How to Get Rid of Grease Ants | A Complete Guide

Grease ants, also known as thief ants for their sneaky food-stealing habits, are notoriously persistent pests both indoors and outdoors. With a penchant for protein-packed and greasy delights like meats, cheeses, peanut butter, and oils, these tiny bandits easily adapt to various environments, setting up shop in ideal conditions.

When grease ant colonies grow large, they become a formidable foe, making elimination a challenging task. To successfully wage war against these crafty critters, it’s crucial to understand their behavior and tailor an ant extermination strategy accordingly.

How to get rid of grease ants? First, pinpoint their entryways and foraging paths. Disrupt ant pheromone trails by applying a vinegar-water solution. Strategically place borax or boric acid-based ant baits near these trails, targeting the entire colony. You can also use insecticide sprays, and dust. After eradication, monitor the treated area to avoid re-infestation.

Get ready to bid farewell to grease ants! In this section, we’ll arm you with a comprehensive guide to banishing these pesky intruders. We’ll explore the factors that attract grease ants and provide a detailed, step-by-step plan for evicting them from your domain. Let’s dive in!

Grease Ants | Information

Grease ants, also known as thief ants, are native to the United States and have staked their claim in Eastern, Western, and Central regions. They’ve even ventured into Northern Mexico, Southern Canada, and states like California, Mississippi, Illinois, Texas, and North Dakota. These tiny trespassers are true survivalists, able to thrive in harsh conditions.

Despite their small size, grease ants are mighty in their ability to set up colonies in a variety of locations. Indoors, they’re crafty enough to find homes in cracks, holes, under sinks, or behind cabinets and cupboards. Outdoors, they’ll burrow under rocks, in soil, beneath wood shavings, or wherever they discover an inviting environment.

What Are Grease Ants?

Grease ants belong to the genera Solenopsis, are named due to their fondness for greasy food. They are also known as thief ants because they build nests near shelters of other ants and steal their food, larvae, and pupae. Due to their smaller size, they can fit anywhere. 

Grease ants forage in large numbers and leave pheromone trails behind for other grease ants to follow. They mostly infest houses during the summer season. Grease ants are commonly confused with Pharaoh ants due to their tiny appearance.

Reproduction

Grease ant queens and drones have wings which help in the breeding process. They mate from July to late fall. Queens can lay up to 387 eggs each day. Eggs develop into adults in about 7 to 8 weeks. The newly hatched ants have lighter bodies that later turn darker (in 2 days) due to the deposition of chitin and pigments.

What Does a Grease Ant Look Like?

What Does a Grease Ant Look Like

Worker greases ants have a yellow to light or dark brown appearance and measure between 1.5 to 2.2 mm (or up to 1/16 inch). They have a smooth and shiny body, six legs, oblong abdomen, small compound eyes, and uneven thorax without spines. Antennae are divided into 10 segments, which end with bi-segmented antennal clubs.

The thief ants curl their body when they die. Grease ants are polygynous, which means they have up to eight queens (about 5 mm long) in each colony. The queen has a relatively thicker body and a large abdomen. Like other ants, they also have a caste system that includes queen, reproductive males and workers.

Are These Ants Attracted to Grease?

Grease ants are omnivorous and can eat anything including meat, honeydew-producing insects, fungal spores, dead animals, larvae, and pupae of host ants.

These ants travel a long distance in search of food and are attracted to your house mostly due to different food sources. They can eat both sweet and greasy food but prefer to feed on greasy foods such as olive oil, vegetable oil, peanut butter, fats, nuts, seeds, cheese snacks, dairy products, etc.

Do Grease Ants Bite?

Grease ants are not considered to be a potential threat, they do not bite or sting. Although, the well established colonies of grease ants can be annoying. Due to their smaller size, they can infiltrate food containers and packages and can ruin them.

As thief ants also feed on dead organisms, they can carry pathogens into your house and cause diseases like diarrhea, fever, or vomiting. Grease ants are the intermediate hosts for poultry tapeworms as they have the potential to carry tapeworm segments into their shelters.

