Añasco is a town and municipality located on the west coast of Puerto Rico. It is situated north of Mayagüez and Las Marías, south of Rincón, Aguada, and Moca, and west of San Sebastián and Las Marías. The municipality borders the Mona Passage to its west.
The town was named in honor of one of its settlers, Don Luis de Añasco. It is currently part of the Aguadilla-Isabela-San Sebastián Metropolitan Statistical Area.