18 Inch Undermount Bathroom Sink Small Rectangle Undermount Sink

In this review of the 18 inch undermount bathroom sink, the bottom line is simple: it is a compact, well finished option for small vanities that need a neat, rectangular basin. The sink is aimed at homeowners or renovators who want a durable white under counter sink with a clean vertical-sided profile and overflow but without faucet holes, and the single biggest reason to choose it is the combination of accurate small dimensions and a glazed vitreous china finish that resists staining and cleans easily.

Key Features

• Compact 18 in size: The external 18.3 in by 13.8 in footprint fits tight vanities while providing usable internal bowl space for everyday use.
• Undermount design: The under counter installation gives a seamless edge to the countertop and simplifies cleaning around the rim.
• Glazed vitreous china: A high density, high quality glaze offers long lasting durability and a smooth, nonabsorbent surface that wipes clean with minimal effort.
• Rectangular shape with vertical sides: The straight-sided silhouette maximizes usable interior volume and suits modern or transitional vanity styles.
• Overflow included: The built-in overflow adds a practical safety margin against accidental overfilling without changing the clean top surface.

Who It's For

This sink is best for people renovating small bathrooms, powder rooms, or tight vanities where counter space is limited but a functional basin is required. It is a good fit for DIY installers who plan an undermount installation and have compatible hardware and a countertop cutout sized for an 18.3 in by 13.8 in external dimension.

Those who need integrated faucet holes, a decorative top-mount sink, or a larger, deeper basin for heavy-duty use should look elsewhere. Also check hardware compatibility before purchase, since some customers reported mixed results matching templates and mounting components.

Pros & Cons

Pros

• Compact footprint fits small vanities without looking cramped.
• Durable glazed vitreous china finish resists stains and is easy to clean.
• Rectangular, vertical-sided design maximizes usable interior space and modern appearance.
• Includes overflow for added protection against spills.

Cons

• Pop-up drain and faucet are not included, so additional purchases are required for a complete installation.
• Hardware compatibility can be mixed; verify mounting and drain fittings before installation.

Specifications

Our Verdict

The 18 inch undermount bathroom sink is a solid value for small-vanity projects where a clean, rectangular under counter basin is desired. Its durable glazed vitreous china finish, correct small dimensions, and built-in overflow make it practical and attractive for renovations, though buyers should plan to purchase a compatible drain and faucet separately and confirm hardware compatibility.

Frequently Asked Questions

Does this sink include the drain and faucet?
No, the package contains the sink with overflow only; pop-up drain and faucet are not included.

Is this sink suitable for undermount installation on a stone countertop?
Yes, it is designed for under counter installation, but verify the countertop cutout and mounting hardware compatibility before installation.

What are the internal bowl dimensions?
The internal bowl measures approximately 16.1 in by 11.6 in with a depth of 4.9 in.