How much potassium is in whole milk?
Whole milk has 322 mg of potassium per 1 cup (244 g) — about 7% of the 4,700 mg Daily Value. That's 132 mg per 100 g, roughly 0.8× a medium banana (~422 mg).
USDA FoodData Central · 3.25% milkfat · FDC 171265
Potassium by portion
| Portion | Potassium | % DV | Sodium | Calories |
|---|---|---|---|---|
| 1 cup (244 g) | 322 mg | 7% | 105 mg | 149 |
| 100 g | 132 mg | 3% | 43 mg | 61 |
| 1 oz (28 g) | 37 mg | 1% | 12 mg | 17 |
% DV against the FDA Daily Value of 4,700 mg of potassium. Whole foods are naturally potassium-rich and low in sodium — the ratio heart guidelines (like DASH) favor. Values from USDA per-100 g data (FDC 171265, SR Legacy). 3.25% milkfat.
Milk almost never comes up when people list potassium foods — they reach for bananas — but a glass quietly competes. One cup of whole milk (244 g) carries about 322 mg of potassium, which is 132 mg per 100 g and roughly 7% of the 4,700 mg Daily Value. That’s about 0.8× a medium banana (~422 mg) per cup, and since people rarely stop at a single cup, the day’s total climbs faster than the fruit. A 16 oz glass alone clears a banana and a half.
Why milk is a quietly useful potassium source
Potassium is the blood-pressure mineral — it counterbalances sodium and helps relax blood-vessel walls — and milk has a couple of advantages the banana doesn’t. First, the DASH eating pattern, the diet specifically built around lower blood pressure, names low-fat dairy as a deliberate source of both potassium and calcium; milk isn’t a workaround here, it’s a recommended component. Second, milk is naturally low in sodium (~43 mg per 100 g) while carrying its potassium, so it lands on the favorable side of the sodium-to-potassium ratio heart guidance cares about. And it’s effortless to drink more than one serving — over cereal, in a shake, in coffee — so milk’s potassium stacks up across a day in a way a single banana doesn’t.
Whole vs. 2% vs. skim, and the honest framing
The fat percentage on the carton doesn’t touch the potassium. Whole, 2%, 1% and skim all sit near 130–150 mg per 100 g — about 320–360 mg a cup — with skim running a hair higher only because removing fat slightly concentrates everything else. So the milk you pick changes the fat and calories, not the potassium. The fair way to frame it: milk is a contributor, not a potassium champion like a potato (~951 mg) — but it’s an easy, low-sodium, calcium-carrying contributor that most people overlook entirely. A couple of cups across the day is a genuine, painless nudge toward 4,700 mg. (One note for context, not alarm: people with kidney disease are sometimes advised to limit potassium, so this is reference data rather than medical advice.)
For the side of milk people usually buy it for — and why it’s a protein base rather than a high-protein drink — see protein in whole milk.
Packaged milk options, graded
Prefer something off the shelf? Here are the best-graded milk in our catalog — each scored on our transparent Labelgrade.
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Labelgrade 80/100 · 8 g protein
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Labelgrade 78/100 · 8 g protein
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Frequently Asked Questions
How much potassium is in a cup of whole milk?
About 322 mg of potassium in one cup (244 g), based on 132 mg per 100 g (USDA FDC 171265). A tall 16 oz glass carries closer to 630 mg — roughly a banana and a half's worth — which is why milk is a quietly meaningful potassium source.
What percent of the Daily Value is that?
Roughly 7% of the 4,700 mg Daily Value for potassium in one cup. That's a solid contribution from a drink, especially since milk also brings calcium — and unlike a banana, a couple of cups across the day add up without anyone thinking of milk as a potassium food.
How does whole milk's potassium compare to a banana?
A cup of whole milk has about 322 mg, roughly 0.8× the potassium of a medium banana (~422 mg). A 16 oz glass edges past one and a half bananas. So milk isn't quite banana-for-banana per cup, but it's in the same league — and easy to drink more than one cup of.
Do whole, 2%, and skim milk differ in potassium?
Hardly at all. The fat percentage doesn't change the potassium, so whole, 2%, 1% and skim all sit near 130–150 mg per 100 g, about 320–360 mg a cup. If anything, skim runs a touch higher because removing fat slightly concentrates everything else — but the difference is small.
Why does potassium matter, and does milk help blood pressure?
Potassium counterbalances sodium and helps relax blood-vessel walls, and the DASH eating pattern built around lower blood pressure specifically includes low-fat dairy as a potassium and calcium source. Milk is also naturally low in sodium (~43 mg per 100 g), so it sits on the favorable side of that ratio. This is general nutrition information, not medical advice.
When was this data last verified?
2026-06-18, against USDA FoodData Central FDC 171265 (Milk, whole, 3.25% milkfat; SR Legacy). We re-verify reference pages periodically and update if the USDA record changes.
Whole-food values are USDA reference data, not a Labelgrade (that score is for branded packaged products). High-potassium diets aren't for everyone — people with kidney disease are often told to limit it; this is reference data, not medical advice. See our methodology.