Kelmis (in French: La Calamine) is a municipality located in the Belgian province of Liège. On January 1, 2006, Kelmis had a total population of 10,396. The total area is 18.12 km² which gives a population density of 574 inhabitants per km².
The territory around the Vieille Montagne zinc mine in Kelmis was semi-independent during 1816–1919 as Neutral Moresnet, with the Mayor of Kelmis as head of state.
In the nineteenth century a Low Dietsch dialect was spoken in Kelmis. Today Kelmis is bilingual: German and French and one of the nine municipalities of the German-speaking Community of Belgium.