What Kills Grease Ants?

Several ant killer sprays and baits are available commercially for getting rid of grease ant colonies. Professionals mostly use insecticide sprays, baits, or integrated pest management plan to control pests. However, ant baits or ant traps are considered to be the most effective ant killers.

The method with ant baits takes time but it kills the entire ant colonies including queens which eliminate the chances of re-infestation or survival of the colony. Other than commercial ant killers, natural or DIY homemade ant killers can also help to get rid of grease ants.

Sugar Ants vs Grease Ants

The primary difference between sugar ants and grease ants is their distinct behavior towards different food items. Sugar ants include a group of ants known for their fondness for sugar or sugar-based food items such as jams, jellies, cakes, juices, etc whereas grease ants (also called proteins ants) like to eat grease based or high protein food items.

Grease can also eat sugar-based food but they give preference to greasy food. Both of them are common household ants and are easily drawn to residential settings by following the food trails.

How to Get Rid of Grease Ants | Instructions

Grease ant’s extermination can be a very troublesome process especially when they invade your house or pantry. Their tiny size allows them to build nests in small cracks and other inaccessible areas.

In the following section, we have given a step by step guide for getting rid of grease ants and some additional tips on preventing their re-infestation.

Step 1: Ant Identification

Accurate identification of particular pests plays a key role in pest control. Grease ants are often confused with Pharaoh ant due to similarity in their size. The characteristics that distinguish Pharaoh ants from grease ants are different markings and body color. 

Pharaoh ants have three clubbed antennae whereas grease ants have two clubs on their antenna. Grease ants have a yellowish to brownish color, whereas Pharaoh ants have a reddish body with black markings at the abdomen.

Step 2: Inspection of Infested Sites

The next step is the inspection and investigation of infested sites. Look for small ants on your kitchen counters, cabinets, ants foraging on the floor, or near oil traces.

Grease ants build nests at remote and inaccessible sites and travel far from their nests for food. Follow their trails and monitor their nesting sites so you can, in the end, treat those areas with insecticide.

Step 3: Application of Insecticides

The selection of the best insecticide for the infestation at a particular site determines the end results. The pest control method suitable for indoor infestation may not work for outdoor grease ant’s eradication and the other way around.

Related: Do Dead Ants Attract More Ants? | The Play-Dead Phenomenon!

Indoor Pest Control | Ant Bait for Grease Ants

Use ant bait or ant traps for indoor eradication of grease ants. Find ant trails and their nesting sites and place the baits near trails, nests, and nearby access points of ants.

Some of our recommended baits for grease ants are:

1
Advance 375a Select Granular Ant Bait - 8 oz. ant Killer,ant Poison
  • Uses food attractant ants love
  • Works on wide range of ant species
  • Easy to apply
  • Treatments last several weeks
  • Weather resistant
2
TERRO T300B Liquid Ant Killer, 12 Bait Stations
  • Attracts & Kills – Kills common household ants including...
  • Kills the Ants You See & the Ones You Don't – As worker ants...
  • Works Fast – You should see a significant decrease in the...
  • Ready to Use – Place the bait stations, watch it attract ants,...
  • Use Throughout Your Home – Place stations near areas where...
3
Savitri Ant Gel Bait (4 x 30 Grams) by Atticus (Equivalent to The Leading Brand) - Indoxacarb Ant Control for Indoor and Outdoor Use
  • FAST, EFFECTIVE ANT TAKEDOWN: Savitri Ant Gel contains the same...
  • WHEN YOU HAVE ANTS, WE HAVE THE ANSWER: Don’t worry about...
  • EASY APPLY, EASY CONTROL: Our prefilled syringe makes easy work...
  • COMBAT THE COLONY: Formulated for infestation control, Savitri...
  • APPROVED TO USE NEARLY EVERYWHERE: Ants can hide almost anywhere,...
4
Maxforce Quantum 0.03% Imidacloprid Ant Control Liquid Bait with 10 stations, 120 Gram Bottle
  • Provides fast control of a wide variety of ant species
  • Clear, odorless formula allows for inconspicuous bait placements
  • May be used indoors and outdoors, residential or commercial,...
  • Lasts three months, unlike ant gel baits, which begin to lose...
  • Eliminates the entire colony, even those hidden in inaccessible...
5
Raid Max Double Control Ant Baits, 0.28 oz, 8 CT (1)
  • Two types of bait to attract and kill ants
  • After ants feed on the bait, they return to the colony and...
  • Population reduction can be expected within days, with the baits...
  • For household use: Closets, basements, attics, living areas,...
  • Child-resistant

