The legal existence of this municipality as Calolbon can be manisfeted from the first Parish Priest on records, Rev. Fr. Cornelio de Jesus who ministered the town spiritual needs for 29 years starting April 1798. Then a bill renaming the town as San Andres was presented in Congress and was approved through Republic Act No. 3948 on June 18, 1964. From there the municipality known to be Calolbon was officially recognized as San Andres up to the present.