That small opening near the top of a bathroom sink is often overlooked. While many assume it is simply part of the design, it is actually a functional feature called the overflow hole.

This opening serves an important purpose in preventing household accidents. It connects directly to the sink’s drainpipe, providing a secondary pathway for water.

If the main drain is clogged or the faucet is left running, water will flow into this hole before it can overflow the basin’s rim. This helps avoid water damage to your countertop and floor.

It is a simple but effective safety mechanism for busy or distracted moments. However, its position inside the basin makes it prone to collecting soap scum and residue.

When neglected, this buildup can lead to unpleasant odors or a visible dark film. Regular cleaning is needed to keep it functioning properly.

Maintenance is straightforward using common household items. A small amount of baking soda poured into the opening, followed by warm water or a vinegar rinse, will dissolve most blockages and neutralize odors.

With this occasional care, the overflow hole can continue its quiet role. It remains a vital part of maintaining a safer and more efficient bathroom.