Metallic potassium was first obtained by Sir Humphrey Davy, in 1807, by electrolysis of potassium hydroxide. He called it potassium from the English term "potash" ("pot" - recipient + "ash" - ashes), the name given to potassium carbonate obtained by lixiviation and evaporation in iron recipients of the wood and plant ashes.

Ever since, the potassium has been progressively replaced by sodium, in most of the salts with industrial applications, with exception of the cases where the specific properties of potassium salts are required, as it is the case of the fertilizer industry.