Undermount vs Countertop bathroom Basins
- Gabrielle Glasson
- Jun 3
- 4 min read

A lot of people ask us during the design process whether they should choose an over-counter or undermount basin for their new bathroom vanity. There's no right or wrong on this choice, but here's a few things to consider to help you make your decision:
look
Undermount basin: It really depends on the look you're going for, but for a more traditional style bathroom such as European or Hamptons, a ceramic undermount basin can look stunning. It creates a more seamless look that draws attention to a beautiful stone countertop and tapware.
A countertop basin is a great way to create a feature in your bathroom, especially when you take the opportunity introduce a new texture, surface material or interesting shape such as with Noodco's gorgeous concrete basins.
Winner - depends on your bathroom aesthetic, but we'll give it to countertop as an opportunity to create a feature.

CLEANING / MAINTENANCE
Undermount basins make it much easier to clean the bench surface and reach around tapware, which is a win in our books, however also keep in mind that the underside of your bench where the sink is attached is also a place where mould can build over time.
An countertop basin creates a space behind the basin that isn't readily visible and can accrue grime, however, particularly if you use wall-mounted tapware and give your bench a frequent wipe down, we find that this needn't be a concern. Grime tends to build up most when you use bench-mounted tapware with water pooling around the connection of the tap.
The material you select for your basin will also play a significant role in maintenance requirements. Check out our blog post on basin materials here to understand what your options are and how they affect maintenance.
Winner: undermount basin

FLEXIBILITY
With an countertop basin, you can turn just about any surface or piece of furniture into a vanity with minimal effort. You can create a one-of-a-kind vanity using antique furniture or a repurposed sideboard.
Given top mount basins only need a small waste hole underneath the vanity they're also readily interchangeable down the track if you decide to go for a different look.
Winner: countertop basin
PRACTICALITY
When it comes to practicality - especially when space is limited - I prefer a countertop basin. When you have tools out like the hairdryer / straightening wand / skincare bits and pieces, a countertop basin lets you use the whole surrounding space without things falling in the sink. It also frees up more storage space in the vanity draws underneath.
Winner: countertop basin

TAPWARE& vanity
If you are going for a top-mounted basin, and especially if you plan to have wall-mount tapware, keep in mind that you'll want your vanity set lower to allow room for your mirror to start at a good height. Make sure your builder knows in advance what type of basin you're using so they can set heights accordingly. Remember that your vanity height should sit at about 850-900mm high including the height of a top mount basin. If you're going undermount, your vanity sits at 900mm. If you're going for a countertop basin though, then your vanity should be set lower at about 750mm to accommodate your basin height.
And while we're on it, your mirror usually starts 50-200mm above your vanity, with the centre about 1500mm-1700mm from the floor.
Keep in mind that not all vanities are suited to undermount basins and this will significantly limit the number of vanity designs available to you.
Winner: planning ahead is what gets the win this time! We'll also give countertop the win for the variety of vanity options to choose from.
PRICE
If sticking to a budget is an important factor in your design then overmount basins tend to be the best bet here. Installation is much simpler when it just needs to rest on top of the vanity rather than be attached underneath.
Winner: countertop basin

INSTALLATION
Caulking is the sealant applied around the basin edge to prevent moisture entering underneath. With top-mounted basins we recommend speaking to your site supervisor to agree on your caulking preferences to avoid surprises. You'll want to weigh up whether you'd prefer a visible line of caulking around the edge of your basin for maximum protection, through to none at all for a more natural look.
Winner: good communication with your builder
SUMMARY
When you are designing your bathroom, you need to consider the basin in context of the whole design: your vanity, tapware and mirror selection all need to work together for comfortable proportions and a cohesive style. Undermount basins are easy to clean and lend themselves to a classic, traditional aesthetic where other elements in the room are the feature, where top mount basins provide a visual feature, flexibility and space efficiency allowing you to maximise surrounding bench space without things falling in the sink. Regardless of your selection, we recommend you speak to your builder early on to ensure your decisions about undermount or top-mounted basins and wall vs counter mounted tapware are factored into your rough in stage so that the heights can be set proportionately.