In topology, Costa's minimal surface is an embedded minimal surface and was discovered in 1982 by the Brazilian mathematician Celso Costa. It is also a surface of finite topology, which means that it can be formed by puncturing a compact surface. Topologically, it is a thrice-punctured torus.
Until its discovery, only the plane, helicoid and the catenoid were believed to be embedded minimal surfaces that could be formed by puncturing a compact surface. The Costa surface evolves from a torus, which is deformed until the planar end becomes catenoidal. Defining these surfaces on rectangular tori of arbitrary dimensions yields the Costa surface. Its discovery triggered research and discovery into several new surfaces and open conjectures in topology.
| author = Costa, Celso | title = Inmersos minimas completas em de gênero um e curvatura total finita | year = 1982 }} Ph.D. Thesis, IMPA, Rio de Janeiro, Brazil.
| author = Costa, Celso | title = Example of a complete minimal immersion in of genus one and three embedded ends | year = 1984 }} Bol. Soc. Bras. Mat. 15, 47–54.