What Do Carpenter Ants Look Like?

When it comes to spotting a carpenter ant, size isn’t the only thing that sets them apart—but it’s a good place to start. While they aren’t the biggest ants on earth, they are the heavyweights of the ant world here in North America. Once you know what to look for, you can easily identify them. So what do carpenter ants look like exactly?

We’ll break down their appearance from head to toe so you can immediately pick them out of a lineup.

One of the first clues you’ll have that you’re looking at a carpenter ant is their size. While most ants measure between 1/16 and 1/8 of an inch, carpenter ants can grow much larger. Workers range from 1/4 inch to 1/2 inch in length, and the larger “major” workers, often called soldiers, are noticeably bulkier with bigger heads.

The queen is in a size class of her own, stretching up to 5/8 inches. Carpenter ants can be seen from several feet away, without squinting. When you see one for the first time, it’s hard not to notice how substantial they look compared to those tiny sugar ants that raid your pantry.

Many people think carpenter ants are only black because the black carpenter ant is the most common species in the U.S., but depending on the species, carpenter ants can also be:

• Reddish-brown
• Black with red thoraxes
• Completely brown
• Bicolored with darker abdomens and lighter heads

Fun Fact: Black carpenter ants aren’t always all black. They will often have reddish legs or red “highlights”.

So the color alone won’t confirm you’re looking at a carpenter ant, but it’s one piece of the puzzle.

Like all ants, carpenter ants have three distinct body segments: the head, thorax, and abdomen (the gaster is the large backend section of the abdomen). What’s notable in carpenter ants is the single, rounded node, or “petiole”, between the thorax and gaster.

This gives them a clearly defined “waist” that’s more pronounced than in termites, which is one reason people use waist shape as a quick identification method. Termites have more of a straight, uniform body, while ants have that narrow middle section.

Carpenter ants have a smooth, evenly rounded thorax when viewed from the side. There are no spines or bumps, and the curve from the front to the back is sleek. This smooth thorax is another key difference from some other large ant species, which might have uneven or ridged thoraxes. And they are large enough that you can see this obvious identifier.

The head of a carpenter ant is proportionately large, especially in major workers. The bigger the ant, the bigger the head—and with that comes powerful mandibles.

These jaws are designed for chewing through wood. But they don’t eat it like termites do, their jaws are built for excavating it to create chambers and tunnels for their colony. They’re strong enough to handle other insects, too, since carpenter ants are omnivores and will hunt when the opportunity arises.

In terms of eye placement, carpenter ants have large, noticeable compound eyes that give them good vision compared to many other ants. This helps them navigate both in the dark tunnels of their nests and in open spaces when foraging.

Carpenter ants have six long, well-developed legs that allow them to move quickly across surfaces. In many species, the legs have a reddish hue, even if the rest of the body is darker. This subtle color contrast can help you distinguish them from other black ants that have uniformly colored legs.

They are skilled climbers with claws strong enough to grip vertical surfaces—don’t be surprised to see them scaling walls, trees, or even hanging from ceilings in search of food.

Like all ants, carpenter ants have elbowed antennae—meaning they bend sharply like an arm at the “elbow.” This is another quick ID point, since termites have straight, beaded antennae instead.

Carpenter ants rely heavily on their antennae for touch and smell. They’re constantly moving and “tasting” the air as they explore, which gives them information about food sources, other ants, and even nearby threats.

Not all carpenter ants have wings, but reproductive males and females called swarmers do. They emerge during the mating season, usually in late spring or early summer, to establish new colonies.

Carpenter ant swarmers are large, with two pairs of wings. The front pair is longer than the back pair, and their wings are translucent with noticeable veins. The presence of wings often leads people to mistake them for termites, but remember the key differences:

• Ants: Elbowed antennae, narrow waist, front wings longer than back wings.
• Termites: Straight antennae, no narrow waist, wings equal in length.

Once mating is complete, females shed their wings and look more like the oversized workers.

The queen is the largest member of the colony. Before she starts a new nest, she has wings like other swarmers. After mating, she sheds them and focuses entirely on egg-laying.

Queens are stockier than workers and have larger thoraxes, a leftover from when wing muscles were attached. In the right conditions, a queen can live up to 20 years—producing thousands of workers over her lifetime!

Sometimes, how an ant behaves is just as telling as how it looks. Carpenter ants are most active at night, and they often travel in single-file lines along walls, tree branches, and utility lines. Sometimes, you can even hear them. If you tap on a wooden beam or wall where they’re nesting, you might hear rustling sounds inside—the movement of workers in their tunnels.

When foraging, they can be seen both indoors and outdoors, often near sources of sweet food or protein. Outdoors, you’ll spot them on trees, logs, fence posts, and if you’re unlucky, maybe even your front porch. When inside, they gravitate toward kitchens, bathrooms, and any area with moisture-damaged wood.

Identifying carpenter ants correctly is critical because they require different treatment than other ants. Misidentifying them as termites could lead to the wrong approach, and assuming they’re harmless sugar ants could give them time to cause serious structural damage.

By noting their size, coloration, body shape, and even behavior, you can confirm whether you’re dealing with carpenter ants—and take action before their tunneling habits compromise your home.

If you’ve noticed a few wood holes and suspect carpenter ants, you can deal with them before they become a more significant issue. Spray a simple vinegar and water solution on these areas to kill and repel these pests. It’s organic and completely safe around humans, pets, and the environment.

However, sometimes a simple home remedy or chemical you buy at your local hardware store is not strong enough to handle your issue. You certainly don’t want to wait until the carpenter ant invasion has caused thousands of dollars’ worth of damage to your home. Call our Kapture professional exterminators who can get rid of the entire colony for you. It will save your home’s structure and a lot of money and frustration in the long run.

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