often a neighbor or the building), or there's heavy contamination in an attic or crawl space. A typical residential rodent job runs roughly $200-$600 for inspection, trapping and basic exclusion, with full exclusion work sometimes $1,000 or more (approximate). Ask whether sealing is included. See rodent control.