Mice in the house this fall: what to do yourself and when to call a pro

When the nights get cold, mice and rats look for somewhere warm with food, and your house qualifies. The good news is that the first steps are ordinary household work: look for signs, close the gaps they use, and set traps where they travel.

This guide is built as triage. First you match what you see to what it likely means. Then you work through three jobs in order: Seal Up, Trap Up, Clean Up. Then comes a clear line for when to stop and bring in a licensed pest control pro. Everything here comes from the EPA and the CDC, and we link both so you can read the originals.

One note on the order. The EPA says to try identification and prevention methods first, so we start there and treat poison as a late option, not a starting point.

What's going on

Rodents are good at staying out of sight. The EPA notes that unless an infestation is severe, you might not see one at all, so a spotless kitchen proves little. You usually find them through the evidence they leave.

Here is a quick table of what each sign tends to mean and what to do next.

| Sign | What it likely means | Next move |
|---|---|---|
| Droppings around food packages, in drawers or cupboards, or under the sink | The EPA lists these as a sign of infestation. Mice are feeding and traveling here. | Note the spots. They are your trap locations. |
| Gnaw marks: chewed food packaging, or chewed holes in walls and floors | Also on the EPA's list of signs. Chewed holes may be an entry route or a path they have made. | Inspect the hole, then seal it (see Seal Up). |
| Shredded paper, fabric or dried plant material | The EPA says nesting material like this indicates rodents. | A nest means they are settled. Move to trapping soon. |
| A stale smell from a hidden area | The EPA lists stale smells from hidden areas as a sign. | Check closets, cabinet backs and spaces behind appliances. |
| Noises in walls or ceilings | Not on the EPA's sign list we are using, so treat it as a reason to look, not proof. | Search for droppings and gnaw marks near the sound. |
| Rub marks along walls | Also not on that list. A clue only. | Look for droppings or holes along the same path. |

One sign alone is a lead. Two or three together, say droppings under the sink plus a chewed hole, make a solid case.

What you can safely check or fix

Everything in this section is work a homeowner can do without a license. There is no electrical, gas or structural work in it. Do the steps in order.

Seal Up

1. Walk the outside of the house and look for gaps. The CDC says to search both indoors and outdoors to work out where the rodents entered.
2. Repeat the search inside, especially under sinks and behind appliances, where droppings were found.
3. Plug small holes with steel wool, as the EPA describes. It advises sealing holes both inside and outside.
4. Cut back the habitat near the house. The EPA recommends removing nesting sites such as leaf piles and deep mulch.
5. Put kitchen garbage in containers with tight-fitting lids.
6. If you feed birds, stop during an infestation or use only huskless items, per the EPA.
7. Turn compost so newly added food scraps are covered.

Sealing matters even if you plan to trap. The EPA's options page warns that released live-trapped rodents may return if entry points are not sealed, and the same logic applies here: more will follow through an open gap.

Trap Up

1. Choose traditional snap traps. The CDC recommends them for cutting down rodent numbers in and around the home. The EPA describes snap traps as lethal traps designed to kill rodents.
2. Skip glue traps and live traps. The CDC advises against them because frightened rodents may urinate, which raises illness risk.
3. Bait the trap with peanut butter or mutton fat, as the CDC suggests.
4. Set the trap with the baited end against the wall, forming a T.
5. Place traps in enclosed spots, such as the gap behind the stove or fridge and the rear of cabinets and drawers.
6. Keep traps and any bait where children and pets cannot get to them, per the EPA.
7. If you suspect rats, remember they are wary of new objects. The CDC says baiting traps before setting them helps rats get used to them.
8. Look at traps once a day, and get rid of any dead rodent right away, as the CDC directs.
9. Keep trapping until a full week goes by with no catches and no new signs.

Clean Up

1. Remove what drew them in: the food access, the open garbage, the nesting piles outdoors. The sealing and habitat steps above are the cleanup that prevents a return.
2. Dispose of trapped rodents promptly, the same day you find them.
3. Before handling droppings, nests or dead rodents, read the agency's current cleanup instructions directly. We do not restate protective gear or disinfectant steps here because we want them taken from the source, not paraphrased.

Where to stop and call a pro

Trapping is the homeowner's main tool, and it has an end point. The CDC says that if trapping fails, you should consider a poison bait station or seek professional help. Poison is where the risk rises, so this is the natural handoff.

The EPA says poison baits belong only in tamper-resistant bait stations, used according to the label. The CDC reserves poison or bait stations for persistent infestations and prefers EPA-registered products. If you are weighing that step, with children or pets in the home, or you are not sure you can place it safely, that is a reason to hand the job over.

Stop here: If you have kept trapping and sealing and the droppings, gnawing or nests keep appearing, or you are considering poison bait, call a licensed pest control pro instead of escalating on your own.

Other signals that it is time to call: you keep catching mice past the point where catches should have tapered off, you cannot find where they are getting in, or the evidence is in places you cannot safely reach. Check the company's license on your state's own license lookup before booking. Our directory links each listing to the state lookup.

What to tell the pro

A pro can work faster with a clear record. Gather this before the call:

• What you saw and where: droppings, gnaw marks, nesting material or smells, with the rooms and spots (under the sink, in drawers, behind the stove).
• How long it has gone on: when you first noticed signs, and whether new ones keep showing up.
• What you already did: which holes you sealed and with what, where traps sit, what bait you used, and how many catches, if any.
• Whether any poison is out: if you placed bait stations, say so, along with the product label.
• Entry points you found or suspect: inside and outside, matching the CDC's advice to check both.
• Outdoor conditions: leaf piles, deep mulch, compost, bird feeding or open garbage near the house.
• Who lives there: children, pets, and anyone with health concerns, since the EPA says traps and baits must stay out of reach of children and pets.

A short plan for this week

If you are not sure where to begin, start with the evidence. Mark where you find droppings, since those spots become trap spots. Then seal what you can find, set snap traps along walls in closed areas, and check them daily. Keep going until a full week passes with no catches and no new signs. If that does not happen, you have reached the point where the CDC suggests professional help.

Quick answers

What is the safest first step if I think I have mice?

Look inside and outside for how they got in, then seal holes, for example by plugging small ones with steel wool. The EPA says to try identification and prevention first.

Which traps should I use?

The CDC recommends traditional snap traps, baited with peanut butter or mutton fat and set against a wall. It advises against glue and live traps because frightened rodents may urinate, raising illness risk.

When do I call a licensed pest pro?

Call when trapping fails or signs keep returning, especially if you are considering poison bait. The CDC suggests a poison bait station or professional help if trapping fails.