Thief Ant


Actual Size: 1.5 to 2.2 mm

Characteristics: Brown to yellow in color.


  • Will nest near other ants, then steal the food and larvae from their neighbor
  • Often mistaken for Pharaoh ants
  • They prefer greasy foods, meat and dairy.

Thief Ant Overview

Thief ants are distributed throughout much of the eastern U.S. and get their name from their habit of nesting near other, larger ants, then entering their nest to steal food and prey upon larvae. Colonies tend to be smaller than other species but can contain multiple queens and several thousand workers. Outdoors, they feed on rodents and insects. Also known as grease ants, thief ants enjoy feeding on potato chips and other greasy household foods.

Thief Ant Habitats

Outdoors, nests are found in exposed soil, under rocks, or in rotting wood. Indoors, they nest in woodwork and masonry. Thief ants enter structures through cracks in the foundation or small openings in woodwork during hot weather. They use electric wires in wall voids to move from one room to another. These ants forage in trails throughout a home or building seeking greasy foods, protein, and dairy. Thief ants are commonly found in kitchen areas of homes.

Thief Ant Behaviors, Threats or Dangers

Thief ants have the ability to bite, though they rarely do. Thief ants are considered a danger as they feed on dead rats, mice, and insects. When they enter homes, they may be carriers of disease-producing organisms and contaminate food sources as they forage. Thief ants set rails inside cabinets, on walls, along baseboards and along tree branches and shrubs. Due to their small size, they are able to forage into packaged foods.

Thief Ant Prevention

To prevent thief ants, look for trails along walls, baseboards, in closets, cabinets, sinks, window sills and under outdoor items such as rocks or boards. Sponge invaders with soapy water when you see them and dispose of in a trash bin. Keep your kitchen clean, quickly wiping up greasy spills. Pick up pet food and clean area after feeding. Trim back trees, and shrubs from the exterior of your home as thief ants will use them to access your home. Seal cracks in your home’s foundation, caulking gaps around windows and doors. Replace damaged window and door screens and install door sweeps on exterior doors.