Onion Salt Substitutes: How Much Salt and Onion to Use Instead

Onion salt seasons a dish the way salt does, with onion on top. McCormick’s lists salt, onion, an anticaking agent and extractives of onion, and carries 440 mg of sodium per 1/4 teaspoon,¹ about three-quarters of the 590 mg in the same measure of Morton’s iodized table salt.² So a substitute has two parts to get right: most of a measure of salt, and some onion. Get the salt wrong and the dish is bland or oversalted; the onion is more forgiving.

Quick answer

How the ratios on this page are labeled

• Computed: based on a measurable physical relationship, with the source named.
• Attributed: a named source publishes this ratio. We quote it as theirs.
• Disputed: named sources give different answers to the same swap. We show each one and do not average them.
• Method: we found no published ratio. We give a direction and a cautious starting point, and say so.

The salt figures are computed from the sodium on brand labels. They match sodium, not flavor. No label gives the proportion of salt to onion in an onion salt, so the onion figures come from NDSU Extension’s substitution chart, which treats 1 1/3 teaspoons of onion salt, 1 teaspoon of onion powder and 1 to 2 tablespoons of minced dried onion as each equal to one small onion.³

Match the salt first

Salt (Computed): One teaspoon of McCormick onion salt carries about 1,760 mg of sodium (4 × 440 mg).¹ One teaspoon of Morton table salt carries 2,360 mg (4 × 590 mg).² To match the sodium, use 3/4 teaspoon of table salt for each teaspoon of onion salt.

For a different brand, divide its sodium per 1/4 teaspoon by 590 to get teaspoons of table salt per teaspoon of onion salt. Kosher and flaky salts hold less salt per spoon, because fewer large crystals fit;⁴ if you use one, add a little more by volume and taste.

If onion salt is seasoning a dry dish

1. Table salt plus onion powder

This is the closest substitute, since onion salt is salt plus dried onion.¹ Plain onion powder adds almost no sodium of its own: 73 mg per 100 g in USDA’s data.⁵

Onion (Attributed): By NDSU’s chart, 1 1/3 teaspoons of onion salt and 1 teaspoon of onion powder do the same job,³ which works out to 3/4 teaspoon of onion powder per teaspoon of onion salt (our arithmetic). That chart is an onion equivalent, not a recipe for the blend, and it may give more onion flavor than your jar did. In our judgment, start with 1/2 teaspoon of powder alongside the 3/4 teaspoon of salt and add the rest after tasting.

Stir the two together before you measure them into a rub, so the salt and onion spread evenly.

2. Table salt plus dried minced onion

Onion (Attributed): NDSU’s chart gives 1 to 2 tablespoons of minced dried onion for the same small onion as 1 1/3 teaspoons of onion salt.³ Per teaspoon of onion salt, that is about 2 1/4 to 4 1/2 teaspoons of minced onion (our arithmetic). NMSU’s chart, which has no onion salt row, sets 1 tablespoon of instant minced onion against a small onion,⁶ which lands at NDSU’s low end. Start there. Grind it first for a rub or a smooth dressing. For how dried minced onion compares with powder, where the extension charts disagree, see onion powder substitutes.

Add the 3/4 teaspoon of table salt as above.

If onion salt is seasoning a wet dish

Table salt plus fresh onion

In soups, stews, dressings and dips, fresh onion works and blends into the liquid.

Onion (Attributed): NDSU sets 1 1/3 teaspoons of onion salt against one small onion, or 1/4 cup of chopped fresh onion.³ Per teaspoon of onion salt, that is about three-quarters of a small onion, or 3 tablespoons chopped (our arithmetic). Grate it finely if the dish is smooth.

Salt (Computed): Add 3/4 teaspoon of table salt per teaspoon of onion salt, as above. Don’t leave it out: the salt is most of what onion salt does.

Water: A small onion weighs 70 g in USDA’s data and raw onion is 89.1 percent water,⁷ so three-quarters of a small onion brings about 47 g of water, roughly 3 tablespoons (our arithmetic). In a thin soup that doesn’t matter; in a dip or a dressing, it will loosen the texture. Expect a sharper, fresher onion flavor than onion salt gives.

Onion juice and salt

Ratio (Method): We found no published ratio. Add the table salt from above, then onion juice a teaspoon at a time, tasting as you go. It adds liquid but no texture.

If you want a ready-made shaker

Seasoned salt

Seasoned salt is another salt-first blend, and it contains onion along with much else. Lawry’s The Original Seasoned Salt lists salt, sugar, spices including paprika, celery seed and turmeric, onion, corn starch and garlic, and carries 380 mg of sodium per 1/4 teaspoon.⁸

Ratio (Computed for sodium, Method for flavor): Used at the same volume, Lawry’s carries about 86 percent of the sodium of McCormick onion salt (380 ÷ 440). Start with the same volume and taste. It adds sweetness, color and garlic as well as onion, so it suits burgers, fries and roast potatoes better than a delicate dressing; that is our judgment.

Celery salt

Celery salt is salt and celery seed; McCormick’s lists only those two ingredients, with 270 mg of sodium per 1/4 teaspoon.⁹ Its flavor is celery’s, which comes from compounds called phthalides,¹⁰ not onion’s. Use it only where the dish suits celery, such as a potato salad or a Bloody Mary.

Salt (Computed): Used at the same volume, McCormick celery salt carries about 61 percent of the sodium of McCormick onion salt (270 ÷ 440). To make up the difference, add about 1/4 teaspoon of table salt per teaspoon of celery salt (the remaining 680 mg ÷ 2,360 mg per teaspoon of table salt is 0.29).

What isn’t known

• No onion salt label gives its ratio of salt to onion, so the onion amounts on this page come from NDSU’s substitution chart rather than from a commercial blend.
• No study compares the flavor strength of onion salt with onion powder, fresh onion or onion juice.
• Only one onion salt label (McCormick) was checked. Check the sodium on yours.

Related

• Onion salt, onion powder and onion salt vs. onion powder
• Onion powder substitutes and onion powder vs. onion
• Garlic salt substitutes, celery salt substitutes and seasoned salt
• Celery salt, table salt and too much salt

Footnotes

1. McCormick Onion Salt, label ingredients and Nutrition Facts as listed by Stop & Shop. stopandshop.com · Merchant ↩ ↩² ↩³

2. Morton Iodized Table Salt, Nutrition Facts, Morton Salt. mortonsalt.com · Merchant ↩ ↩²

3. Julie Garden-Robinson, Ingredient Substitutions (FN198), NDSU Extension, 2018. ksre.ksu.edu · Reference work ↩ ↩² ↩³ ↩⁴

4. Sodium Sources: Where Does All That Sodium Come From?, American Heart Association, 2025. heart.org · Reference work ↩

5. Spices, onion powder (FDC 171327), USDA FoodData Central. fdc.nal.usda.gov · Regulator ↩

6. In a Pinch Ingredient Substitution (E-131), NMSU Cooperative Extension, 2016. pubs.nmsu.edu · Reference work ↩

7. Onions, raw (FDC 170000), USDA FoodData Central. fdc.nal.usda.gov · Regulator ↩

8. Lawry’s The Original Seasoned Salt, label ingredients and Nutrition Facts as listed by ShopRite. shoprite.com · Merchant ↩

9. McCormick Celery Salt, label ingredients and Nutrition Facts as listed by Stop & Shop. stopandshop.com · Merchant ↩

10. Salehi et al., Apium Plants: Beyond Simple Food and Phytopharmacological Applications, Applied Sciences, 2019. mdpi.com · Peer-reviewed ↩