Salvatore "Big Pussy" Bonpensiero is played by Vincent Pastore. Big Pussy was a longtime close friend and mob enforcer for Tony Soprano, and was also shown to be close friends with fellow DiMeo crime family mobsters Paulie "Paulie Walnuts" Gualtieri, Silvio Dante, and was once a close friend to Tony's uncle Corrado "Junior" Soprano. In the tie-in video game it is revealed he has an illegitimate son named Joey LaRocca. Samson Moeakiola portrays a young Bonpensiero in the 2021 prequel film, The Many Saints of Newark. The son of Lino Bonpensiero, Salvatore Bonpensiero started out as a cat burglar, and was affectionately known as Pussy, in reference to those talents. He was called "Big Pussy" to distinguish from Gennaro "Little Pussy" Malenga. He operated an auto body shop with his brother Edward "Duke" Bonpensiero. Sal was a soldier in the Soprano crew, and he backed "Johnny Boy" Soprano's wishes to have Tony Soprano become capo following Johnny's death in 1986. In order to put his children through college, he dealt heroin on the side. Sometime between 19, Sal was caught by the FBI and decided to inform against the Soprano crew in order to avoid the possibility of life in prison. He was assigned Agent Skip Lipari as his handler. He was revealed as an informant in the episode " Do Not Resuscitate".
In flashbacks to 1995, it is shown that Sal was instrumental in organizing a sit-down between high ranking capo Junior Soprano and acting boss Jackie Aprile Sr. He traveled to Boca Raton to persuade Junior to return to New Jersey and settle a trucking dispute with Aprile. However, Sal was suspiciously late for the sit-down and blamed health problems of his comare's mother. In 1998, he was arrested at a card game run by Soprano family capo Jimmy Altieri. He tried to escape but threw his back out and was caught. He was quickly bailed out, but was confined to his home due to injury.
Dirty cop Vin Makazian told Tony he had a rat in his organization and pointed the finger at Sal. Tony assigned Paulie Gualtieri to investigate, and to kill Sal, but only if he explicitly saw proof. At a bath house with Paulie, Sal refused to undress, blaming high blood pressure and alleging it would be bad for his back, but implicitly suggesting (to the viewer) it could really be because he was wearing a wire. This raised the crew's suspicions further, especially after Sal then disappeared.
Paulie took over his collections, and the crew killed Altieri, taking the heat off Sal, as the crew figured the rat was flushed.