How to Get Rid of Ants in Your Dishwasher

Ants are one of the most common and irritating pests to find in your home. These tiny creatures find entry points into your house easily, and once they’re in, they can be notoriously hard to eliminate.

Ants spend their lives foraging for food sources to bring back to their nests, so they often wander into strange places. As a professional pest exterminator, I’ve seen it all: ants in the kitchen cabinets, behind appliances, in bowls of pet food, and yes, I’ve even found ants in the dishwasher.

Below, I’ll guide you through how to get rid of ants in your dishwater, in four easy steps. I’ll also provide pointers on how to deal with problem areas, like under the dishwasher, and give tips for dealing with specific species.

Why Ants Love Dishwashers

A dishwasher might seem like a very inhospitable place for an ant. After all, with all that hot water sloshing around, it seems impossible that a tiny insect could survive inside a dishwasher. However, finding ants inside a dishwasher is quite common.

Like all living things, ants need water. Dishwashers provide a place where they can find it. Once the dishwasher finishes its cycle, there is often some water residue on the dishes or inside the machine itself, and ants will go inside to find that water.

Also, dishwashers can have a lot of food remnants in them. The food residue that washes off your dishes doesn’t always make it completely down the drain, and this can attract ants to go inside and find it.

How Do Ants Get into a Dishwasher?

By design, dishwashers seal tightly to keep water in. Ants typically get inside a dishwasher when it’s not fully closed. Maybe you opened the door slightly to let the dishes dry or maybe you didn’t close it between running cycles. Either way, ants only need a tiny little gap to get inside.

If you leave that door open, even just a little bit while the dishwasher is not in use, ants can find a way inside. If you see an ant trail heading towards the dishwasher, it’s because they’ve left a scent trail to follow to this source of food or water.

Getting Rid of Ants in a Dishwasher: 4 Easy Steps

To prevent ants from getting inside your home, or treat areas of your home that have ants, pesticides and other pest control products are often the go-to solution.

However, if the ants are already inside your dishwasher, you’ll need to treat them differently. You can’t spray the inside of your dishwasher with a chemical, after all. Instead, you can address the problem by following these steps:

Step 1. Clean the Dishwasher

First, you need to get rid of what’s attracting the ants. That means getting rid of their food and water sources.

Here are the best practices for cleaning your dishwasher:

Get Rid of Food Remnants

Clean out the dishwasher filter or strainer, making sure there are no food particles inside. Not only will this make your dishwasher less attractive to ants, but it will also help it to run better.

Flush the Drain With Vinegar/Baking Soda or a Commercial Cleaner

Drain flushing breaks up any food particles inside the drain where you can’t reach them. Vinegar and baking soda are a good ecologically friendly way to do this, but there are also products formulated for cleaning the dishwasher drain without being dangerous to your health.

You could also try dumping boiling water down the drain to help flush it out.

Scrub the Dishwasher Thoroughly

There are lots of products on the market that can clean the inside of your dishwasher for you. But if you want to do it yourself, you can sprinkle a quarter cup of borax in the bottom of your dishwasher, then run an empty load.

The borax will break down any food residue and scour the inside of the machine, cleaning it up nicely. As a bonus, borax is poisonous to ants, so if they eat anything contaminated with it they should die.

Check for Leaks, Cracks, and Other Damages

You’ll probably need to remove the dishwasher kickplate to do this effectively. Any moisture beneath the dishwasher might indicate a leak.

The idea is to remove any source of moisture that attracts the ants. Wet wood can also attract carpenter ants, so don’t skip this step.

Step 2. Apply Some Ant Killers

Treating for ants goes a long way to getting them out of your dishwasher once and for good. For heavy ant activity in and around your dishwasher, placing some ant bait stations underneath and around the appliance to kill the colony is your best bet. This is especially true if the ants are nesting inside your home.

On the other hand, if you have relatively light ant activity around the dishwasher, you may be able to deal with it by applying diatomaceous earth or Cimexa dust. These pesticides stay effective as long as they stay dry and are perfect for applying to wall voids such as underneath and behind the dishwasher. For instance, Cimexa stays active for ten years as long as it doesn’t get wet.

Any ants that come into contact with the dust will be killed. This is a great way to kill any foraging ants before they find your dishwasher.

Further, if you prefer natural methods, I highly recommend using essential oils, such as peppermint or tea tree, as ant deterrents. All you have to do is add a few drops (5 to 10, ideally) into a spray bottle with water (or half water and half white vinegar) and apply as you would any other insecticide. A drop of dish soap makes the mixture more deadly.

Step 3. Track Ants Back to Their Point of Entry / Source

Once you’ve cleaned your dishwasher and got rid of the ants inside it, the best long-term solution is to do a little detective work. Look for any ant trails leading to or from your kitchen. If possible, follow the trails to see where the ants are getting into your home.

While some ant species can nest inside a building, most come from outside. Find where the ants are coming in and close the entrance to stop an infestation from ever happening again.

Treat all entry points with an ant-killing pesticide, ideally one that has a residual effect that will either deter or kill any ants that try to cross it. This is your best bet to prevent future ants from getting in.

