Licensed Plumber LICENSE #CO88900054
Call For a Licensed Plumber: (317) 859-9999

Most homeowners try pretty hard to keep revolting odors out of their bathroom. They clean their toilet regularly. They empty the wastebasket. They keep the bathroom stocked with potpourri or deodorizing spray.

But what if those efforts aren’t enough to keep your bathroom from stinking? What if the nasty smell is not coming from the toilet or the trash, but from the sink?

If you have a foul smell coming from your bathroom sink, there may be a number of possible reasons for it. Some of these issues may be easy, DIY fixes, while others may require you to hire a professional plumber. If you live in the area visit our drain cleaning Indianapolis service page.

Watch this video to learn more about how to fix bathroom sink smells

In this post, we’ll share some tips for troubleshooting your sink odor. And, we’ll recommend some methods for keeping your bathroom smelling fresh and clean.

Bathroom Sink Smell

What Causes the Smell Coming from Your Bathroom Sink?

Generally speaking, if there is a revolting odor coming from your sink, it is for one of three reasons:

  1. There is a build-up of bacteria in your sink.
  2. There is an issue with your ventilation.
  3. There is no water in the p trap.

Let’s take a look at these issues one by one.

There’s a Build-Up of Bacteria in Your Sink

Just think about all the stuff that you put into your sink, day after day. Toothpaste. Shaving cream. Soapy water. Dead skin cells. All of these materials find their way into the drain, where they are flushed down into warm, dark pipes. It just so happens that these pipes provide the perfect environment in which bacteria can grow and flourish. Over time, this buildup of bacteria may result in nasty, black gunk, called biofilm. And that biofilm can sometimes emanate a fairly unpleasant smell.

So how can you tell if the problem you’re dealing with is from biofilm in your sink drain? There’s actually a very simple way to diagnose this issue. Simply disconnect the stopper, pull it out, and see if the underside of it is covered in black film. If it is, then that means your pipes are, as well.

The good news is that the smell caused by biofilm is pretty easy to eliminate; more on that later in the post.

There’s a Problem with the Sewer Line

Does the odor you’re noticing seem an awful lot like a sewage smell? Well, that may be because it is. The sewer smell could point to a deeper problem with your plumbing system, including sewer gas rising up through your drain.

Bear in mind that all the waste you send down your pipes ultimately goes to the same place; in other words, there’s somewhere down the line where your bathroom sink links up with the line coming from the toilet.

If you believe you’re getting a whiff of sewer smell from any of your bathroom drains, it may be due to an issue with the vent or with the p-trap.

A Problem with Your Vent

Plumbing systems come equipped with vents, which let that nasty sewer gas escape rather than getting trapped in your home. If you’re smelling sewer gases through your drain, that might mean the ventilation system is clogged in some way.

A Dry P-Trap

The alternative is that there is a problem with the p-trap. This is the U-shaped segment of pipe you see under the sink. The role of this p-trap is to hold a protective barrier of water, which keeps sewer gases from wafting up through the pipes and into your bathroom. If the p-trap goes dry, however, then you no longer have that barrier to keep sewer gases from drifting up into your home. Not only can this be extremely unpleasant, but it can actually be highly unsanitary, as well.

This is most likely to happen in a guest bathroom, or in any bathroom that doesn’t see as much use. Over time, the p-trap may simply go dry. This is an extremely easy fix; more on that shortly!

Clean Bathroom Smell

How to Remove the Nasty Smell in Your Bathroom

Now that we’ve identified some of the most common causes of foul odors in your bathroom sink, let’s get into some potential solutions. There are a number of ways to address the problems we’ve listed so far, as well as some more general strategies to keep your bathroom sink smelling fresh and clean.

Clean Your Sink to Remove Biofilm Buildup

We mentioned earlier that one possible cause of a smelly drain is biofilm buildup. Again, this is a pretty easy thing to check for; just detach your stopper, pull it out, and see if there’s nasty black gunk on the bottom of it.

If so, that means all you really need to do is thoroughly clean out your sink, including a deep-clean down through the drain and into the pipes. You need to eliminate that bacterial buildup, which is what’s causing the foul odor.

