Getting chipmunks out of your garage comes down to three steps: remove them, seal their entry points, and eliminate what attracted them. Skipping any one of these means they’ll be back. Here’s how to handle each part effectively.
Confirm You’re Dealing With Chipmunks
Before you set traps or start sealing gaps, make sure chipmunks are actually the problem. Their activity pattern is the easiest giveaway: chipmunks are strictly daytime animals with a predictable schedule. You’ll hear them in the morning, silence during the hottest part of the afternoon, then activity again before dinner, and nothing at night. If you’re hearing noises after dark, you likely have mice or rats instead.
The sounds are distinctive too. Chipmunks move in bursts, a weighted scurry followed by a pause, then another run. You may also hear a rolling sound as they carry and drop nuts or seeds. Their droppings are noticeably bigger and more rounded than the small dark grains mice leave behind. And if you find a stash of seeds, nuts, or birdseed packed into a corner or behind stored boxes, that’s a clear sign a chipmunk has claimed your garage as a pantry.
Find Their Entry Points
The garage door is the most common entry point. Rubber seals along the bottom lose contact at the corners long before anyone notices, and a chipmunk only needs a gap of about two to three inches to slip through. Walk outside during daylight and look at each corner of your garage door from ground level. If you can see light coming through, a chipmunk can get in.
Check other spots too: gaps where utility lines or pipes enter the wall, cracks in the foundation, vents without screens, and any point where different building materials meet and have separated over time. Chipmunk entry holes look deceptively small, clean round openings roughly two to three inches across. Unlike other burrowing animals, chipmunks carry excavated dirt away in their cheek pouches, so there’s no telltale mound of soil to tip you off.
Trap and Remove Them
Live-catch wire mesh traps (the kind sold for squirrels or rats) work well for chipmunks. Peanut butter, sunflower seeds, and pumpkin seeds are all effective bait. Place traps along the pathways where you’ve seen chipmunks running, not just in random spots. Make sure the trap sits on a flat, stable surface. Any wobble when the chipmunk enters can trigger the door early and scare it off.
A technique that dramatically improves your catch rate is prebaiting. Wire the trap doors open and leave bait in and around the trap for two to three days without actually setting it. This lets the chipmunk get comfortable eating from this strange metal box. Once you see bait disappearing regularly, set the trap. The chipmunk has already learned to walk right in.
Check traps at least twice daily. A trapped chipmunk left in a hot garage can overheat quickly.
Know the Rules Before Relocating
Many people assume they can drive a trapped chipmunk to a park and let it go. In several states, this is illegal. New York, for example, prohibits releasing a trapped animal anywhere other than the property where it was captured. The reasoning: relocation spreads diseases like rabies and Lyme, stresses the animal, and dumps problems on someone else’s property. Other states have similar restrictions or require a permit. Check your state wildlife agency’s website before you trap anything. If relocation isn’t allowed, a licensed nuisance wildlife control operator can handle the removal legally.
Seal Every Gap
Removing chipmunks without sealing entry points is a temporary fix. New chipmunks will discover the same gaps within weeks.
Replace or adjust your garage door seal so it makes full contact with the ground at both corners, not just in the middle. For other openings, quarter-inch hardware cloth is the standard material. That mesh size is small enough to block chipmunks and mice. Galvanized hardware cloth resists rust, and vinyl-coated versions last even longer while blending in visually. Cut pieces to cover any gap, vent, or hole and secure them with screws and washers rather than just staples, which chipmunks can work loose over time.
Pay special attention to where pipes and wires enter the garage. Stuff steel wool into small gaps before covering with hardware cloth or caulk. Chipmunks chew through foam sealant easily, but steel wool and metal mesh stop them.
Remove Food Sources and Shelter
Chipmunks don’t move into a garage randomly. They’re looking for food and safe nesting spots. Birdseed is the single biggest attractant. If you store birdseed, pet food, grass seed, or garden bulbs in your garage, transfer them to sealed metal or heavy plastic containers. Even a partially open bag of sunflower seeds is an invitation.
Reduce clutter along walls and in corners. Stacked boxes, tarps, and piles of stored items create the sheltered spaces chipmunks nest in. Keeping items off the floor on shelving makes the garage less appealing and also makes it easier to spot new activity. If you have a woodpile against the garage’s exterior wall, move it at least 15 to 20 feet away. Chipmunks use woodpiles as cover and often burrow underneath them right against the foundation.
Repellents as a Backup
Repellents work best as a supplement to exclusion, not a replacement. Inside a garage, a few options can discourage chipmunks from lingering near entry points while you complete repairs.
- Cayenne pepper or chili powder: Sprinkle it along the base of garage walls and near gaps. You can also boil hot peppers in water, strain the liquid, add a drop of dish soap, and spray it around entry points. Reapply after rain or cleaning.
- Predator urine: Bobcat urine is marketed specifically for chipmunks and other small rodents. Fox and coyote urine also work. Apply near entry points. These need reapplication every few days, especially after rain or wind.
- Garlic and mint: Minced garlic mixed with chopped fresh mint leaves, spread near entry points, can deter chipmunks. The smell fades quickly indoors, so this works better around exterior gaps.
- Castor oil spray: Mix one to two tablespoons of castor oil with water and a drop of dish soap. Spray around burrow openings and along the garage’s foundation perimeter.
The common limitation with all repellents is durability. They wash away, dry out, or lose potency within days to weeks. Reapplication every few weeks (or after any rain) is necessary to maintain effectiveness. If you’ve properly sealed entry points and removed food sources, repellents become a minor insurance policy rather than your main defense.
Why Speed Matters
Chipmunks chew wiring, insulation, sheetrock, and stored items. The wiring damage is the most serious concern because it creates a genuine fire hazard. Their food caches cause secondary problems too: pounds of seeds packed into insulation attract pantry beetles and mice, and anything damp in a poorly ventilated space grows mold. Add urine and droppings to the mix and you may end up replacing insulation entirely rather than simply removing an animal.
A single chipmunk in the garage for a weekend is a nuisance. One that’s been nesting for weeks or months can cause damage that costs real money to repair. The sooner you act, the simpler and cheaper the fix.