Real Salt never expires.
Real Salt doesn't expire, because natural salt without additives doesn't ever go bad.
Food only spoils when fungal, bacterial, yeast, or other microbial growth takes place. All of these require water. Salt doesn’t contain water, so it doesn’t support microbial growth, meaning it won’t spoil. In fact, salt is actually used as a preservative for other foods, like meat.
If you’ll notice, we said that natural salt without additives won’t go bad. Refined table salt (the pure white stuff you probably grew up using) will go bad. That's not because of the salt, though. It’s because of the additives. Iodine and anti-caking agents degrade over time, reducing the shelf life of processed salt to about five years.