So what cleaning supplies should you use to clean out your biofilm buildup? You can invest in any store-bought cleaning product that’s specifically designed to clean sinks. You can also just use vinegar (preferably white, distilled vinegar). One important word of caution: Never mix vinegar with bleach. Doing so can produce noxious, potentially dangerous fumes.

Once you’ve used the cleaner of your choice, we recommend either pouring a couple of cups of hot water down the drain or simply allowing the hot water to run for about a minute. This can further break down and flush away bacteria.

If your bacteria buildup is really extreme, this method of cleaning may not be sufficient. In this situation, you may want to turn off the water source, take apart the plumbing under your sink, and clean out each pipe individually. You can usually do this easily enough by using a paper towel inside each pipe. You can also rinse them out with an outdoor faucet or hose. Of course, you’ll then need to reassemble the plumbing, which should be pretty self-explanatory, but you can always call a plumber if you get stuck!

Add Water to Your P Trap

What course of action is best if the cause of your sewer smell is a dry p trap? This may be an even easier fix. Often, all you’ll really need to do is run water for a few minutes, allowing that p trap to regain its protective moisture barrier. If this doesn’t work, then it’s possible that you’ve misdiagnosed the problem; or, that you’ve reached the point where you need to call a plumber.

Fix Your Ventilation

The third issue we discussed was a faulty ventilation system, allowing sewer gases to get trapped in your home and waft up through the drain. This is a more complex problem and may require some deeper repairs to your home plumbing system. In this situation, you’re probably better off calling a plumber to help tackle your unsavory bathroom smells.

Addressing Other Problems with Your Sink

We’ve hit on the primary reasons why a drain smells… but what happens if we haven’t covered your problem? Allow us to provide a few additional strategies for diagnosing and removing a bad bathroom smell.

Check the Overflow Pipe

Do you see a small hole, located toward the top of your sink? This is what’s known as the overflow. It’s there to keep your sink from overflowing; if the water level gets too high, it will drain through that hole, rather than spilling out onto your floor. The overflow is actually a magnet for soap scum and other forms of buildup, and over time, you may get some unsatisfactory smells coming out of this little hole. You can clean this out by pouring vinegar or even a household bleach down the hole. You might also buy a small toothbrush, or some other kind of brush, to scrub out the inner rim of the overflow hole.

Address Buildup in Your Pipes

We already mentioned the possibility of biofilm accumulating in your pipes. Well, it’s also possible that you could have hairballs, grease, and other undesirable stuff accruing in there, causing smells to waft up through your drain. In addition to vinegar and boiling water, another way to clean out the sink drain (and remove foul smells) is to use a combination of baking soda and vinegar. This mixture produces a combustible effect that can dislodge the build-up and unclog your drain… which may, in turn, remove the smell. (Again, make sure you never combine vinegar with bleach; don’t try the baking soda and vinegar trick if you’ve just used a high-powered cleaner.)

Clean the Basin of the Sink

Don’t overlook the possibility that you’re noticing a foul smell because there’s funk built up in the basin of your sink, not deeper down in the drains. While this is most common in the kitchen sink or garbage disposal, where food particles can build up over time, it may sometimes happen elsewhere in the home. A simple cleaning can restore your sink to its normal level of sanitation (and, to a more pleasant aroma). Close the drain, add some soap, and fill the basin with hot water (you can even use boiling water if you like). Let it sit for a few minutes, then let the water out as you give the basin a good, thorough scrubbing. See if this helps you eliminate that unwanted scent.

Keep Your Bathroom Smelling Fresh

Clearly, there are a number of ways in which your drains can acquire an unpleasant scent; and, thankfully, most of these issues are fairly easily remedied. Again, if you have any problem with your drains that you just can’t fix, we invite you to contact a professional plumber for back-up.

In the meantime, there are a number of simple strategies you can keep to make sure your powder room maintains a pleasant, welcoming aroma at all times. We hope you’ll find these quick tips and habits to be useful.

