Milk DOES have potassium.
Milk contains 377 milligrams of potassium per cup, which is a good start to fulfilling the daily needs for an adult of about 2,000 milligrams.
Potassium is present in a variety of foods including milk, meats, vegetables and fruits. If you are looking for high impact potassium foods add papaya at 781 milligrams or a cup of prune juice, which packs 707 milligrams. Other good dietary sources of potassium include tomato juice (535 mg), sweet potato (508 mg), one-half avocado (450), one-half cup pinto beans (400 mg), six ounces of yogurt (398 mg), or three ounces of baked salmon (319 mg).