Ants in Your Bed but No Food? Why They Come and How to Stop Them

"No food" also rarely means no food at all. A crumb under the bed, a sticky soda can, a pet bowl or a plant covered in aphids is plenty for an ant colony. The fix is to work out which of these you have, clean up the trail so others can't follow it, and close the way in.

Graphic: summary of this guide, made by our team from the cited sources.

What you see, and what it usually means

What you see	What it usually means	Do this first
A few ants wandering, no trail	Scouts looking for food, water or a nest site	Vacuum them up, wipe the area with soapy water, look for gaps near the bed
A steady line of ants	A trail to something they want, often water or hidden food	Follow the line both ways to find the entry point and the target
Ants coming out of a wall, outlet or baseboard	A nest inside a wall void or under the floor	Note the spot and call a licensed pro if it keeps happening
Large black ants at night, sawdust nearby	Carpenter ants, possibly nesting in damp wood	Check with a flashlight after dark, look for moisture problems
Winged ants at the window	A mating swarm from a nest in or near the house	Check they are ants, not termites (see below)
Small reddish ants that sting	Fire ants foraging indoors	Keep people and pets off the bed and call a licensed pro

Source: our table, built from the UC IPM, Penn State and Texas A&M fact sheets linked in this guide.

Why ants come to a bed when there is no food

1. Water. Bedrooms next to a bathroom, a leaky pipe, a sweating window or a damp wall attract ants. NPIC's prevention advice includes fixing leaky pipes and replacing moist or rotting wood.
2. Warmth and shelter. Several house ants nest inside walls, near hot water pipes or heaters. A bed against an outside wall can sit right next to that nest.
3. Weather. UC IPM notes ants may appear suddenly when other food sources become unavailable or the weather changes, and they come in to escape hot dry spells or flooding.
4. Hidden food. Crumbs between the mattress and frame, a drink by the bed, pet food or a snack wrapper in a bag are enough. Ants also follow the sweet honeydew that aphids, scales and mealybugs leave on house plants.
5. A nest in a potted plant. UC IPM tells readers to check potted plants as indoor nest sites.
6. Scouts. One or two ants on the sheets may be scouts. If they find nothing, they leave. If they find something, a trail follows.

Which ant is in your bedroom?

The species matters, because each one nests in a different place and the wrong treatment can make things worse. NPIC puts identifying the ant first.

Ant	Worker size	Where it nests indoors	Source
Odorous house ant	1/16 to 1/8 inch, smells rotten when crushed	Voids near moisture and warmth, termite-damaged wood	Penn State: Odorous House Ant
Pharaoh ant	About 1/16 inch, light yellow to reddish brown	Wall voids, under floors, behind baseboards, linens, light fixtures; likes warm spots near hot water pipes	Ohio State: Pharaoh Ant
Pavement ant	2.5 to 4 mm, dark brown to black	Under slabs and sidewalks; enters through cracks in slabs and foundation walls and leaves small sand piles	Penn State: Pavement Ant
Carpenter ant	1/4 to 1/2 inch, dark brown to black	Hollow areas of ceilings and walls, under insulation, often near wood kept wet by leaks or condensation	Penn State: Carpenter Ants
Red imported fire ant	1/16 to 3/16 inch, reddish or dark brown	Prefers to nest outdoors in soil, in mounds; workers forage indoors for food and water	Texas A&M: Managing Household Ants

Chart: our team's chart of the worker size ranges in the table above (Penn State, Ohio State and Texas A&M). Pavement ant millimeters converted to inches.

How to get ants out of your bed, step by step

1. Strip and wash the bedding, then vacuum the mattress seams, bed frame and floor around the bed. NPIC advises emptying the vacuum outdoors right away. You can find NPIC's full list in its ants fact sheet.
2. Wipe the trail with soapy water. Ants follow a scent trail. Wiping it breaks the path that leads other ants to the bed.
3. Follow the ants before you clean them all up. Watch where they come from: a baseboard gap, an outlet, a window frame, a crack in the floor. UC IPM lists bedrooms among the rooms ants invade and suggests inspecting along pipes.
4. Seal the entry point with caulk. UC IPM suggests petroleum jelly as a quick plug until you can caulk.
5. Remove the draw. Fix leaks, dry damp spots, keep drinks and snacks out of the bedroom, store food in sealed hard containers and rinse soda cans before they go in the bin.
6. Check house plants. NPIC suggests a water moat around potted plants so ants can't climb in.
7. Move the bed an inch or two away from the wall and keep sheets and blankets off the floor so ants can't climb straight up.

Do not spray the bed, sheets or mattress, and skip "natural" powders on bedding too. Any pest product, even a natural one, may only be used where its label allows. The label is the law.

Why spraying makes some ant problems worse

Spraying the ants you can see only kills the workers on the surface. Ohio State Extension says most of a Pharaoh ant colony stays hidden in the nest, and that a repellent pesticide can make the colony split and move to new spots, a habit called budding. Bug bombs don't reach the colony either.

Baits work differently. Workers carry the bait back to the nest and share it. UC IPM's ants guide says baits take 5 to 10 days to cut ant numbers and full control can take several weeks, and it recommends placing baits near ant trails and nest openings outdoors. It also warns that spraying ants indoors will not prevent more ants from coming in. Don't spray near baits, or the ants stop taking them. If you are working with a pro and see more ants for a few days, our guide on why you see more bugs after pest control explains what is normal.

Large black ants at night: check for carpenter ants

Carpenter ants are the ones to take seriously. Penn State says the workers usually come out at night, the nest may actually be outside, and indoor nests are often in hollow areas of ceilings and walls near wood kept wet by leaking pipes, tubs or showers. UC IPM's carpenter ant guide suggests inspecting after sunset with a flashlight, following the trails, and watching for sawdust-like frass or a faint rustling in the walls.

Winged ants in the bedroom: ants or termites?

Winged ants near a bedroom window mean a nest in, under or very close to the house. Texas A&M's guide to swarming insects indoors says ant swarmers have pinched waists and elbowed antennae, while termite swarmers have straight-sided bodies and long wings of equal length. Swarming usually lasts only one or a few days, and if you see no other ants, no further control may be needed. Termite swarmers indoors are different: unless one clearly flew in through an open window, Texas A&M advises contacting a termite control professional.

Bites but no ants? Rule out bed bugs

If you wake up with bites and never actually see ants, the culprit may not be ants at all. The EPA's guide to finding bed bugs says to check the piping, seams and tags of the mattress and box spring for rusty or reddish stains, tiny dark spots and shed skins.

Fire ants indoors: a safety issue

Fire ants sting. Texas A&M's fire ant site warns that fire ants foraging indoors can threaten people who are asleep or bedridden, and pets, and that whole colonies occasionally nest in wall voids or move into buildings during floods. If fire ants are reaching a bed, especially a baby's crib or the bed of someone who can't get up easily, call a licensed pest professional rather than treating it yourself.

When to call a licensed professional

• Fire ants anywhere inside the home.
• Large black ants or sawdust that point to carpenter ants in the walls.
• Tiny yellow ants spreading through an apartment or multi-unit building, which may be Pharaoh ants.
• Winged insects that might be termites.
• Ants still coming back after a few weeks of cleanup, sealing and moisture fixes.

A licensed pro can identify the species, find the nest and pick a treatment the label allows for a bedroom.