How to Get Rid of Ants in Your House: When to Call an Exterminator

Ants are the most common household pest complaint in the United States, and for good reason: a colony can send thousands of workers through a gap you cannot see. The key to getting rid of them is understanding what brought them in and where the nest actually is.

This guide explains why ants enter homes, how to recognize the common species, what prevention and DIY treatment can and cannot do, and when professional help is the practical choice. PestXpertz does not perform pest control; we connect homeowners with independent providers serving their area, subject to availability.

Why Ants Enter Homes

Ants come inside for the same three reasons they go anywhere: food, water, and shelter. Scout ants wander until they find something worth reporting — a crumb, a sticky spill, a pet food bowl — then lay a pheromone trail back to the nest so the rest of the colony can follow. That is why a single ant today becomes a trail tomorrow.

• Food

  Sugars, grease, crumbs, and unsealed pantry items are the main draw. Even residue inside a recycling bin can sustain a trail.

• Water

  Leaky pipes, damp wood, condensation, and overwatered houseplants attract moisture-loving species, especially in kitchens and bathrooms.

• Shelter and weather

  Heavy rain, drought, and temperature swings push outdoor colonies to relocate — sometimes into wall voids and foundations.

Common Household Ants

Identifying the species matters because nesting habits and effective treatments differ. A few of the most common indoor ants in the US:

• Odorous house ants

  Small, dark brown ants that give off a rotten-coconut smell when crushed. They nest in wall voids and under floors and are drawn to sweets.

• Pavement ants

  Dark ants that nest under sidewalks, driveways, and foundations, then forage indoors along baseboards.

• Carpenter ants

  Large black or red-and-black ants that tunnel through damp or damaged wood to build nests. They do not eat wood like termites, but their galleries can weaken structures over time, and sawdust-like shavings (frass) near woodwork are a warning sign.

• Pharaoh ants

  Tiny, light-colored ants that nest in warm, hidden indoor spots. Spraying them can cause the colony to split into several new ones, making the problem worse.

If you see large ants indoors, especially in spring, or find piles of frass, suspect carpenter ants and have the wood inspected — an outdoor colony may have established a satellite nest inside the house.

Why Ants Keep Coming Back

Spraying the ants you see rarely solves the problem, because the workers on your counter are a small fraction of the colony. The queen — or queens, since some species have many — stays hidden in the nest, producing replacements. Common reasons infestations return:

• The nest itself was never treated, so new workers keep foraging.
• Repellent sprays scattered the colony, and some species respond by splitting into multiple nests.
• The original attractants — moisture, food residue, entry gaps — are still in place.
• The colony is outdoors or in a wall void, and only the foragers were affected.

Lasting control means reaching the nest and removing the conditions that invited the ants in the first place.

Safe Prevention and the Limits of DIY

Prevention is the most effective thing a homeowner can do, and it is safe for kids and pets when done with basic sanitation and exclusion:

• Store food in sealed containers and wipe up spills and crumbs promptly.
• Fix leaks, reduce indoor moisture, and keep gutters and downspouts draining away from the foundation.
• Seal cracks around windows, doors, pipes, and the foundation with caulk.
• Trim tree branches and shrubs so they do not touch the house — they act as bridges for ants.
• Keep firewood and mulch away from exterior walls.

DIY baits can work for small, early infestations of common species, because workers carry the bait back to the nest. The limitations are real, though: baits fail when the wrong type is used for the species, when the colony is large or has multiple queens, and when the nest is inside a wall or under the slab. Over-the-counter sprays kill only the ants they touch and can make some infestations harder to treat later. Always follow the product label, and keep baits and sprays away from children and pets.

When Professional Ant Control Is Necessary

Consider calling a licensed professional when any of the following apply:

• Ants return within days or weeks despite cleaning, sealing, and baiting.
• You suspect carpenter ants — large ants indoors, frass, or activity inside walls or woodwork.
• Trails appear in multiple rooms or on upper floors, suggesting nests inside the structure.
• You cannot locate the nest, or it appears to be under the slab or inside a wall void.
• Someone in the home has health concerns that make prolonged infestations or DIY products risky.

Pest control licensing rules vary by state, so it is reasonable to ask a provider for their license details. Learn more about what service typically involves on our ant control page.

How Exterminators Identify and Treat Infestations

A professional visit usually starts with an inspection: the technician identifies the species, follows trails to entry points, and looks for moisture problems and nesting sites indoors and out. Identification drives the plan, because a bait that works for odorous house ants may do nothing for carpenter ants.

• Species-targeted baits

  Placed along trails and near nests so workers carry the active ingredient back to the colony, including the queen.

• Non-repellent treatments

  Applied to entry points and trails; ants pass through without detecting them and transfer the treatment to nestmates.

• Nest treatment

  Direct treatment of located nests, including wall voids and outdoor colonies near the foundation.

• Exclusion advice

  Recommendations on sealing entry points and correcting moisture issues so the problem does not restart.

Follow-up visits are common, especially for carpenter ants and multi-queen species. Ask the provider what the plan includes and how results are checked.

Frequently Asked Questions

Sources

• EPA — Controlling Ants
• University of Minnesota Extension — Ants
• UC IPM — Ants Pest Notes
• Penn State Extension — Carpenter Ants