Question & answer

Can an Undermount Sink Be Used as a Drop-In?

Only if the maker says so. Dual-mount sinks are built to go either way, such as the Kohler Task. A sink sold only as an undermount isn't meant to sit on top, and the maker's mounting clips and template assume it goes below.

by the editorial teamupdated November 3, 20262 min read

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The short answer

Only if the sink is sold as dual mount. Family Handyman says dual-mount sinks can be installed either way, though a drop-in use still needs separate faucet holes. The Kohler Task is one, with top-mount or undermount options. Sinks sold only as undermounts, such as the KRAUS KHU100-32, come with hardware for below the counter, so buy a real drop-in instead.

On this page

The word to look for on the listing is dual mount, or both top mount and undermount named by the maker.

What the sources say

Family Handyman says dual-mount sinks can go either way, but that drop-in use still needs separate faucet holes planned. It also says switching between the two styles during a renovation is uncommon, since the counter prep differs.

Kohler's sheet for the Kohler Task 33^* names both mounting types, and that's the one on our list.

Why not just set an undermount on top?

A sink made only for undermount comes with what it needs for that job: KRAUS lists a cut-out template and mounting hardware for the KHU100-32. We read nothing from a maker that supports using such a sink from above. It would also be outside what the sheet covers, which can matter for the warranty. So we'd say no.

How to tell from the listing

Look for the mounting type in the specs. A maker that means both will name both, the way Kohler does with top mount and undermount on the Task's sheet. If only undermount is named, treat it as undermount only. A rim that looks wide enough in a photo isn't enough to go on.

Then look at the faucet holes. A sink that sits on top usually has its faucet on the deck, and Family Handyman says drop-in use still needs those holes planned. The Kohler has one on its sheet. If your faucet needs more than that, it won't suit this kind of use, even if the mounting does.

Last, check what the warranty says about mounting. If you're not sure, ask the maker in writing before you cut anything.

What to do instead

Laminate counter? See undermounts in laminate and the drop-in guide.
Might change the counter later? Take a dual-mount sink. Kohler has the details on the Task.
Still deciding? See undermount or drop-in.

Asked before buying

Can a drop-in sink be used as an undermount?

Not unless the maker says so. Family Handyman says converting between the two during a renovation is uncommon, because the counter is prepared differently. The rim of a drop-in is made to sit on top, and an undermount calls for a precise opening with a finished cut edge.

Where does the faucet go on a dual-mount sink?

It depends how it's mounted. Used as an undermount, the faucet usually goes in the counter. Used on top, it needs holes in the sink deck, and Family Handyman says these need planning. The Kohler Task K-80084-1PC has one faucet hole on its sheet.