How do I keep chipmunks out of my bird feeder?

The short answer

• Chipmunks are ground animals that climb when the pole lets them. ICWDM's own advice for feeders is to use designs that catch fallen seed, so the ground under the feeder is the first fix, not the last.
• A weight-activated feeder at a squirrel setting near 400 to 500 g does nothing: an eastern chipmunk weighs about 3 oz (85 g). Set near 70 g it shuts out adult eastern chipmunks, but a 1 to 2 oz least chipmunk weighs the same as a cardinal and no setting can separate them.
• Chipmunks climb, so baffle the pole as you would for a squirrel and clear the launch points beside it. A woodpile or stone wall beside the pole is both a chipmunk's home and its ramp.
• Feeding chipmunks their own pile elsewhere backfires. ICWDM puts eastern chipmunks at 2 to 4 per acre, rising to as many as 10 where food and cover allow.
• Chipmunks are not federally protected, but Missouri, Pennsylvania and Georgia all protect them under state law, and Georgia and Arkansas require a permit to kill them.

Take away the seed on the ground, then take away the climb. Chipmunks are ground squirrels: ICWDM calls eastern chipmunks "small, brown, ground-dwelling squirrels," and its advice for bird feeders is to "use feeders that capture fallen seed to reduce the amount that reaches the ground." So the fix is a clean drop zone, a catch tray the chipmunk cannot reach, and a baffled pole with nothing beside it to climb. A squirrel-proof feeder at its factory setting does not help, because an eastern chipmunk weighs about 3 oz and squirrel settings start near 400 g.

Two answers circulate. One says chipmunks climb into the feeder, so buy squirrel-proof hardware. The other says chipmunks only eat what falls, so ignore the feeder and sweep. Both are half right. ICWDM says chipmunks "mostly are ground-dwelling rodents" but "regularly climb trees," and its feeder page notes that squirrels and chipmunks "empty feeders quickly by climbing around or into the feeder." The spill is what brings a chipmunk in and keeps it. The climb is what it does once the easy food runs short and the pole allows it. Fix them in that order.

Why the chipmunk never leaves#

A chipmunk is not passing through. ICWDM gives a home range of up to 1/2 acre, but an adult only defends about 50 ft around its burrow entrance. If you see the same chipmunk at your feeder every morning, its burrow is almost certainly within that circle.

Look for the entrance. ICWDM describes a hole about 2 in across with no mound of soil, because the chipmunk carries the dirt off in its cheek pouches. The main tunnel runs 20 to 30 ft, with one or two food storage chambers. Those chambers are where your seed goes: Missouri Extension and ICWDM both say chipmunks cache food in their burrows, and ICWDM says they do it throughout the year. A chipmunk stuffing its cheeks under your feeder is filling a larder, which is why it seems to take more than one small animal could eat.

Burrows sit next to cover. ICWDM lists stumps, wood piles, brush piles and the edges of basements and garages, and it tells homeowners not to stack firewood against buildings and to remove or mortar stone walls. Penn State is specific about the feeder: "place bird feeders at least 15 to 30 feet from buildings" so spilled seed does not support chipmunks near the house. When you choose where the feeder goes, add that distance to the list.

Size settles which hardware works#

That table answers most of the "chipmunk-proof feeder" question. A weight-activated feeder left at a squirrel setting stays open under every chipmunk in North America. Turn it down until the ports close near 70 g, the setting the grackle routine uses, and an adult eastern chipmunk closes them. The cost is the Blue Jay, which weighs the same, and a Red-bellied Woodpecker right on the line.

A cage does no better. Our cage comparison notes that 2 in mesh admits chipmunks, and no source we read gives a mesh size that stops a chipmunk while still passing a chickadee. That leaves geometry and the ground.

The drop zone: what is on the ground is the problem#

UGA Extension lists chipmunk foods as grain, nuts and "seeds (sunflower or other seed in a bird seed mix)." Every seed that falls from your feeder is on that list. The work is cutting what falls and taking away what has already fallen.

Prices are 2026 United States big-bag benchmarks used as defaults in our seed cost calculator. Swap in your own and the ranking can change; the edible fraction and energy columns will not.

1. Switch to a seed with no hull. Sunflower hearts leave almost no ground layer. In-shell seed sends hulls and knocked-out kernels down together, and the chipmunk sorts the kernels out.
2. Drop the cheap mix. Birds flick milo, wheat and corn out of a birdseed mix to reach the sunflower, and chipmunks eat grain. Stop cracked corn outright from March to November.
3. Fit a catch tray above the baffle. ICWDM's instruction is to use feeders that capture fallen seed. A tray only works if the chipmunk cannot reach it, so it goes on the feeder or the pole above the baffle, never on legs on the lawn. Empty it every two or three days.
4. Rake every evening. Clear what is already down. The full routine, and how much seed accumulates under one feeder, is in seed waste and mess.
5. Pause ground feeding. A ground feeder or an open platform feeder is a chipmunk feeder. Take it in for the season, or put out only what the juncos and doves clear in an hour.

The same clean ground ends the night shift too. A chipmunk yard is usually a rat and mouse yard after dark, and they eat the same spill.

