Undermount kitchen sinks are installed beneath the counter. They are held up by brackets, clips, and adhesive. Because the whole sink will be hanging from underneath the counter you have to ensure that the sink is installed properly to support its weight. This includes choosing a material for the countertop that will have enough strength to support the sink.
Undermount sinks will not hold up well with laminate or tile countertops. They are intended for installation with solid countertop materials – granite, quartz, stone, marble, concrete. Also, undermount sinks typically do not have pre-drilled holes for faucets or soap dispensers, so they would have to be added to the countertop.
While they can be more work to install, undermount sinks allow you to maintain a smooth countertop and easily sweep debris into the sink.
Kraus KHU100-32 (32”, 16 Gauge Stainless Steel, Single Bowl)
A simple, functional, and heavy-duty single bowl undermount sink is the Kraus KHU100-32. As a stainless steel sink, it will match all kinds of kitchen décor. It is made out of 16 gauge stainless steel which is 1.5 mm thick – the best thickness for a quality kitchen sink. A good quality kitchen sink is at least 1.2 mm thick, or 18 gauge.
The 32” size is pretty much standard for a kitchen sink. Its exact dimensions are 32” by 19” by 10”. To compare, a standard kitchen sink is 33” by 22”, and between 8” to 10” deep. Undermount sinks are a couple of inches short from front to back to accommodate space for installing the faucet and soap dispensers.
At 10” deep this sink tries to give you as much space to work with as possible. It has a deep, large bowl. You will need a minimum cabinet size of 36” to install this sink. Overall, it is a durable, easy-to-clean, beautiful, and functional undermount sink.
Kraus KHU102-33 and KHU103-33/KHU104-33 (33”, 16 Gauge Stainless Steel, Double Bowl)
If you like the Kraus KHU100-32 but want two bowls instead, then get the KHU102-33 or KHU103-33/KHU104-33.
The KHU102-33 features two equally-sized bowls, while the KHU103-33 features a larger and smaller bowl (60 left/40 right) and the Kraus KHU104-33 features a smaller and larger bowl (40 left/60 right).
They are about an inch larger than the single bowl sink to accommodate the divider, but all of these sinks will install on a minimum cabinet size of 36”.
Kohler Prolific K-5540 (33”, 18 Gauge Stainless Steel, Single Bowl)
The Kohler K-5540 undermount sink is probably the coolest sink you can find. Rather than a sink, it is a workstation. It has three graduated ledges where you can place a cutting board, washbin, colander, and multipurpose rack where you can do all your cutting, washing, drying right inside the sink. This saves counter space and you don’t have to move around or get the counters messy and wet. When you buy the sink it comes with all the accessories: bamboo cutting board, two multipurpose grated racks, colander, and washbin.
As a complete workstation, it has a sloping drain designed to work well with feeding your garbage disposal. It has an actual workspace depth of 10 inches so you have plenty of room to work with. As an undermount sink it has no holes for the faucet or soap dispenser so you have to install them in your countertop. It requires a minimum 36” cabinet space to install. This sink is ready to work and would appeal especially to those who have small kitchens because it saves counter space.
Kraus KGU-413B (31”, Composite, Single Bowl)
The Kraus KGU-413B is a beautiful undermount composite sink. It is made out of 80 percent granite that looks and feels like real stone. The quality is superb and it feels like a steal given its low price tag. There aren’t a lot of composite undermount options on the market that match this sink in terms of quality and price.
With dimensions at 31” by 17” by 9”, it can feel a bit smaller than the standard kitchen sink. However it can fit a minimum cabinet space of 33 inches. And given its single bowl configuration it provides a large enough space to work with. It is only available in Black Onyx – a beautiful color that is likely to match any kitchen, but may or may not be what you’re looking for. The quality, price, and simplicity are what make this sink special.
Blanco Diamond (33”, Composite, Double Bowl)
The Blanco Diamond that was on our list for the best drop-in kitchen sinks also comes in an undermount version. The double bowl undermount sinks have both equal and offset bowl configurations. Just like the drop-in versions they come in a variety of colors.
The dimensions are roughly 32”/33” by 19” to 22” by 9.5”.
A Word About Installing Undermount Kitchen Sinks…
When installing an undermount sink, you can position the sink so that the rim is either flush with the countertop edge, has a positive reveal (the edge of the rim sticks out), or has a negative reveal (the edge of the rim is hidden). The differences are mostly aesthetic.
But in the case of installing an undermount sink with a positive reveal, you can use the rim to hold a cutting board that you can use directly on top of the sink. And from there you can easily sweep food scrap into the sink and into the garbage disposal.
Because undermount sinks can be tricky to install, we recommend hiring a professional.