Buttermilk Substitute: Lemon Juice or Vinegar Plus Milk

What It Means

A buttermilk substitute is a mix you make at home when a recipe calls for buttermilk and there's none in the fridge. The standard version on extension and baking charts is 1 tablespoon of lemon juice or vinegar with enough milk added to make 1 cup, left to stand for 5 minutes. King Arthur Baking also lists sour cream thinned with milk or water until it's about as thick as heavy cream.

Try It: Mix It and Time the 5-Minute Rest

Enter how much buttermilk the recipe needs, mix it, then start the 5-minute rest.

Buttermilk needed (cups)

Lemon juice or vinegar (tablespoons)1

Then milk up to the line (cups)1

Rest5:00

Put the acid in first, then pour milk to the line, so the total stays at the amount the recipe needs.

How It Sounds at Home

"The pancakes call for buttermilk and we never have any."
"Just sour some milk with a bit of lemon juice."
"Give it five minutes to sit."

The Breakdown

How to make it (for 1 cup)

Pour 1 tablespoon of lemon juice or vinegar into a liquid measuring cup.
Add milk until the level reaches the 1-cup line.
Stir, then let it stand for 5 minutes.
Use it in place of 1 cup of buttermilk.

Try it today. Next time you make pancakes, mix the substitute first and let it sit while you measure the dry ingredients, so the wait overlaps with work you'd be doing anyway.

Scaled amounts. The ratio is 1 tablespoon of acid per cup, measured the same way each time.

Buttermilk needed	Lemon juice or vinegar	Then milk up to
½ cup	½ tablespoon	the ½-cup line
1 cup	1 tablespoon	the 1-cup line
2 cups	2 tablespoons	the 2-cup line
3 cups	3 tablespoons	the 3-cup line

If you have sour cream instead. King Arthur Baking suggests thinning sour cream with milk or water until it's about as thick as heavy cream, then using it in place of buttermilk.

Good to Know

Measure the acid first and fill with milk to the line. Pouring a full cup of milk on top of the tablespoon of acid gives you a little more liquid than the recipe was written for. The charts named on this page treat the 5-minute rest as part of the swap, so give it the full time.

FAQ

How do you make buttermilk with vinegar?

Put 1 tablespoon of vinegar in a measuring cup, add milk to the 1-cup line, stir, and let it stand 5 minutes. Lemon juice works the same way.

How long does a buttermilk substitute need to sit?

The substitution charts named on this page say 5 minutes. Stir it before you add it to the recipe.

Can I use sour cream instead of buttermilk?

Yes, thinned first. King Arthur Baking suggests adding milk or water to sour cream until it's about the thickness of heavy cream.

Do It in Buhata

Focus, Shopping

Set a 5-minute countdown in Focus in Buhata while the milk and lemon juice stand.

Open Buhata

Related Terms and Categories

Ingredient substitutions
Replacing an ingredient you don't have with another in a measured amount, such as all-purpose flour and cornstarch in place of cake flour.
Egg substitute
(1) A carton product made from egg whites, sold in place of whole eggs; (2) any ingredient, like flax meal and water, used instead of egg in a recipe.
Baking powder vs baking soda
Baking soda is a base that needs an acid in the recipe to make it rise; baking powder is baking soda already mixed with its own acid.
Recipe scaling
Changing how much a recipe makes by multiplying every ingredient by one conversion factor: the yield you want divided by the yield it makes.

Meal planning, groceries and kitchen

Sources

UNL Food (University of Nebraska-Lincoln Extension), "Basic Ingredient Substitutions"; Iowa State University Extension and Outreach, AnswerLine, "Substitutions for Common Foods"; King Arthur Baking, "Buttermilk substitute: What to use" and "How to substitute for buttermilk"

Last updated September 30, 2026.