Why Drivers Are Storing Salt in Glass Jars Inside Their Cars—And How This Simple Hack Can Make Winter Driving Easier

Introduction

Every winter, seasoned drivers quietly prepare their cars with a handful of clever tricks—one of the most surprising being a glass jar filled with ordinary table salt. While it might look strange at first glance, this simple DIY solution can save you time, protect your vehicle, and make cold-weather commuting much safer. The salt-in-a-jar hack works by combating moisture, preventing frost buildup, and improving visibility on icy mornings. Here’s everything you need to know about using this method effectively.

Ingredients (What You Need):

1 clean glass jar with a lid (mason jar works best)

½ to 1 cup table salt (rock salt or sea salt also works)

A piece of breathable cloth or coffee filter

A rubber band or the jar ring to secure the cloth

Optional: A few drops of essential oil for scent

Instructions:

Prepare the jar:
Remove the metal lid insert, leaving the jar ring or band. Replace the lid insert with a breathable cloth or coffee filter. This lets air flow through while keeping salt contained.

Add the salt:
Pour salt into the jar, filling it halfway. Salt is naturally hygroscopic—meaning it absorbs moisture from the air.

Secure the cloth:
Place the cloth over the opening and tighten it with the jar ring or a rubber band.

Place the jar in your car:
Set the jar on your dashboard, under a seat, or in a cup holder. As the salt absorbs moisture inside the vehicle, it helps reduce fogging and limits frost formation on the inside of the windows.

Check and refresh:
After a few weeks, shake the salt to break up clumps. Replace it every 1–2 months during colder seasons.

Serving and Storage Tips (How to Use and Keep It Working):

Use multiple jars in larger vehicles for better moisture control.

Avoid sealing the lid completely—the salt won’t work unless air can reach it.

Store extra salt in a dry place for easy refills throughout the winter.

Place the jar in a stable spot, ensuring it won’t tip over while driving.

If the salt becomes damp and clumpy, it’s done absorbing and needs replacing.

Variations: