Collection: Undermount Bathroom Sinks

Modernize Your Bathroom with a Seamless Undermount Sink

Undermount bathroom sinks are easy to maintain. Since the fixture mounts under the countertop, there’s no rim on top to clean, making daily care a breeze. They go with most vanity and counter styles, making them a flexible option as well. Browse our selection of undermount styles today. 


What is an undermount bathroom sink?

Simply put, an undermount sink is a sink that is mounted underneath your bathroom countertop and attached with clips, epoxy, caulk, and sealants. The edge of your undermount sink is defined by your countertop


Because there is no lip above the countertop into your sink, it prevents moisture, grime, and soap scum from building up around the edges of your sink. Many homeowners love undermount bathroom sinks because they are so easy to clean and feature many timeless colors, materials, and styles. 


Undermount vs. Drop-In Sinks

Drop-in sinks are pretty much the opposite of undermount sinks. Instead of being mounted from underneath the sink, drop-in sinks are installed from above the countertop. They are lowered into a cutout for the sink, with the edge of the sink sitting directly on top of the counter. 


To keep water from seeping between the edge of the sink and counter, caulk is used to seal it. Drop-in sinks are really popular because they are easier to install or replace than undermount sinks. 


However, drop-in sinks do have a lip that catches dirt and grime, which can be more difficult to clean than the smooth edge of an undermount sink.


How to Measure for an Undermount Bathroom Sink

Bathroom undermount sinks come in a variety of shapes and sink sizes, making it important for you to properly measure your sink and countertop before purchase and installation. 


In general, rectangular undermount bathroom sinks are between 12 and 20 inches long and 16 to 24 inches wide. Oval undermount sinks are typically between 12 and 17 inches in diameter. 


Here are some common things to remember when measuring for an undermount sink.


  • If you’re replacing an existing undermount sink, make sure your new sink has the same dimensions. Measure the length (right to left), width (front to back), and depth (top to bottom) of your existing sink. Check that existing plumbing will still work with the new sink.

  • If you are placing a new sink in a new vanity, make sure that the dimensions match up with the hole for your sink and plumbing hook ups.

  • With undermount sinks, you typically need to install a deck-mount faucet directly into your countertop. When measuring, make sure to account for the space your faucet will take up too (check out our guide to bathroom sink faucets for more measuring tips). 

  • Measure available space around your sink, like countertops and space before the walls. Make sure there is some breathing room!

  • Measure the length, width, and depth of your vanity cabinets, making sure to check for sufficient clearance under the counter for the undermount sink–preferably with some room for storage!

  • If you’re installing double sinks in your vanity, make sure that your sink width and counterspace will allow for at least 30 inches between the center of each sink.



Do undermount sinks fall?

If not properly installed, sometimes undermount sinks will begin to sag over time. Worn out clips, inadequate screws, or cheap sealing calk can contribute to this. However, if your sink does begin to sag it can be repaired by a professional sink installer or as a DIY project for experienced DIYers.


Which cabinet materials are best for undermount bathroom sinks?

Because undermount sinks are typically heavier than other sinks, you need a type of countertop that will remain strong and sturdy for years. Solid granite, quartz, marble, or concrete countertops are some of our top choices because they don’t bend or warp.


Can an undermount sink be replaced?

Yes, undermount sinks can be replaced if they crack or break. 


Do undermount sinks add value to my bathroom?

Yes! Undermount bathroom sinks are both a beautiful and practical upgrade many homeowners love to see when shopping for a new home.