Patrica was a 2nd class distribution office, reporting to Frosinone. In 1871, Patrica had a population of 2,696.
Patrica, July 27, 1845, stampless cover to Anagni, rated 1 bajocco for a letter within the same direzione postale. Frosinone straight-line transit marking on front, and 30 July transit marking date applied at Frosinone on back.
Patrica, January 21, 1851, straightline postmark in red on stampless cover to Ferentino, rated 3 bajocchi. Indistinct Frosinone transit marking on front.
Patrica, May 22, 1855, 1 bajocco black on blue green 1852 pays the rate for a single letter within the same direzione postale.
Patrica, 1872, Curia Foranea imprint, with no other postal markings.
Patrica, January 21, 1873, use of the Papal States straightline postmark in the Kingdom of Italy. Frosinone, January 22, 1873 transit mark with month inverted, Ferentino, January 23, 1873 arrival marking on back.
Patrica, February 1874 use of the Papal States straightline postmark in the Kingdom of Italy, with Vittorio Emanuele II Re D'Italia, Municipio di Patrica seal. Ceccano February 23, 1874 transit mark, Roma February 28, 1874, and Guarcino March 1, 1874 transit marks on back.