Puerto Rico Senatorial District III, also known as the Senatorial District of Arecibo, is one of the eight senatorial districts of Puerto Rico. It is currently represented by José Pérez Rosa and Angel Martínez (both from the New Progressive Party).
The Senatorial District III has an approximate population of 470,250. It covers the following municipalities:
In previous distributions, the territory covered by the Senatorial District III has changed. In 1983, the District included the municipalities of Isabela and Morovis. In the 1991 redistribution, Isabela was assigned to the District of Mayagüez and Morovis to the District of Guayama. Meanwhile Toa Alta was assigned to Arecibo.
In the 2002 redistribution, Morovis was reassigned to the district while Toa Alta was reassigned to the District of Bayamón.