Outdoor Pest Control

To treat the outdoor nesting sites, locate outdoor nests and ant trails to decide the required quantity of control solution or spray.

Directly treat the nests or infested sites with insecticide chemicals to eliminate grease ants. Remember to wear personal protective equipment (PPE) to avoid direct exposure to insecticide chemicals. Read the labels and follow product guidelines on the spray for effective pest control.

Some of the best insecticide sprays or control solutions for grease ants are the following:

1
Talak 7.9 F Bifenthrin Insecticide Concentrate (1 Gallon) by Atticus (Compare to Talstar) –– Indoor and Outdoor Insect Control
  • VERSATILE PARTNER, PROVEN EFFECTIVENESS: Talak 7.9 F contains...
  • ONE SOLUTION COVERS IT ALL: Our water-based formula can be used...
  • BROAD-SPECTRUM INSECT KILL: Talak 7.9 F targets more than 75...
  • GET THE WATER-BASED ADVANTAGE: Getting rid of bugs shouldn’t...
  • KILLS ON CONTACT, WORKS UP TO 3 MONTHS: Expect fast results with...
2
Mighty Mint Gallon (128 oz) Insect and Pest Control Peppermint Oil - Natural Spray for Spiders, Ants, and More
  • Safe
  • Extra Concentrated for Long-Lasting Protection
  • Natural Ingredients Proven Effective in the Real World
  • Large 1 Gallon Container
  • Powerful Essential Oil
3
Ortho Home Defense Insect Killer for Indoor & Perimeter2: With Comfort Wand, Kills Ants, Cockroaches, Spiders, Fleas & Ticks, Odor Free, 1.1 gal, 1 Pack
  • Ortho Home Defense Insect Killer for Indoor & Perimeter2 with...
  • KILLS BUGS INSIDE: Kills those annoying home-invading insects,...
  • KEEPS BUGS OUTSIDE: Creates a bug barrier that will kill bugs you...
  • NO STAINING OR STINK: This spray can be used indoors and out,...
  • WAND MAKES APPLICATION EASY: The Comfort Wand eliminates hand...
4
Wondercide - EcoTreat Ready-to-Use Outdoor Pest Control Spray with Natural Essential Oils - Mosquito, Ant, Insect Repellent, Treatment, and Killer - Plant-Based - Safe for Pets, Plants, Kids - 32 oz
  • KILLS & REPELS. A preventative and a treatment, this spray is a...
  • SPRAY & PLAY! Safe around cats, dogs and people of all ages, with...
  • TREATS UP TO 5,000 SQUARE FEET. A bug control spray that can be...
  • TREAT NATURE WITH NATURE. No artificial colors, fragrances. Made...
  • POWERED BY NATURE. Powered by cedar oil, our plant-powered...
5
Wondercide - Indoor Pest Control Spray for Home and Kitchen - Ant, Roach, Spider, Fly, Flea, Bug Killer and Insect Repellent - with Natural Essential Oils - Pet and Family Safe— Peppermint 32 oz
  • KILLS & REPELS. A preventative and a treatment, this...
  • PROTECT YOUR HOME. This versatile bug control spray is also an...
  • SAFE AROUND PETS & FAMILY WHEN USED AS DIRECTED. This spray is...
  • PLANT POWERED AND POWERFULLY EFFECTIVE. Using natural essential...
  • EASY-TO-USE. This biopesticide made with plant-based ingredients...

