For a square undermount bathroom sink, match the basin’s outside dimensions to the available vanity and countertop space, then confirm the cutout and drain requirements before buying. The KINGWONG 16-inch model is best for a more generous square basin; CHIKESI suits especially compact spaces; and KDKSC offers a middle-size square option. The DeerValley and Los Flexi sinks are rectangular alternatives for shoppers prioritizing a wider basin.
| Product | Shape and size | Best suited for |
|---|---|---|
| KINGWONG | Square; about 16 inches | A spacious square basin |
| DeerValley | Rectangle; 21 by 15 inches | A wider vanity opening |
| CHIKESI | Square; about 10 inches | Very limited counter space |
| Los Flexi | Rectangle; about 18 by 13 inches | A compact rectangular layout |
| KDKSC | Square; about 14 inches | A medium-size square basin |
KINGWONG 16-Inch Square Ceramic Sink
This sink is best for buyers who want a larger square basin and have a countertop that can accommodate its footprint. The listed exterior dimensions are approximately 16 5/16 by 16 5/16 inches, with a 14-by-14-inch interior. Its undermount installation creates a clean counter edge, while the built-in overflow adds a feature for everyday use.
The ceramic surface is described as scratch-resistant and resistant to dirt accumulation, strong acids, and alkalis. Choose this model if those stated surface characteristics and its square profile suit your bathroom. The 1 3/4-inch drain hole is specified, but the pop-up drain and faucet are not included. Confirm drain fit and countertop cutout dimensions before installation.
DeerValley 21-Inch Rectangular Ceramic Sink
Although it is not square, this DeerValley basin is a relevant alternative for buyers comparing undermount sinks and needing a wider washing area. Its listed size is 21 by 15 inches. The manufacturer describes a glazed white ceramic basin with curved lines and a smooth, low-water-absorption surface. Undermount placement also makes it possible to wipe countertop mess toward the basin.
It is best for a bathroom with enough counter width for a rectangular sink and for shoppers who prefer a more traditional basin shape. The product information describes resistance to scratches, stains, chips, and acid. Avoid choosing it based on square appearance: the listing specifies a rectangle, and the provided features do not give a detailed cutout template. Verify the installation dimensions with the seller before fitting.
CHIKESI Compact 10-Inch Square Sink
This CHIKESI model is best for a powder room, guest bathroom, apartment, or vanity where a standard-size basin would take up too much room. Its exterior dimensions are 10.24 by 10.63 inches, and its interior measures 8.27 by 8.66 inches. The compact square outline suits buyers who want a geometric undermount look with a small footprint.
The sink is made from glazed ceramic, and the listed design includes an overflow. Its surface is described as resistant to scratches, stains, fading, and cracks. Choose it when saving counter space is more important than having a broad wash area. Its small interior is a practical limitation for shoppers who regularly need more room for handwashing or other sink tasks; check the interior measurements against your needs.
Los Flexi Compact 18-Inch Rectangular Sink
This is another non-square alternative, best for buyers with a narrow vanity who prefer a longer basin. Its stated exterior dimensions are 17 15/16 inches long by 13 inches wide by 7 1/16 inches high. The inner bowl measures 15 3/4 by 10 5/8 inches and is 5 11/16 inches deep. A glossy white finish and vitreous china construction are listed.
Choose Los Flexi if a rectangular footprint fits your counter better than a square basin and you want a compact undermount sink. Its smooth glazed surface is intended to simplify routine cleaning. The provided product features do not state whether it has an overflow or provide drain-hole details, so confirm those requirements before purchase and installation.
KDKSC 14-Inch Square Ceramic Sink
KDKSC is best for buyers seeking a square basin between the compact 10-inch option and the larger 16-inch model. Its listed exterior dimensions are 13.8 by 13.8 by 7.3 inches, and its interior is 11.6 by 11.6 by 5.1 inches. The product information notes that actual size may vary by 0.25 inch, so measure the sink and planned opening carefully.
The sink has vertical sides, a glossy white finish, and an overflow. Its high-density glazed ceramic construction and smooth surface are described as durable and easy to clean. Choose it for a simple square profile in a medium-size footprint. The underside is listed as unglazed, which buyers should account for when reviewing the installation details and finished appearance beneath the counter.
Buying Guide: How To Choose A Square Undermount Sink
What size basin fits the vanity?
Measure the available countertop area and cabinet clearance before choosing a sink. Compare the sink’s exterior dimensions with the counter, then check the interior bowl size to judge usable washing space. A compact basin can preserve counter room but may feel restrictive. A larger square sink needs more countertop area and an accurately planned opening.
Should you choose square or rectangular?
A square basin creates a balanced geometric look and may suit a compact or modern vanity. A rectangular sink can provide a longer washing area, but it needs a different countertop layout. The DeerValley and Los Flexi products in this comparison are rectangular, not square, so consider them only if you are open to that shape.
What installation details should you confirm?
Undermount sinks attach below the countertop, so the opening, edge finish, sink depth, and mounting plan need to work together. Do not assume a product’s exterior dimensions are the required cutout dimensions. Confirm the cutout template and installation instructions with the seller or installer. Check whether the faucet, drain, and other required parts are included; the KINGWONG listing explicitly says its pop-up drain and faucet are not included.
Is an overflow important?
An overflow is a feature to compare, not a substitute for monitoring a running faucet. The KINGWONG, CHIKESI, and KDKSC listings specify an overflow. The provided feature details do not confirm one for Los Flexi or DeerValley, so ask before purchasing if it is a requirement.
Frequently Asked Questions
What is an undermount bathroom sink?
An undermount sink is installed beneath the countertop rather than resting above it. This creates a countertop edge that can be wiped toward the basin.
Which listed sink is the smallest square option?
The CHIKESI is the smallest listed square option, with exterior dimensions of 10.24 by 10.63 inches.
Do these sinks include a faucet?
The KINGWONG listing states that a faucet is not included. The supplied details do not confirm faucet inclusion for the other products, so verify each listing before ordering.
Are all five sinks square?
No. KINGWONG, CHIKESI, and KDKSC are square. DeerValley and Los Flexi are rectangular alternatives.
Should the cutout match the sink’s outside dimensions?
Not necessarily. Confirm the manufacturer’s cutout instructions or template instead of using exterior sink dimensions as the countertop opening measurement.