San Pietro Apostolo was administered by its neighbor Tiriolo until the end of the 18th century when it obtained its autonomy under law No. 14 of 19 January 1807. It was elevated to the status of a comune with the name of 'San Pietro a Tiriolo' and placed under the jurisdiction of what was then called Calabria Ulteriore, which consisted of the current provinces of Catanzaro, Crotone, Reggio Calabria and Vibo Valentia. On 4 May 1811 the comune was given the name of San Pietro Apostolo, attesting its separation from Tiriolo which remained, however, the administrative seat. Law No. 360 of 1 May 1816 transferred the village of San Pietro Apostolo with its 1992 inhabitants from the administration of Tiriolo to that of Gimigliano, and from the province of Calabria Ultra to the new province of Calabria Ultra Seconda (Catanzaro).