Ingredientskim milk
The call
Use milk
for skim milk.
Use 1:1 in most batters and sauces; when swapping between buttermilk and sweet milk, either acidify the sweet milk (1 tbsp vinegar or lemon juice per cup, rest 5 minutes) or adjust the baking soda so the leavening still balances.
Last verified 2026-05-06 against King Arthur Baking: How to substitute for buttermilk: Reviewed 2026-05-06 against King Arthur Recipe Success Guide (treats whole, reduced-fat, low-fat, and skim milk as largely interchangeable in baking) and King Arthur buttermilk substitute guide (acidified-milk technique: 1 tbsp vinegar or lemon juice per cup of milk, rested 5 minutes; reduce baking soda or replace with baking powder when buttermilk is replaced by sweet milk so the recipe is not over- or under-leavened).
Ratio
1 : 1
Why this works
Dairy milks swap most cleanly when both fat level and acidity stay close to the original ingredient; whole, reduced-fat, low-fat, and skim milk are largely interchangeable in baking, while buttermilk needs an acid boost or a leavener tweak when paired against sweet milk.
Sensory diff
- Flavor
- Usually mild; richer milks taste fuller, and goat or sheep milk adds a noticeable barnyard or tangy note.
- Texture
- Lower-fat options can thin crumb and body; buttermilk thickens batter slightly.
Nutrition diff
per 100ml
| Macro | skim milk | milk | Δ |
|---|---|---|---|
| Calorieskcal | 34 | 61 | +79% |
| Proteing | 3.4 | 3.2 | -6% |
| Fatg | 0.1 | 3.3 | +3200% |
| Sat. fatg | 0.1 | 1.9 | +1800% |
| Carbsg | 5 | 4.8 | ≈ |
| Sugarg | 5.1 | 5.1 | ≈ |
| Fiberg | — | 0 | — |
| Sodiummg | 42 | 43 | ≈ |
General reference, not medical advice. Sourced from USDA FoodData Central.
Alternatives, ranked
4 more options
- Low1 : 1·A·0.94·kcal +79%
Whole, reduced-fat, low-fat, and skim milk swap 1:1; buttermilk needs an acid step or a baking-soda tweak.
Last verified 2026-05-06 against King Arthur Baking: How to substitute for buttermilk: Reviewed 2026-05-06 against King Arthur Recipe Success Guide (treats whole, reduced-fat, low-fat, and skim milk as largely interchangeable in baking) and King Arthur buttermilk substitute guide (acidified-milk technique: 1 tbsp vinegar or lemon juice per cup of milk, rested 5 minutes; reduce baking soda or replace with baking powder when buttermilk is replaced by sweet milk so the recipe is not over- or under-leavened).
- High1 : 1; from buttermilk add 1 tbsp acid per cup·B·0.83·kcal +47%
Plant milks swap 1:1, but soy mimics dairy milk best; oat, almond, rice, and cashew can fall short when the recipe leans on dairy protein.
Last verified 2026-05-07 against King Arthur Baking: Non-dairy milk for baking: Reviewed 2026-05-06 against King Arthur Baking 'Non-dairy milk for baking' (soy matches dairy's ~8 g/cup protein and whole-milk viscosity; soy yields the most dairy-like custard with oat as second; almond, rice, and cashew read neutral in bread but bring minimal protein) and King Arthur 'How to bake dairy-free' (most plant milks fall short in egg- or starch-thickened custards; high-fat coconut or cashew milk delivers custard-like body in puddings and rich fillings). 2026-05-07 SWP-019 directionality pass: added a per-source carve-out for buttermilk-side sources (buttermilk, cultured buttermilk, acidified milk in the milk-dairy group) because the original rule text was sweet-milk-source only and missed the acidification step required when going from an acidic source to a pH-neutral plant milk. Anchored against King Arthur Baking 'How to substitute for buttermilk' (the standard 1 tbsp acid + 1 cup milk, rest 5 minutes, gives an acidified-milk stand-in; the same technique works in reverse to acidify plant milk so it behaves like buttermilk in soda-leavened recipes). Carve-out lives in ratioText, ratioShort, explanationLong, failureRisk, and a new [acidity] adjustment so the buttermilk → plant-milk pages render the acidification advice without affecting the milk → plant-milk pages (which still see the 1:1 sweet-milk framing as the lead). confidenceScore and confidenceTier left at 0.83 / B because this is a directional accuracy fix, not a fresh confidence calibration.
- Low1 : 1·A·0.94·kcal +47%
Whole, reduced-fat, low-fat, and skim milk swap 1:1; buttermilk needs an acid step or a baking-soda tweak.
Last verified 2026-05-06 against King Arthur Baking: How to substitute for buttermilk: Reviewed 2026-05-06 against King Arthur Recipe Success Guide (treats whole, reduced-fat, low-fat, and skim milk as largely interchangeable in baking) and King Arthur buttermilk substitute guide (acidified-milk technique: 1 tbsp vinegar or lemon juice per cup of milk, rested 5 minutes; reduce baking soda or replace with baking powder when buttermilk is replaced by sweet milk so the recipe is not over- or under-leavened).
- High1 : 1; from buttermilk add 1 tbsp acid per cup·B·0.83·kcal ≈
Plant milks swap 1:1, but soy mimics dairy milk best; oat, almond, rice, and cashew can fall short when the recipe leans on dairy protein.
Last verified 2026-05-07 against King Arthur Baking: Non-dairy milk for baking: Reviewed 2026-05-06 against King Arthur Baking 'Non-dairy milk for baking' (soy matches dairy's ~8 g/cup protein and whole-milk viscosity; soy yields the most dairy-like custard with oat as second; almond, rice, and cashew read neutral in bread but bring minimal protein) and King Arthur 'How to bake dairy-free' (most plant milks fall short in egg- or starch-thickened custards; high-fat coconut or cashew milk delivers custard-like body in puddings and rich fillings). 2026-05-07 SWP-019 directionality pass: added a per-source carve-out for buttermilk-side sources (buttermilk, cultured buttermilk, acidified milk in the milk-dairy group) because the original rule text was sweet-milk-source only and missed the acidification step required when going from an acidic source to a pH-neutral plant milk. Anchored against King Arthur Baking 'How to substitute for buttermilk' (the standard 1 tbsp acid + 1 cup milk, rest 5 minutes, gives an acidified-milk stand-in; the same technique works in reverse to acidify plant milk so it behaves like buttermilk in soda-leavened recipes). Carve-out lives in ratioText, ratioShort, explanationLong, failureRisk, and a new [acidity] adjustment so the buttermilk → plant-milk pages render the acidification advice without affecting the milk → plant-milk pages (which still see the 1:1 sweet-milk framing as the lead). confidenceScore and confidenceTier left at 0.83 / B because this is a directional accuracy fix, not a fresh confidence calibration.
Adjustments
- fat-balance
- Add a little fat when moving from whole milk to a lower-fat option.
- acidity
- When swapping sweet milk in for buttermilk, stir 1 tablespoon of vinegar or lemon juice into 1 cup of milk and rest 5 minutes; in the reverse direction, reduce baking soda or replace it with baking powder so the recipe is not over-leavened.
Where to be careful
- Lowmilk — Low, unless the recipe depends on buttermilk acidity to react with baking soda.
- Lowwhole milk — Low, unless the recipe depends on buttermilk acidity to react with baking soda.
- Highoat milk — Medium overall; high in egg- or starch-thickened custards and pastry creams unless the milk is soy or a high-fat option like full-fat coconut. From buttermilk: high in soda-leavened pancakes, biscuits, and quick breads unless the plant milk is acidified or the leavening is rebalanced.