Salt Block or Loose Salt for Horses? What a New Study Found

Salt block vs loose salt for horses: the short answer

A new study says it barely matters. Horses ate about the same amount of salt, and drank about the same amount of water, whether they were offered a white salt block or loose salt. What mattered was the individual horse.

The work comes from Colorado State University. A summary by a University of Minnesota researcher ran in Equine Chronicle on 6 October 2026, and the abstract lists the study as "The effect of form on equine salt intake."

What the study actually did

Sixteen mature horses took part, split into two groups of eight. Each group alternated between a block and 4 lb of loose salt across four 7-day periods. Half of the horses had full turnout and half had partial turnout in individual paddocks, and the team measured salt and daily water intake.

The headline: the form of salt did not influence salt or water intake.

The NRC figure cited is roughly 25 g of salt a day for an 1,100-lb (500 kg) horse. About 56% of the horses did not meet it, even with free access to salt. The Equine Chronicle summary says horses falling short "may benefit from added salt in their ration."

Two cautions. This was 16 horses over short periods, so it is a useful signal, not the last word. And the study doesn't say what any one horse should get.

Why horses need salt

Salt is sodium chloride, and horses need both minerals every day. They help run nerves and muscles, and they keep fluid balance in order. Sodium also helps drive thirst, so a horse with enough salt tends to drink better.

Horses lose salt in sweat, and grass and hay are low in sodium. That is why a horse in hard work or hot weather needs more attention, and why "just put out a block" is not always enough.

How to offer salt: a free-choice checklist

Since form didn't change intake in the study, choose what is easiest to keep clean, dry and in front of the horse. In cold weather, though, University of Minnesota Extension suggests considering loose salt, because horses may not want to lick cold salt blocks.

• Offer plain salt at all times. A plain white block or a loose-salt feeder can both work, but in winter loose salt may be the easier one for your horse to use.
• Use one source per horse where you can. In a shared paddock, a dominant horse can guard the block while another never gets near it.
• Keep it dry and visible. Wet, caked or buried salt gets ignored. Check feeders after rain and snow.
• Mind the mineral type. Plain salt is not the same as a trace-mineral block. Check the label for what you are actually offering.
• Never take water for granted. Salt only helps if clean, unfrozen water is there too.
• Watch your own horse. Notice whether the block is licked, shrinking or untouched, and note it.

A block that never changes size is information. So is a bucket of loose salt that vanishes in a day.

Why fall and winter water matters

Cooler weather is when the study lands closest to home. Horses often drink less as temperatures fall, and dried winter forage holds far less moisture than summer pasture. University of Minnesota Extension notes that ponies drank about 40% more per day when water was above freezing.

Less water means drier gut contents, and impaction colic becomes more likely. Extension guidance adds that a horse doesn't develop an impaction in one day, but can over several days to weeks of poor drinking.

The study found water intake from 7 to 19 gallons a day between horses. That is a wide spread, and a reminder that you need to know your own horse's normal. For a general figure, UMN Extension says most 1,000-lb adult horses need at least 10 to 12 gallons daily.

Easy winter water habits

• Keep water from freezing, and break or heat ice at least twice a day.
• Offer water that isn't painfully cold. UMN Extension suggests roughly 45 to 65°F as ideal.
• Soak hay or add water to the feed if your vet suggests it.
• Pair the first cold snaps with a check of hay amounts. See our guide on how much hay a horse eats.

Signs a horse may not be drinking enough

These are clues, not a diagnosis. Any combination is a reason to look closer, and a call to your vet if it persists.

• Water bucket or trough level barely changes day to day.
• Drier, smaller or fewer manure piles than usual.
• Eating less hay, or leaving the coarse stems.
• Dull, quiet behavior or a slightly sunken look to the eyes.
• A skin pinch on the neck that is slow to flatten.
• Pawing, flank watching or lying down more than usual. These are colic signs: call the vet right away.

When to ask your vet or nutritionist

The study's message is that free access does not guarantee enough intake. That makes salt a good topic for your next vet visit or a consult with an equine nutritionist.

Ask if:

• Your horse rarely touches salt, block or loose.
• It is a hard worker, a heavy sweater or on a mostly forage diet.
• It has a history of impaction colic.
• Water intake drops each winter.
• You are changing hay, which is common with the 2026 hay squeeze.

They can decide whether adding salt to the ration makes sense and in what amount. Don't guess at quantities or add large amounts on your own, especially for a horse with a medical condition.

What to watch next

This week, spend five minutes at the stall or paddock. Look at your salt source, check your water setup, and write down what you see. Then, as the weather turns, compare it against your horse's normal.

For more feeding basics, see our nutrition guide and the care guide. If your horse is also changing weight with the season, read about the body condition score, and if you're deciding on layers, see when to blanket a horse.