If you really want to kill ants even in a wider radius the best thing would be to combine insecticide sprays with ant baits. Monitor treated sites for 10 days and re-apply ant killers if needed. Take preventive measures to stop the re-establishment of grease ant colonies.

Step 4: Preventing Re-infestation

Remove all the factors that are attracting grease ants in your house or garden such as excess water, spilled food, leftovers, etc. Keep the kitchen floor and counters clean and do not leave the garbage overnight.

Tightly seal food containers, packages, and store them in the refrigerator. Clean pet feeders and pantries regularly. Seal all the cracks and holes that can be potential nesting sites of grease ants and apply sweeps, petroleum jelly, or caulk at the access point of ants.

Put ant repellent herbs or pots (garlic, sage, cinnamon, lavender, tansy, peppermint, etc) around your house. They will help to erase the ant trails and will prevent their entry into your house.

Home Remedies for Grease Ants | Natural Methods

Other than commercial ant killers, DIY natural insecticides can also help in the eradication of grease ants. This is an economical, eco-friendly, and non-toxic way to get rid of these pests. In the following section, we have shared the best DIY grease ant control remedies. Let’s begin!

Peanut Butter and Borax Bait

Peanut butter and borax bait can effectively eliminate grease ant colonies. To prepare peanut butter bait, take two teaspoons of peanut butter and mix it with four teaspoons of borax to make a paste.

You can also add honey to the paste for better results. Put the bait on a disposable container and place it near ant trails and nearby nests. If you want you can also stick these baits on the wall or cabinets with the help of tape.

Vinegar and Water

To make insecticide spray, mix equal parts of vinegar and water (1:1). Pour the solution into a spray bottle and directly apply it at the potential nesting areas and on the kitchen counters. This does not only kill ants but also keep them away.

Soap and Water

Soapy water is a natural insecticide, it can help to exterminate grease ants and several other pests. To prepare soapy water, take one part of dishwashing soap and mix it in two parts of water (1:2). Pour the solution in a spray bottle and treat the infested areas and access points of ants. Adding hot water to the soap can enhance the efficiency of this insecticide solution.

Peppermint Spray

Peppermint spray is a natural ant killer and repels the re-establishment of ants and other pests. To prepare peppermint spray, add 10 to 20 drops of peppermint essential oil in 2 cups of water and mix them together.

1
Mighty Mint - 16oz Insect and Pest Control Peppermint Oil - Natural Spray for Spiders, Ants, and More
  • Safe
  • Extra Concentrated for Long-Lasting Protection
  • Natural Ingredients Proven Effective in the Real World
  • Large 16oz Bottle
  • Powerful Essential Oil

You can also put a few drops of citrus oil or tea tree oil to increase the effectiveness of the spray.

Summary

Grease ants are also known as thief ants due to their habit of stealing food from neighboring ant nests. They can eat everything but prefer high protein, grease, or oil-based food items. Grease ants are one of the tiniest ants on earth which makes their eradication more difficult. They can fit everywhere and can establish colonies inside inaccessible cracks and holes in indoor and outdoor settings. 

Poor sanitary conditions and food can attract grease ants overnight in your house. Grease ants are often confused with Pharaoh ants due to their similar size. Accurate identification of the ant species helps to effectively get rid of them. To exterminate grease ants, you first need to inspect nesting sites and follow ant trails to select an effective ant eradication method we mentioned above. 

In case you are having a serious ant infestation, it would be best to call a professional pest control service. Click on the following link if you are interested, and you will get free quotes from the best ant exterminators in your area. Best of luck!

List of Sources

Extension and Outreach, Horticulture and Home Pest News, (2005). Grease Ants, Iowa State University of Science and Technology.

Plant & Pest Diagnostics, Thief ants, University of Arizona and Michigan State University.

Extension and Outreach, Horticulture and Home Pest News, (2005). Grease Ants are Still a Problem, Iowa State University of Science and Technology.

 Davis, (2011). Thief Ant – Quick Management Tips. UC IPM, Key to identifying common household Ants, University of California Agriculture and Natural Resources.