No, we will not run out of salt. It is one of the most abundant minerals on Earth, and the supply is so large that geologists don’t even bother calculating a finite reserve number. The U.S. Geological Survey describes global continental salt resources as “vast” and the salt dissolved in the oceans as “virtually inexhaustible.” To put a number on it: the world’s oceans contain roughly 50 quintillion kilograms of salt. That’s the number 50 followed by 18 zeros.
How Much Salt Exists on Earth
Salt sits in two enormous reservoirs. The first is the ocean. Seawater averages about 35 grams of salt per kilogram, and there are roughly 1.4 sextillion kilograms of seawater on the planet. That works out to enough dissolved salt to bury every continent under a thick layer of the stuff if you could somehow pull it all out at once.
The second reservoir is underground. Massive deposits of rock salt, called halite, formed over millions of years when ancient seas evaporated. Some of the deposits in the Mediterranean region date back roughly 7 million years, while others in central Turkey formed during a warm period around 14 to 17 million years ago. These deposits can be hundreds of meters thick and stretch across entire basins. Similar formations exist on every inhabited continent.
Current Production Is a Drop in the Bucket
The world produces about 270 million metric tons of salt per year, a figure that has held roughly steady in recent years. That sounds enormous until you compare it to what’s available. The ocean alone contains so much salt that current annual production represents a vanishingly small fraction of the total, something on the order of one part in hundreds of trillions. Underground deposits in the major salt-producing countries are similarly described by the USGS as “large,” with both economic and subeconomic reserves remaining substantial. There is no credible projection from any geological survey suggesting salt exhaustion over any meaningful time horizon.
Where All That Salt Actually Goes
Most people assume salt production is driven by the food on their plates, but table salt and food processing account for only a fraction of global use. The biggest consumers are chemical manufacturers, who use salt as a raw ingredient to produce chlorine, caustic soda, and a wide range of industrial chemicals. Road de-icing in cold climates is another massive draw, consuming millions of tons each winter in the United States and Europe alone. Water treatment, agriculture, and food preservation round out the demand. Even if industrial use grows significantly, the supply picture doesn’t change in any worrying way.
Desalination Could Add Even More Supply
An interesting twist in the salt story comes from the growing desalination industry. As more coastal regions turn to desalination to address freshwater shortages, they produce large volumes of concentrated brine as a byproduct. Dumping that brine back into the ocean creates environmental problems, so researchers are exploring whether it makes sense to extract valuable minerals from it instead.
A 2022 analysis published in Minerals Engineering found that by 2050, the volume of desalination brine produced worldwide could yield extraction potential for certain minerals that far exceeds current global demand. For magnesium, the potential was roughly 2,243 times the 2018 production level. Salt itself, being the most concentrated component of seawater, would be even easier to recover. In other words, the very process of making freshwater could become a secondary source of salt and other minerals, turning water scarcity into a resource opportunity.
The Real Concern Is Environmental, Not Supply
While running out of salt isn’t a realistic worry, the way we extract it does cause real environmental damage. Underground salt mining can destabilize land and alter local water systems. Surface harvesting from salt lakes is particularly disruptive: a study in the Journal of Environmental Health Science and Engineering found that scraping salt from lake beds significantly alters land use, lake topography, and water hydrology. The heavy machinery involved sends salt dust and fuel emissions into the air, and in some locations, naturally occurring arsenic and lead in the salt deposits can become airborne health hazards for nearby communities when truck traffic grinds the surface into fine particles.
Solar evaporation ponds, often considered a gentler approach, carry their own costs. A proposed expansion of evaporation ponds at the Great Salt Lake would have consumed 119 square miles of surface area, threatening the lake’s ecosystem, wildlife, and water quality. A similar project in Namibia raised concerns about habitat loss and dropping water levels in a nearby lagoon. The environmental footprint of salt production is real, even if the supply itself is effectively limitless.
Climate change adds another layer. Rising sea levels and shifting rainfall patterns are pushing saltwater further into river estuaries around the world. Research published in Nature Communications projects that salt intrusion in estuaries will increase by a median of about 9% under high-emission scenarios, with some locations seeing increases above 18%. This doesn’t affect salt supply, but it does threaten freshwater sources and agricultural land in coastal regions. The problem isn’t too little salt. If anything, in many places, it’s too much.
Why Salt Is Essentially Inexhaustible
Salt stands apart from resources like oil, lithium, or rare earth metals because of three features. First, the sheer quantity dwarfs human consumption by many orders of magnitude. Second, it’s geographically widespread, found on every continent and in every ocean, so no single country or region controls the supply. Third, salt doesn’t get “used up” the way fossil fuels do. When salt is used for de-icing roads, it washes into waterways and eventually returns to the ocean. When it’s used in chemical manufacturing, the sodium and chlorine atoms persist in other compounds. The global salt cycle keeps moving regardless of how much we extract.
For practical purposes, salt is one of the few resources where the honest answer to “will we run out?” is simply no. The challenges around salt are about extraction costs, transportation, environmental stewardship, and managing unwanted salt in places like farmland and freshwater supplies. Scarcity isn’t one of them.