Start by recognizing that the tiny hole near your faucet isn’t just decorative — it plays an important role in how your sink functions. Known as the overflow opening, it’s positioned about a third of the way up the basin and connects directly to the drain system. Its main purpose is to redirect rising water if the faucet is left running, helping prevent spills and protecting surrounding countertops and flooring.

Next, understand how it works in everyday use. If the water level begins to climb, the overflow provides a secondary route for drainage, easing pressure on the main drain and slowing the rise of water in the basin. It’s a built-in safety feature that offers peace of mind, especially during busy moments or distractions.

Then, pay attention to maintenance. Because the opening doesn’t receive the same regular rinsing as the rest of the sink, soap, toothpaste, and moisture can gradually collect inside. That buildup may lead to mild odors over time — a common and easily fixable issue. Inspect the overflow occasionally so you can address any residue early.

Finally, clean it with gentle household products. Sprinkle a bit of baking soda into the opening, follow with a small amount of vinegar, and let the mixture fizz for several minutes. Afterward, run warm water through the sink to flush out loosened debris. This quick routine keeps the overflow fresh, supports proper drainage, and helps maintain a pleasant bathroom environment with minimal effort.