The Pisterzo post office was subordinate to the Piperno first class distribution office.
Pisterzo, July 8, 1870, Curia Fornea di Pisterzo origin marking, Piperno July 9 transit marking, Roma Ceprano Ambulante July 9 transit, and Ferrentino, July 9 backstamp. Used in the last months of the Papal States.
Pisterzo, October 8, 1874, Curia Fornea di Pisterzo origin marking, Frosinone October 9 transit marking, Ferrentino, October 9 backstamp. Used during the Kingdom of Italy.