While all nuts contain some potassium, pistachios, peanuts, almonds, cashew, walnuts, Brazil nuts, hazelnuts and chestnuts contain the most, according to SFGate. Pistachios have the highest level of potassium.
Pistachios contains 291 milligrams of potassium per 1-ounce serving, which is 6 percent of the daily recommended amount. Macadamia nuts and pecans contain the least amount of potassium, containing only 104 to 116 milligrams per serving, states SFGate.
Potassium helps regulate the heartbeat, lowers blood pressure and supports muscle and nerve function, according to SFGate. In addition to providing potassium, nuts are rich in zinc, magnesium, iron, unsaturated fat and protein.