Arnis (, ) is a small town in the district of Schleswig-Flensburg, in Schleswig-Holstein, Germany. It is part of the Amt Kappeln-Land. It was founded in 1667. The local Skipper's Church was erected in 1673. At a population of c. 300 and a total area of 0.45 km², Arnis is the smallest town in Germany both by population and by area.