Baking soda is a staple in most kitchens, praised for its ability to deodorize refrigerators, leaven baked goods, and—most famously—clean drains. When paired with vinegar, it’s often touted as a natural, chemical-free alternative to harsh drain cleaners.

Here’s the short answer: However, when used incorrectly or in combination with other substances, it can absolutely contribute to a blockage.

Let’s separate the science from the myths. Pure baking soda (sodium bicarbonate) is water-soluble. When you flush it down the drain with plenty of hot water, it dissolves and washes away completely. It will not stick to pipes, harden, or create a blockage on its own.