Getting rid of rats in your house requires a combination of trapping, sealing entry points, and removing food sources. There’s no single trick that works on its own. Rats are intelligent, cautious animals that adapt quickly to their environment, so an effective plan attacks the problem from multiple angles at once.
Confirm What You’re Dealing With
Before you start setting traps, figure out which species you have. The two most common house-invading rats in North America are Norway rats and roof rats, and they behave differently enough that it changes your strategy.
Norway rats are the larger of the two: stocky, with small eyes and ears and a thick, hairless tail shorter than their body. They spend most of their time at ground level or underground, burrowing near foundations, under woodpiles, or in basements. Their droppings are roughly half to three-quarters of an inch long and rounded on the ends.
Roof rats are more slender, with large eyes and ears, a pointed snout, and a tail that’s often longer than their body. True to their name, they prefer elevated areas. You’ll find them in attics, rafters, trees, and along rooflines. Their droppings are similar in size but have pointier ends.
Both species leave the same general evidence: dark, pellet-shaped droppings along walls and in cabinets, greasy rub marks where fur contacts surfaces, gnaw marks on food packaging or wood, and scratching sounds at night. If you’re hearing activity overhead, you likely have roof rats. If the signs are concentrated near the ground floor, basement, or garage, Norway rats are more probable.
Seal Every Entry Point First
This step is non-negotiable. Rats can squeeze through a gap the size of a quarter. If you trap every rat inside but leave the entry points open, new ones will move in within days. Walk the exterior of your house and look for holes, cracks, and gaps around pipes, vents, utility lines, dryer exhausts, and where the foundation meets the siding. Any hole larger than a dime or crack wider than a pencil needs to be sealed.
Rats chew through most materials, so choose your sealants carefully. Steel wool stuffed into gaps works well because they can’t chew through it comfortably. Copper mesh is even more durable. For larger holes (rats chew openings two to three inches in diameter), combine steel wool or copper stuffing with cement, caulk, or expanding foam to hold it in place. Hardware cloth with small mesh can cover vents and larger openings. Avoid using foam alone, as rats can gnaw through it.
Don’t forget to check upward if you suspect roof rats. Gaps where rooflines meet, unsealed soffit vents, and openings around chimneys are common entry points for rats that climb.
Set Traps the Right Way
Snap traps remain the most reliable method for homeowners. They kill quickly, don’t involve poison, and let you confirm each catch. But rats are neophobic, meaning they fear new objects in their environment. This makes trap placement and timing more important than most people realize.
Start by prebaiting. Place unset traps with a small amount of food along the routes where you’ve found droppings or rub marks. Leave them unset for two to three days, reloading the bait each time it’s eaten. You want both adult and juvenile rats to get comfortable feeding from the traps before you arm them. Skipping this step is one of the most common reasons trapping fails.
For bait, use a pea-sized amount of something the rats are already eating if you can tell, or go with peanut butter, dried fruit, or nuts. Press the bait firmly into the trigger so rats can’t simply lick it off.
Place traps along walls, fence lines, or edges where rats travel. Rats stick to linear surfaces and rarely cross open spaces. Orient the trigger so it faces the wall, or set two traps side by side with the triggers facing away from each other. This catches rats traveling in either direction. Set multiple traps. There is never just one or two rats in an infestation, so three or four traps in a single area is reasonable, with more in rooms showing the most activity.
Check traps daily. Dispose of dead rats in a sealed plastic bag in your outdoor trash.
Why Poison Is Risky Indoors
Rodenticides (rat poisons) are available to homeowners, but they come with serious trade-offs that make them a poor first choice for indoor use. The most common type, anticoagulant poisons, work by preventing blood from clotting. A poisoned rat doesn’t die immediately. It can take several days, during which the rat may crawl into a wall void, ceiling, or ductwork and die in a spot you can’t reach. The smell of a decomposing rat inside a wall can last weeks.
The bigger concern is secondary poisoning. If a pet or child encounters a bait station, or if a dog or cat eats a poisoned rat, they’re at risk too. Single-dose anticoagulants are especially dangerous because a rat that keeps feeding after its first toxic dose accumulates far more poison than needed to kill it, turning the rat itself into a concentrated toxic package for any animal that eats it. Hawks, owls, and neighborhood cats are frequent victims of secondary poisoning from these products.
If you do use bait stations, place them only in locked, tamper-resistant stations that children and pets cannot open, and only in areas where you can retrieve dead rats before they decay in hidden spaces. For most homeowners dealing with an indoor infestation, snap traps are safer and more practical.
Cut Off Food and Water
Trapping alone won’t solve the problem if your house is still a buffet. Rats need only a small amount of food each day to sustain themselves, so even minor sources matter. Store all pantry food in glass or heavy plastic containers with tight lids. Move pet food into sealed bins and don’t leave bowls out overnight. Take garbage out daily and use cans with secure lids. Clean up fallen fruit if you have trees near the house, and pick up pet waste in the yard, which Norway rats will eat.
Fix leaky faucets and pipes, especially in basements and crawl spaces. Standing water in trays under houseplants, pet water bowls left out overnight, and condensation from HVAC units all provide water sources. Eliminating these makes your home significantly less attractive to rats looking for a place to settle.
Skip the Peppermint Oil and Ultrasonic Devices
Peppermint oil, mothballs, ammonia, vinegar, and ultrasonic plug-in devices are widely recommended online, but none of them work as a real solution. Peppermint oil’s scent dissipates quickly and has minimal measurable impact on rodent behavior. Mothballs contain naphthalene in concentrations high enough to repel moths and insects but far too low to affect rats. Ultrasonic devices may briefly startle rats, but they adapt to the noise quickly and the sound waves can’t penetrate walls or furniture, creating dead zones throughout the house.
Once rats have found a warm, safe shelter with food nearby, they will tolerate strong smells and annoying sounds rather than risk leaving. These products can mask the smell of an infestation or create a false sense of progress, but they don’t address the actual drivers: available food and accessible entry points.
Clean Up Safely
Rat droppings and urine can carry diseases, so cleanup requires some precautions. Never sweep or vacuum droppings. Sweeping launches dried particles into the air where you can inhale them, which is the primary transmission route for hantavirus and several other rodent-borne infections.
Open doors and windows and let the area ventilate for at least 30 minutes before you start. Leave the room during this airing-out period. When you return, put on rubber or latex gloves and spray the droppings and urine with a disinfectant or a bleach solution (one part bleach to ten parts water). Let it soak for five minutes. Then wipe everything up with paper towels and dispose of them in a sealed bag in your outdoor trash. After cleanup, disinfect any surfaces, tools, or items that may have been contaminated, and wash your gloves before removing them.
When to Call a Professional
A small infestation, a few rats with a single entry point, is manageable with DIY trapping and exclusion. But if you’re hearing activity in multiple areas of the house, finding droppings in several rooms, or still catching rats after two weeks of consistent trapping, the infestation may be larger than you can handle alone.
Professional rat extermination typically costs $150 to $600 for a standard job, which includes inspection, trap or bait station placement, and one or two follow-up visits. The initial inspection usually runs $90 to $150. For a medium infestation requiring multiple visits and sealing several entry points, expect $500 to $1,500 total. Large infestations involving extensive trapping, full-building exclusion, fumigation, and cleanup can run $1,500 to $8,000.
Timeline depends on severity. A small infestation can be cleared in a few days with traps or up to a week with bait stations. Larger infestations commonly take more than a month to fully eradicate. Sealing all entry points in a home typically takes up to three days of work. A professional can also identify entry points you’ve missed, which is often the difference between solving the problem and chasing it in circles.