Coinco is a Chilean commune and town in Cachapoal Province, O'Higgins Region.

[5] According to the 2002 census of the National Statistics Institute, Coinco has 6,385 inhabitants (3,293 men and 3,092 women).

[2] As a commune, Coinco is a third-level administrative division of Chile administered by a municipal council, headed by an alcalde who is directly elected every four years.

[1] Within the electoral divisions of Chile, Coinco is represented in the Chamber of Deputies by Eugenio Bauer (UDI) and Ricardo Rincón (PDC) as part of the 33rd electoral district, together with Mostazal, Graneros, Codegua, Machalí, Requínoa, Rengo, Olivar, Doñihue, Coltauco, Quinta de Tilcoco and Malloa.

The commune is represented in the Senate by Andrés Chadwick Piñera (UDI) and Juan Pablo Letelier Morel (PS) as part of the 9th senatorial constituency (O'Higgins Region).