Why Does My House Smell Like Onions?

When someone walks into your home, you want them to be greeted by a nice smelling aroma. So when you come back from a trip or really start to smell your home, why does it smell like onions? Since it’s hard for you to recognize your own smell, a weird smell might not be noticeable. No need to worry; we’ve already done the research to bring you the answer!

First and foremost, has someone been cooking with onions? It can take up to two days to get rid of the smell on its own. Here is a list of potential causes:

  • Grime and grease build-up
  • Dishwasher
  • Refrigerator
  • Old carpet or mattress
  • New furniture or carpet
  • Air duct filters
  • Gas leak
  • Carbon monoxide leak

The main spots for an onion smell come from the kitchen but aren’t limited to it. A majority of the time, a deep clean is all you’ll need to fix the smell, but there are cases when something more serious could be playing a role. In this article, we’ll look at how each potential cause arises and how to get rid of the smell. Keep reading to get your house smelling like home!

Stir frying onions in a non stick skillet, Why Does My House Smell Like Onions?

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Grime and grease build-up

You’ve probably had to snake a clogged drain a few times to get all that gross hair out. In the shower, that blockage catches the soap running down in the water along with anything else you’re washing off.

Even with the hair removed, there is still grime and even grease clinging to the sides of the drain. The longer the grease sits, the smellier it gets, and you could get a whiff of that strong onion scent one day.

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Cooking onions in a non-stick skillet

This can also happen in your sink drain. Just think about all the food waste and soap that gets poured down the drain; it’ll end up leaving its mark. Also, keep in mind your garbage disposal; it’s always a good idea to clean that system off every once in a while with the proper cleaning product.

Click here to view this drain cleaner on Amazon.


A secret culprit to smelling like onions. We’ve all been there when we load the washer and then forget to run it. Maybe even forget to run it for a day or two, whoops! If your sink smells okay and the smell is strongest in the kitchen, take a peek inside to see if there are still dirty dishes. Any type of food particulars left over will start to sour and smell.


The vegetable drawer is often overlooked when you’re throwing out leftovers. Maybe you kept half an onion to use for later and then completely forgot about it, and now it’s been in the refrigerator for quite some time. Not only can the onion itself smell, but it can make the other veggies or fruit in the drawer smell like onions too. With not only one thing smelling like onions, but you also have a whole drawer smelling like it!

Tip: Empty the old veggies and let the draw sit in some soapy water to lessen the smell.

Old carpet or mattress

As stated by the Washington Post, there is a phenomenon called “olfactory adaptation where you can’t smell your own scent.” A carpet is constantly being walked on by you, pets, teenagers, and guests. Whether with shoes, socks, or barefoot, the carpet fibers will absorb all those smells. The odor smells a little different to everyone, so the smell that comes with stinky feet may smell like onions to you.

One of the most enjoyable things is cuddling back into your own bed when you come home from a trip. As you bury your face into the bed, you may notice a bit of a stale scent. Mattresses are constantly taking in sweat and body odors when being used. Since you can’t fully wash your mattress, the scent may become noticeable after you’ve been gone a few days. 

Cleaning a carpet using a vacuum cleaner

New furniture or carpet

On the opposite side, new furnishings can bring an onion smell into your home too! The fresh furniture fibers, such as a couch or even bedsheets, can hold onto the plastic wrap smell. Due to the fact, it’s industrial plastic it’s not going to have the same scentless nature as the saran wrap. It’ll have a strong smell for a few days but will disappear once you start using them.

Air duct filters

Your AC system functions to circulate air around your house. That’s why when you’re cooking with onion or garlic, it often draws people out of their rooms to see what’s cooking. When the air is traveling through the ducts, they’ll have filters to pass through. However, out of sight, out of mind, the filters are often changed out well past their due date.

The filters help catch dander, dust, and smell from passing through the central HVAC itself. This means that if the air filter is dirty and isn’t filter out what it needs to be, smells can get trapped. That leads to the oniony smell sitting and blowing through the ducts when the AC turns on.

Tip from the Service Experts of HVAC and Plumbing: It’s best to change your air filters every 30-60 days.

Click here to view these air filters on Amazon.

Can a gas leak smell like onions?

Gas usually smells like rotten eggs due to the sulfur content in its makeup. However, because some people smell things differently, it is possible for a gas leak to smell like onions or chives. If you have none of the problems above, start looking at where your pipes are inside the house. If you hear a hissing or see dust blowing where it shouldn’t be, it could be a gas leak.

Even pipes from old appliances that aren’t used as much can develop small leaks over time. You may also notice your whole family or roommates experience flu-like symptoms and headaches. If this is the case, ConEdison Gas company recommends exiting the home immediately and call the city for help.

Do not try to turn anything on or off, and don’t even use the phone while inside. Any type of electric heat could cause a spark in the gas. 

Tip: In an older home, you’ll benefit from installing a gas detector for extra safety. 

Click here to view this natural gas detector on Amazon.

Does carbon monoxide smell like onions?

Carbon monoxide does not smell like anything, which makes it harder to identify. You’ll find carbon monoxide coming from fumes in fireplaces, gas stoves, water heaters, car engines, generators, and furnaces when the natural gas doesn’t burn completely. Carbon monoxide can be very dangerous to both humans and animals.

Since there is no smell to tell you something is off, have a monoxide detector installed. A leak of carbon monoxide will also induce flu-like systems with intense headaches and muscle weakness. The visual sign of a leak is a brown-ish yellow stain around the leaking appliance.

Does mold smell like onions?

The typical smell given off by mold is a musty and earthy scent. In some instances, it could also smell like rotting veggies and plants, which means it can smell like onions. The onion odor from mold is found more often in humid areas, such as the shower. Water will stick to the walls and ceilings when there isn’t strong enough ventilation.

An older homeowner, Eliza Meeks, talks about her struggle getting rid of the onion smell in her bathroom by first changing out the shower curtain liner, but you could also require recaulking and scrubbing the ceiling with mold killer. Since it does smell different to everyone, take time to look around moist areas of your home to see if there are any mold spores or discolorment.

Click here to view this curtain liner on Amazon.

How do you get rid of the onion smell in a house?

The number one way to fix an onion smell in the home, baking soda. Baking soda has a natural neutralizing property and can easily handle that pesky onion smell. Add a box of baking soda into your fridge to help keep the entire fridge neutral. You can also sprinkle some baking soda into the trash can if you can’t take it out yet, but it has a faint odor to it.

If you’d like to also have a fresh smell with it, put a bowl of baking soda and lemon rinds into the fridge. You can also use it to begin cleaning surfaces, including cutting boards, fridge drawers, and countertops. While these areas are being soaked, boil some cinnamon sticks for a comforting aroma in the house.

Trick: A deep steam clean could be in order for larger items, such as the carpet. A mattress may seem hard to clean, but in fact, you can also sprinkle some baking soda on it and vacuum it off!

Baking soda inside the fridge

In Closing

Your home may smell like onions all the way from cooking to needing a deep clean or bacteria build-up! There are plenty of solutions to make your home smell more pleasant and welcoming. Don’t be surprised if you start getting more guests after boiling some cinnamon sticks! Before you go, be sure to check out these other guides:

Is Carpet Deodorizer Safe For Pets? (These 5 Are!)

Why Does My Bathroom Sink Smell? [And What To Do About It]

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