Most bathroom sinks include a small opening near the faucet, and many people are unsure whether this feature serves a real function or if it is simply part of the design. Although it often goes unnoticed, this opening has a clear purpose and is more helpful than it appears at first glance.

This small hole, usually positioned about one-third of the way up the basin, is intentionally built into the sink’s structure. It connects to the drain system and is designed to guide extra water downward. If the faucet is left running while someone briefly steps away, the rising water level can enter this opening before reaching the top of the sink. This provides an additional path for water to exit the basin and helps maintain a safer, more controlled flow.

Over time, everyday use can cause soap residue, moisture, or general buildup to collect in the overflow opening simply because of its location. When this happens, the sink may occasionally develop a light, unpleasant smell. Fortunately, refreshing the area is simple and can be done with basic household items.

If you notice an odor coming from the overflow, you can use a gentle cleaning method to freshen it. A mixture of baking soda and vinegar can be placed into the opening, where it will lightly bubble as it begins to work. Allow it to sit for several minutes, then rinse the sink with warm water to help clear any remaining residue. This easy routine helps keep the overflow opening clean and supports a pleasant, well-maintained bathroom environment.