  • Invest in some scented trash bags. You can find these at pretty much any big box store, or just order them from a place like Amazon. Use them to line your wastebasket, and they will emit a pleasant aroma to offset any foulness within the garbage itself.
  • Wipe down the sink on a regular basis. Develop the habit of using a Clorox wipe to scrub down the entire vanity/surface area at least a couple of times a week, if not every day. The best way to keep smells from accumulating is to keep dirt and grime from gathering.
  • Wipe down the shower curtain or door. If you notice an odd smell coming from the shower, it could be the shower drains… but then again, it could just as easily be mold or mildew growing on the inside of your curtain or door. You can avoid this by making sure you give these areas a quick scrubbing any time you use the shower.
  • Hang up your towels and bath mats properly. If you wad up wet towels and leave them in the corner, they are likely to gather mildew. Ultimately, they will start to stink. Make sure you hang them properly to avoid this; and, toss them into the laundry at the first foul whiff.
  • Use scented candles from time to time. While you don’t necessarily need a candle burning around the clock, it can occasionally be an effective way to purge the room of any undesirable smells. Proper ventilation, including open windows, can also go a long way.

These are just a few easy, practical ways to ensure your restroom area remains as clean, as hygienic, and as welcoming as possible.

Plumber Indianapolis

Plumber Indianapolis

More Questions? Call a Plumber

We hope you’ve found these guidelines to be helpful as you troubleshoot and eliminate unwanted smells, whether they’re coming from your drains or elsewhere.

If you are looking for Plumbers in Indianapolis and come across a problem that’s a little beyond your expertise, don’t hesitate to call Carter’s My Plumber. We’d be happy to take a look at the issue and to help you get your home smelling fresh and clean again. Contact us at any time.

Kelson Carter

Article reviewed by:

Kelson Carter, aka, The Prince of Plumbing

Kelson is a 3rd generation Plumbing Contractor. His family business is located in Greenwood, Indiana, and provides Residential Plumbing Service to the Indianapolis Metro market.

Kelson grew up watching his grandfather and father do plumbing. After graduating high school, Kelson went to Trade School and became a Licensed Master Plumber and Licensed Plumbing Contractor. He is also Certified in Backflow Prevention. He currently owns and operates Carter's My Plumber with his parents.


Schedule Your Appointment Now

  • MM slash DD slash YYYY

Thanks, Jacob! Get a company you won't hesitate to book a call with in the future! See you in 2025/2026, Nick! ⭐⭐⭐⭐⭐
Glasses on & ready to conquer this day. Where are you watching at?
Plumbing or problem solving? Same thing! 

Happy Hump Day! Call Carters to get your problems solved. 
Happy 1 Year Work Anniversary to one of our apprentice plumbers, Wes! This guy is hardworking, always looking for opportunities to learn, and makes sure our customers are truly provided with outstanding customer service! We're lucky to have him on TEAM CARTER! 

If Wes is in your home this week, give him a big CONGRATS! He deserves it! 🛠💪💦
Were you up last night & immediately starting to wonder if your sump pump was doing the job? Even worse, did you wake up to a flooded basement? 

Skip the headache & the lack of sleep- schedule a sump pump stress test TODAY. Visit us online at to see our available coupons! Don't wake up UNDER WATER 💦
Happy smiles & 2 thumbs up for these Carter Plumbers! 

Way to go, Gabe! ⭐⭐⭐⭐⭐

Kind & considerate- perfectly describes this guy!
Dispatch or expert, car washing machine? 

HAPPY MONDAY! Get a squeaky clean Carter truck in your drive this week, call us at 317-859-9999 💪
What he said! Happy Friday! Make the day a good one, call US! 

And so it begins....

Who you taking to the top?
Have you seen Joe? 

A little dirt won't hurt. 💪
Happy 2 Year Work Anniversary to one of our apprentice plumbers, Jacob! This guy is eager to exceed, quick to hop on an opportunity to learn, willing to take on new challenges, and a true joy to have on our team! We're pumped he's a part of our team and can't wait to see his growth in the year to come! 

If Jacob's in your home this week, give him a big congrats! He deserves a big pat on the back! 💦💪👑
Way to go, Joe! A heck of a review from a customer who has made Carter's THEIR plumber! ⭐⭐⭐⭐⭐