Pest control companies primarily use non-repellent liquid insecticides, gel baits, granular treatments, and insecticidal dusts to eliminate ants. The key difference from store-bought products isn’t just stronger chemicals. It’s the strategy: professionals use products ants can’t detect, so workers carry the active ingredient back to the colony and spread it to the queen.
Non-Repellent Liquid Insecticides
The backbone of most professional ant treatments is a non-repellent spray applied around your home’s exterior perimeter, entry points, and sometimes interior baseboards. “Non-repellent” is the critical distinction here. Over-the-counter sprays typically use pyrethroids that ants can smell and avoid, which just redirects them to a different entry point. Non-repellent products are odorless and invisible to ants, so they walk through the treated area without knowing it.
The most common active ingredients in these sprays are fipronil, a phenylpyrazole that disrupts the insect nervous system, and dinotefuran, which the EPA has granted reduced-risk status for indoor use. These chemicals work through contact and transfer: an ant walks through the treated zone, picks up a microscopic amount, then passes it to nestmates through normal grooming and food-sharing behavior. This chain reaction is what eventually reaches the queen and collapses the colony, rather than just killing the few ants you can see.
Dinotefuran-based products are particularly common for indoor use because they’re odorless, mix clear in water, and are approved for food-handling establishments like restaurants. Your technician will typically spray along baseboards, around door frames, window sills, and any cracks where ants are trailing.
Gel and Liquid Baits
Baiting is the other major tool in a professional’s kit, and it works on a simple principle: give ants something they want to eat, laced with a slow-acting poison they’ll share with the colony before it kills them. Professionals use commercial-grade gel baits applied in small dots near ant trails, behind appliances, inside wall voids, and in other areas where ants are active but the bait stays out of your way.
The active ingredients in professional baits vary, but they’re formulated to kill slowly enough that foraging workers survive long enough to carry the bait back to the nest. This is where species identification matters. Different ants prefer different foods depending on what the colony needs at that moment. Some species crave sugary baits, others go for protein or grease-based formulations. A professional will often set out more than one type to see what the colony accepts.
Bait stations also come in liquid form for species that prefer to drink rather than eat solid gel. Your technician may swap bait types if the first round doesn’t get picked up within a few days.
Granular and Perimeter Treatments
For outdoor control, pest companies use granular insecticides broadcast across your lawn or applied in a band around your home’s foundation. These granules are watered in or activated by rain, creating a treated zone that ants cross on their way inside.
One professional-only product worth noting is a fipronil-based granule applied at about 2 pounds per 1,000 square feet that provides fire ant control for a full year with a single application. It can only be applied by a licensed commercial applicator, and while it’s more expensive than standard treatments, the year-long residual makes it cost-effective for properties with persistent fire ant problems.
Broadcast treatments cover the entire yard and work as contact insecticides. Liquid drenches target individual mounds directly. For a mound drench, the goal is to saturate the colony with 1 to 2 gallons of diluted insecticide, starting with a ring around the outside of the mound before pouring the rest over the top. This prevents the queen from escaping out a side tunnel before the liquid reaches her.
Dust Treatments for Wall Voids and Nests
When ants are nesting inside your walls, attic, or structural wood, professionals use insecticidal dust injected directly into the nest cavity. This is especially important for carpenter ants, which hollow out wood to build their colonies and can cause real structural damage over time.
Carpenter ants are notoriously difficult to control with baits because they eat such a varied diet that they often ignore bait products. Spraying visible workers is also mostly useless, since the colony stays largely unaffected even if you kill every ant you can see. The effective approach is locating the main colony and any satellite colonies, then applying dust directly into the nest through small drilled holes or existing gaps. Professionals use specialized applicators to puff dust deep into wall voids, behind insulation, and into tree trunks or branches where colonies sometimes establish.
This is one area where hiring a professional makes the biggest difference. Finding a carpenter ant nest inside a wall requires experience reading the signs: frass piles (sawdust-like debris the ants push out of their galleries), faint rustling sounds, and moisture-damaged areas where colonies prefer to settle.
What Makes Professional Products Different
Some of the products professionals use contain the same active ingredients available at hardware stores, just at different concentrations or in formulations designed for commercial application equipment. But certain products are classified as restricted-use pesticides by the EPA, meaning only licensed applicators can purchase or apply them. These restrictions exist because the products require specific training to use safely and effectively.
Beyond the chemicals themselves, the real advantage of professional treatment is the approach. A technician will identify the ant species, locate or estimate where the colony is nesting, choose products and placement based on that species’ feeding preferences and behavior, and combine multiple methods. Spraying a can of raid along your baseboards kills the ants it touches. A professional treatment is designed so the ants you never see, including the queen, are eliminated through the ones you do.
How Long Professional Treatments Take to Work
Most professional ant treatments don’t produce instant results, and that’s by design. Non-repellent sprays and baits need time to spread through the colony via contact transfer and food sharing. You’ll typically see a reduction in visible ants within the first week, but full colony elimination can take two to three weeks depending on the size of the colony and the species.
It’s normal, and even a good sign, to see increased ant activity in the first day or two after treatment. That means ants are actively moving through treated zones and picking up the product. If you’re still seeing heavy trails after three weeks, most pest control companies will retreat at no extra charge as part of their service guarantee.
For carpenter ants specifically, treatment may involve multiple visits. Because these ants often maintain a main colony outdoors and several satellite colonies inside a structure, the technician may need to locate and treat each one separately. Ongoing monitoring matters here, since a single missed satellite colony can rebuild the infestation over time.