The Best Ways to Repair a Cracked Sink

It happens: You’re washing your hands or the dishes and you notice a crack in your sink. It’s tiny, and a quick check assures you that your sink isn’t leaking—but it is the nature of cracks to get worse over time, and even if a hairline crack in your sink isn’t particularly noticeable, they can blacken and discolor over time, or (depending on the type of sink you have) cause the underlying metal to rust.

Sinks crack for one of three reasons: You dropped something heavy on it; you have an over-tightened drain connection or garbage disposal; or you inflicted what’s known as “thermal shock” on your poor, suffering sink either by running extremely hot water into it or switching suddenly from cold to very hot water. Porcelain and other materials commonly used in sinks react to those temperature swings by contracting and expanding, and if that happens too fast you get a crack.

The good news is that if your sink isn’t leaking you can repair the sink instead of replacing it. If you take your time and work carefully, the repair can be almost unnoticeable.

While the basic process of fixing a crack in your sink is more or less the same, you need to match the repair material with your sink. The most common choices—aside from solid metal like stainless steel or copper—are:

Once you know what you’re trying to repair, you can proceed with the repair.

The best way to repair a cracked sink is to fill in the crack with a waterproof bonding material, then sand and paint the repair to match the rest of the sink. Done properly, this will not only hide the imperfection, it will prevent moisture from causing damage to the sink. First, buy some repair material:

While you should follow the specific instructions that come with each of these products, they all follow the same basic steps:

Once the paint dries, your repair is done and (hopefully) unnoticeable.

If your crack is pretty thin and small, you might be able to repair it using silicone caulk. This is a lot easier, a lot faster, and a lot cheaper, but won’t produce the best aesthetic results—unless you’re very, very careful and a little lucky. Caulk will work best on tiny cracks at the seam of your sink (i.e. where the vertical and horizontal planes meet).

First, isolate the crack with some painter’s tape. Get as close as you can, minimizing the amount of sink surface affected. Try to color-match your sink if possible; a white porcelain sink might match up well with a white caulk, but chances are a perfect match will be difficult. Using the narrowest possible bead, apply your caulk, carefully smooth it into the crack, then remove the tape and let it dry. This will at least hide the crack and stop moisture from infiltrating, and with a little luck won’t look too bad.

A tiny crack in your sink isn’t a huge problem. With just a few hours of your time and a small amount of money, you can repair it before it becomes one.