Pasto is a rural barrio in the municipality of Guayanilla, Puerto Rico. Its population in 2010 was 327.
Pasto has of land area and no water area. In 2010, its population was 327 with a population density of .
Pasto was in Spain's gazetteers until Puerto Rico was ceded by Spain in the aftermath of the SpanishâÂÂAmerican War under the terms of the Treaty of Paris of 1898 and became an unincorporated territory of the United States. In 1899, the United States Department of War conducted a census of Puerto Rico finding that the population of Pasto barrio was 1,276.