The pole: close the climb#

ICWDM says chipmunks regularly climb trees, so treat the pole the way you would for a squirrel. The baffle rule puts the top of the baffle at least 4.5 ft up, with 7 ft of clear space to the side. Those numbers are built against a gray squirrel, a far bigger jumper, and we did not find a source that gives a chipmunk's leap. The practical point is the launch points. A low stone wall, a stacked woodpile or a planter beside the pole is a chipmunk's cover and its ramp at once, and ICWDM wants the first two gone from around buildings anyway. Check your position with the baffle calculator.

Hang nothing below the baffle. A suet cage or a second hook under it is a step for a climbing chipmunk, and a feeder hung from a tree branch or a deck rail has no baffle at all.

The bag in the garage#

UGA Extension says chipmunks "will gnaw into bags containing dog food or bird seed," and ICWDM and Penn State both list bird seed not kept in rodent-proof containers among what they eat. A paper bag in an open garage is a second feeder you cannot see. Keep seed in a lidded metal can, as set out in storing birdseed.

What the law allows#

ICWDM says most states allow landowners or tenants to take chipmunks causing damage, and tells everyone to check local and state rules first. None of these sources says whether eating seed you put out for birds counts as damage. You do not need to settle that, because nothing on this page needs a trap. ICWDM also puts most chipmunk damage at under $200, and the damage it says warrants control is burrowing around stairs, patios and foundations.

If you do trap where it is legal, ICWDM's own precautions apply at a feeder: bait at the back of the trap and cover half of it so birds do not see the bait, and put snap traps inside a box with a 2 in entrance so songbirds cannot reach them.

Where this page stops#

• Repellents and scare devices are left out on purpose. ICWDM says no frightening devices are effective for chipmunks, and UGA says no repellents are registered for them.
• Nesting season adds a reason. ICWDM and Missouri Extension both say chipmunks take young birds and eggs. A fed chipmunk population sits right under your nest boxes during nesting season.

For the bigger climbers, the squirrel guide has the full baffle geometry, and the problems section matches every other symptom to its cause.

Frequently asked questions#

Will a squirrel-proof feeder keep chipmunks out?

Usually not as it comes. A weight-activated feeder at a squirrel setting closes for a 400 to 600 g gray squirrel, and an eastern chipmunk weighs about 3 oz, roughly 85 g, so it feeds freely. Turned down to close near 70 g, the shroud shuts under an adult eastern chipmunk but also under a Blue Jay. It cannot stop a least chipmunk at 1 to 2 oz, because that is cardinal weight. Cage feeders sized at 2 in mesh let chipmunks straight through.

Is it legal to trap or kill chipmunks raiding my bird feeder?

It depends on your state, and the rules are stricter than many people assume. Chipmunks are not protected by federal law, but ICWDM notes they may be protected by state and provincial rules, and that Georgia and Arkansas require a permit to kill nongame animals. Missouri and Pennsylvania protect chipmunks but allow control when they are causing damage. Check with your state wildlife agency before trapping. The feeder fixes on this page need no trap at all.

Should I put out a separate pile of food for the chipmunks?

No. It feels like a truce, but it is more food in the yard. ICWDM gives eastern chipmunk densities of 2 to 4 per acre, rising as high as 10 per acre where there is enough food and cover. A decoy pile raises the number of chipmunks working your yard, and every one of them also finds the spill under the feeder.

Do repellents or hot pepper keep chipmunks off the feeder?

Not reliably. ICWDM says repellents usually do not give a 100% reduction in damage and that taste repellents need repeated applications. UGA Extension states there are no registered repellents for chipmunks. ICWDM also says no frightening devices are effective for chipmunks. Hot pepper seed is the one repellent aimed at a feeder, and it does not change the fact that the animal can still reach the seed.

When do chipmunks stop coming to the feeder?

Late fall. ICWDM says chipmunks enter torpor with the onset of cold weather and stay relatively inactive through winter, living on the food cached in their burrows. Some come out on warm, sunny winter days, and most are back by early March. So the chipmunk season at a feeder runs roughly March to November, and the seed they carry off in fall is what feeds them through winter.

Sources and further reading

1. Chipmunks; Chipmunk Biology; Chipmunk Damage Identification Internet Center for Wildlife Damage Management Not federally protected, state rules vary, Georgia and Arkansas permits; eastern 5 to 6 in and 3 oz, least 3 to 4.5 in and 1 to 2 oz; burrows, torpor, home range, density, food caching, climbing, bird seed among nuisance losses
2. Chipmunk Damage Prevention and Control Methods Internet Center for Wildlife Damage Management Modify bird feeders and use feeders that capture fallen seed, harborage removal, 1/4 in hardware cloth, no effective frightening devices, repellent limits, trap placement that avoids birds
3. Controlling Chipmunk Damage (G9527) University of Missouri Extension 9 to 10 in long and about 3 oz, active early morning and late afternoon, cache food in burrows, protected under the Wildlife Code of Missouri but can be controlled when causing damage
4. Chipmunk Control (C910) University of Georgia Extension Diet includes sunflower and bird seed mix, gnaw into bags of bird seed, no registered repellents, all nongame wildlife protected in Georgia
5. Chipmunks Penn State Extension Place bird feeders at least 15 to 30 ft from buildings, quarter inch hardware cloth, protected by the Pennsylvania Game Commission but landowners may take them when causing damage