Step 4. Be Vigilant and Use Preventative Measures

There are many ways to be vigilant against ants. The two most effective practices, in my professional opinion, are:

Keeping the Dishwasher Door Closed

When there are dirty dishes inside the dishwasher, it’s like a feast for ants. A properly sealed dishwasher door makes it impossible for ants to get inside. So keep the door closed tight to keep ants out.

Pre-Rinsing Your Dishes

Before adding dishes to the dishwasher, make sure there are no large food particles. These easily get stuck in the drain or strainer, where they often attract ants. Scrape plates thoroughly and consider rinsing them before they go into the dishwasher to keep as much food as possible out of the machine.

Dealing With Ants Under/Behind a Dishwasher

It’s not always the inside of the dishwasher you have to protect from ants. Sometimes, you may find ants around the appliance.

Ordinarily, ants won’t establish a colony underneath the dishwasher. It’s too close to frequent human traffic, plus it vibrates and radiates too much heat.

Most species like odorous ants or any variety of sugar ants need soil or sand to build their nests. However, certain species of ants can make a home behind the dishwasher.

One of the species is the Pharaoh ant. These tiny reddish-orange bugs can build a nest in just about any void space. They do this by building the nest out of their own saliva, so they don’t need any other medium.

Another ant species that could be nesting behind your dishwasher is the carpenter ant. Carpenter ants get their name from their habit of nesting inside damp wood. They chew holes in the wood to make a nest, and they need enough room for an entire ant colony, so the damage can be extensive.

If your dishwasher has a leak and the wooden floor below it is wet, carpenter ants may see it as a good place to establish a colony. There are a few sure signs of carpenter ants if you’re not sure what you’re up against.

If you do have ants nesting behind your dishwasher, it’s important to understand what kind of ants they are. Carpenter ants and Pharaoh ants look very different, and they behave very differently too and they need to be treated differently.

Treating Pharaoh Ants Around Your Dishwasher

The most important thing to understand is that you should never spray Pharaoh ants with any kind of chemical. This can make the problem worse by causing the ants to panic. The nest will split up into multiple smaller colonies dispersed over a wide area. I also don’t recommend household chemicals like bleach for any ant infestation.

Use Ant Baits (Not Chemicals)

The best way to treat Pharaoh ants is to use bait. These products come in gels, granules, or bait stations. The idea is that the Pharaoh ants take the bait back to the nest and feed it to the Queen and her young without realizing it contains poison.

Baits work slowly, but they are very effective at killing ant colonies you can’t reach yourself. They also don’t cause Pharaoh ants to spread.

Treating Carpenter Ants Around Your Dishwasher

By contrast, spraying is often the best way to deal with carpenter ants. So before you tackle an ant problem behind the dishwasher, make sure you’re certain of what type of ants you’re dealing with.

Apply Spray and Baits Behind the Dishwasher

Some ant baits work on carpenter ants, too. However, spraying is often a quicker and more efficient way to deal with these large ants.

You may need to remove the kickplate at the bottom of the dishwasher to get access to where the ants are nesting or even pull your dishwasher away from the wall.

Apply Powder Under the Dishwasher

Liquid sprays can be helpful, but dust may be a better option. If the area under the dishwasher is dry, dust will stay active for longer and won’t cause any moisture issues.

Use a duster to spread a fine coating of dust underneath the dishwasher, then make sure to put the kickplate back to keep kids and pets away from the treated area.

Black house ants are easy to treat with sprays and dust but typically come in from outside.

Should I Spray Pesticides in My Dishwasher?

No, never spray pesticides inside your dishwasher.

Seeing ants inside your home can easily cause you to panic. The temptation is to try to kill these bothersome insects as quickly as possible. But before you reach for that spray, think about the consequences.

Your dishwasher is where you put your cutlery, plates, and cooking utensils. You don’t want toxic chemicals coming anywhere near those items. Commercially available pesticides are safe to use in the home, but only if you use them correctly.

You should never allow any pesticide to come into contact with dishes or cooking utensils.

Besides, it’s not necessary to spray the inside of your dishwasher. Most dishwashers have a self-cleaning cycle, and you can buy lots of perfectly safe cleaning products or even make your own with vinegar and baking soda.

Ants can’t establish a colony inside the dishwasher itself, only around it. Plus, even if you did spray pesticide inside the dishwasher, it would simply be washed away the next time you ran a load through. So instead of spraying pesticide in the dishwasher, simply clean it using the instructions above and save the pesticide for underneath or behind the appliance.

Can Ants Damage My Dishwasher?

It’s extremely unlikely ants can damage your dishwasher. Dishwashers are mostly made of metal, making them impervious to even the strongest ants.

Ants aren’t interested in wires and pipes. The only reason ants get inside dishwashers is for water or food, not to establish a colony. If you deny them access to food and water, they’ll go elsewhere.

The bottom line? All you really need to do is clean out the dishwasher, perform a pesticide treatment underneath it, set a few baits out, and seal up any gaps or cracks. Then you can clean your dishes again without having to worry about ants.