The fastest way to kill ants is to find and block their entry point, then use bait stations where you see them foraging

Ants enter apartments through cracks in walls, gaps around pipes, or openings under doors. Once inside, they leave a chemical trail that guides thousands more to food sources. Killing ants you see does not stop the colony — you need to interrupt the trail and poison the source. The most effective method is bait stations, which workers carry back to the nest, killing the queen and the colony that feeds them.

Start by cleaning up food debris, sealing containers, and wiping down surfaces where you see ant trails. Then place bait stations along the walls where ants are moving. Ants prefer the bait to other food, so they will find it. This takes three to seven days to show results, but it eliminates the problem at the source instead of just the ants you see.

If you share walls with other units, tell your landlord or building management when ready. Ants move between apartments through shared plumbing and electrical chases. Your neighbors may need treatment too, or the colony will straightforward move and come back.

Key Takeaways

  • Bait stations are more effective than sprays because ants carry poison back to the nest instead of just dying on contact.
  • You must find where ants are entering — usually cracks, gaps under doors, or openings around pipes — and seal those spots after treatment starts.
  • Notify your landlord or building management, because ants often move between units and may need building-wide treatment.
  • Clean up food sources and wipe ant trails while bait works, so ants do not establish new foraging routes.
  • Results typically appear in three to seven days, but complete elimination takes up to two weeks.

Finding where ants are entering your apartment

Follow the ant trail backward to its source. Ants move in a line, and that line leads to the entry point. Look along baseboards, under kitchen cabinets, around windows, and where pipes or cables enter the wall. Mark the spot with tape so you can find it again.

Common entry points are gaps under exterior doors, cracks in caulk around windows, holes where plumbing enters the wall, and spaces between baseboards and the floor. Shine a flashlight along these areas at night, when ants are most active. If you cannot find the entry point, place bait stations along the walls where you see the heaviest ant traffic — they will still work.

Using bait stations and baits correctly

Buy bait stations from a hardware store or online — brands like Terro, Raid, or Combat work well and cost between $5 and $15 per box. Place them directly on the ant trail, not scattered randomly. Ants must find the bait easily, or they will ignore it and keep foraging elsewhere.

Do not spray or clean the area around the bait station for at least three days. The ants need to find the bait, feed on it, and carry it back to the nest. If you spray the trail, you break the chemical signal and the ants will find a new route. Leave the stations in place for one to two weeks, even after you stop seeing ants — this ensures the queen and the entire colony are dead.

If you have pets or small children, use enclosed bait stations or place them in areas they cannot reach. The bait is toxic to animals too. Read the label and follow the placement instructions — some baits work better in kitchens, others in bathrooms or along walls.

Sealing entry points after treatment begins

Once you have placed bait stations, seal the entry point you found. Use caulk for cracks and gaps in walls, weatherstripping for gaps under doors, and foam sealant for larger holes around pipes. Wait until you see fewer ants before sealing — if you trap ants inside the wall, they may chew through drywall or find a new route into your apartment.

After three to five days of bait treatment, when ant traffic has dropped noticeably, seal the entry point. This prevents new ants from entering while the bait finishes killing the colony. If ants are coming from a shared wall or pipe, sealing your side helps but does not solve the problem if neighbors also have ants — that is why telling your landlord matters.

What to do if ants keep coming back

If ants return after two weeks, the colony may be in a neighboring unit or the entry point was not fully sealed. Check for new cracks or gaps, especially around pipes and electrical outlets. Ants are small and can find openings you missed.

Contact your landlord or building management and request a professional pest control inspection. They can identify whether the infestation is in your unit alone or spread across multiple apartments. Many leases require landlords to handle pest control, so this is their responsibility, not yours. Document when you first saw ants and what steps you took — this helps the pest control company understand the scope.

If your landlord does not respond, check your local tenant rights. Many jurisdictions require landlords to maintain habitable conditions, which includes pest control. You may be able to withhold rent, pay for treatment and deduct it from rent, or break the lease without penalty — but the rules vary by location and lease type.

Preventing ants from returning

Store food in sealed containers, especially pantry items like flour, sugar, and cereal. Ants can chew through paper and cardboard. Keep the kitchen clean — wipe down counters and stovetops daily, do not leave dirty dishes in the sink, and take out trash regularly. A single crumb is enough to attract a new colony.

Seal cracks and gaps as soon as you notice them. Caulk is cheap and takes minutes. The longer a crack stays open, the more likely ants will find it. Check around windows, doors, baseboards, and anywhere pipes or cables enter the wall.

If you live in a warm climate or an older building, ants may return seasonally. Keep bait stations on hand so you can treat when ready if you see a few ants — catching an infestation early is much faster than waiting until they are everywhere.

When to call a professional pest control company

If bait stations do not work after two weeks, or if ants are in multiple rooms and you cannot find the entry point, hire a pest control company. They have access to stronger treatments and can identify entry points you missed. Costs typically range from $150 to $400 for an initial treatment, depending on your location and the severity of the infestation.

Ask your landlord to pay for professional treatment — in most leases, pest control is the landlord's responsibility. If they refuse, check your local tenant laws. Some jurisdictions allow you to hire a professional and deduct the cost from rent, but you must follow specific procedures and give the landlord notice first.

Professional companies usually may provide their work for 30 days. If ants return within that window, they will retreat for free. This is a safety net if the infestation is severe or if ants are coming from neighboring units.

Frequently Asked Questions

How long does it take for bait stations to work?

You should see fewer ants within three to five days. Complete elimination usually takes one to two weeks. The bait needs time to spread through the colony and kill the queen. Do not assume the bait failed if you still see ants after a few days — this is normal.

Can I use spray and bait together?

No. Spray kills ants on contact but breaks the chemical trail they use to find the bait. If you spray, the surviving ants will find a new route and avoid the bait. Use bait alone for the first week, then spray only if you see ants in a different area of the apartment.

What if ants are in my walls and I cannot see them?

Place bait stations along the baseboards and in corners where walls meet the floor. Ants will find the bait even if the nest is inside the wall. If you hear rustling in the walls or see ants only at night, call a professional — the colony may be large and hard to reach with over-the-counter bait.

Do I need to tell my landlord about ants?

Yes. Ants often move between units, so your neighbors may need treatment too. Your landlord may also be required by law to provide pest control. Telling them also protects you — if the infestation gets worse and the landlord later claims you did not report it, you have a record of when you told them.

Will bait stations hurt my pets?

Bait is toxic to pets if eaten in large amounts. Use enclosed bait stations or place them in areas your pets cannot reach — under the sink, behind the refrigerator, or in a closet. If your pet eats bait, call your veterinarian or poison control when ready.