Supplementing Salt

Your horse needs to consume salt. It’s up to you to make sure that happens.

Let’s start with some salt facts:

Hard work or hot weather will increase your horse’s need for salt.
  • Salt is the only mineral horses will instinctively seek.
  • “Designer” salts, said to be natural or from specific areas, give your horse no more value than inexpensive white table salt.
  • Some natural, unrefined salts can contain toxic minerals.
  • Salt is a chemical called sodium chloride (NaCl).
  • Ensuring a daily consumption of 1 to 2 oz. of salt is necessary to avoid a dehydrated state.
  • Sea salt may not be safe because the oceans are contaminated.


  • 1 to 2 oz. (2 to 4 tablespoons) in cool weather.
  • 2 to 4 oz. (4 to 8 tablespoons) in hot weather.

Horses in hard work may need more and may be advisable for horses with diarrhea or chronic loose manure. Talk with your veterinarian if this describes your horse. Download a PDF of this article.

You should be aware that most horses don’t consume enough salt from a salt block, especially if it’s hot or he’s in hard work. It’s likely that he won’t spend all the time necessary to lick enough salt to meet his needs. He would have to bite off and consume small chunks of salt, which some horses do. 

Yes, most horses do have a natural appetite for salt. Those that seem to avoid free-choice salt may be battling stomach problems (ulcers), mouth irritation, gum disease, or small cuts/scrapes in the mouth.


Salt is the only mineral essentially absent from all hay and grass. However, horses have a natural taste for salt and will seek it out and voluntarily consume in plain form.

Salt controls your horse’s water intake. If the horse’s intake of salt is too low, his body will adjust by holding less water. This keeps the concentration of salt in his body normal, which is good. The bad news is that this leaves the horse somewhat dehydrated.

That’s because, while the salt concentration in the body fluids is normal, the total body fluid itself is below normal. And, because his salt levels are good, he isn’t stimulated to drink more water.

The only way to break this cycle is to make sure a normal amount of salt gets into the horse, as this will change the salt concentration in the body fluids and encourage the horse to consume adequate amounts of water.

Of course, if the horse is healthy and not in hard work, this dehydration state may not cause problems. But, if the horse has further losses of salt and water through sweating or diarrhea, severe dehydration and overheating can occur.

Secondary potassium deficiencies can also occur, causing things like muscular cramps, thumps and poor intestinal motility. These horses are also prone to impaction and other forms of colic from the decreased water consumption.


Despite all the ads for fancy salts, all your horse really needs is plain white salt. You can use bricks or blocks, of course, but realize it may not be enough. He should eat about an ounce of salt a day, and up to twice that in hot weather.

You can, of course, add table salt to his feed, which is what we suggest. Two tablespoons of table salt weighs 1 oz., and there are three teaspoons in a tablespoon.

Most horses will tolerate at least 1 teaspoon of table salt per pound of grain. If more is needed, you can either put it in the bottom of the horse’s feeder before feeding, leave it free choice in a small mineral feeder, or mix it with water and syringe it in after the horse has eaten.

Be careful, though. Horses won’t eat feed that is too salty, and most need to become used to it. Start with ½ teaspoon per pound and work up to an optimal tolerable level we discussed in the beginning of this article.

If your horse has good hydration but rarely even looks at free choice salt, he may be getting salt from other sources, such as your commercial grain or a mineral supplement. Check the labels. If you see salt or sodium chloride listed, go to the guaranteed analysis for more information. A supplement with 10% salt will contain 2.84 grams per ounce, 5% half that, etc. If salt is on the list but not mentioned in the analysis, you’ll have to call the manufacturer to find out how much salt is in there.

If your grain or supplement has salt added, a 1% salt supplement or grain will provide 0.284 grams of salt per ounce, or 4.5 grams per pound.


1 oz. = 28.4 grams

½ oz. = 14.2 grams

1 tablespoon of fine (table) salt = 14.2 grams

1 teaspoon of fine (table) salt = 4.7 grams

Estimated Daily Salt Requirements For Your Horse

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