(now known as Villa Santo Stefano)
Santo Stefano was a 2nd class distribution office, reporting to Frosinone. In 1871, Santo Stefano had a population of 1,335.
S[anto] Stefano, 1848, rated 1 bajocco to Ferentino. Frosinone transit marking, and negative parish marking on front.
S[anto] Stefano, July 1854, 1 bajocco black on blue green 1852 pays the rate for a single letter within the same direzione postale. Frosinone July 5, 1864 transit markings front and back, and Priori di S. Stefano markings on front and back.
S[anto] Stefano, April 10, 1858, no rate marking, but properly rated 1 bajocco to Ferentino. CURIA FORANEA SANTO STEFANO marking on front.
S[anto] Stefano, January 13, 1867, 2 bajocchi black on greenish white 1852, pays the reduced 2 bajocchi rate effective January 1, 1864. Frosinone January 13, 1867 transit marking on front. Roma arrival marking with indistinct date on back.
S[anto] Stefano marking used on Kingdom of Italy stamps in 1876.