Act Four opens in a Salem jail cell. It is the day when Rebecca Nurse and John Proctor are to be hanged. Both have resisted confessing up to that point, but Rev. Hale – unseen at the court since Proctor's arrest – is trying to encourage their confession. Even though he knows their confession would be a lie, he wants to save their lives. Rev. Parris is also trying to get them to confess, but that is because he wants to save his own life: since the trials began, Parris has received some not-so-subtle threats to his life. To make matters worse, Abigail has fled, taking all of Parris's money with her. Since Proctor went to jail, over one hundred people have restored their lives by "confessing" to witchcraft, but the town is in shambles. There are orphans, livestock wandering all over the place, and people bickering over who gets whose property.
Judges Hawthorne and Danforth call upon Elizabeth, still imprisoned, and now obviously pregnant, to talk to her husband to see if she can get him to confess. When Elizabeth agrees to speak with Proctor (who has been in the dungeon, separated from the other accused), the couple finally gets a few private moments alone in the courthouse. Elizabeth reaveals that Giles, who refused to give a plea, was pressed by stones and died. Because he did not say if he was guilty or not guilty to the charges, his sons are entitled to inherit his land. In these warm exchanges, Elizabeth says she will not judge what Proctor decides to do, and affirms that she believes he is a good man. While Elizabeth will not judge Proctor, she herself cannot confess to witchcraft, as it would be a lie. Proctor asks for Elizabeth's forgiveness, and she says he needs to forgive himself. Elizabeth blames herself for the affair, claiming to be a “cold wife." She asks John for forgiveness and says she has never known such goodness in all her life as his. At first, this gives Proctor the determination to live, and he confesses verbally to Danforth and Hathorne. The men bring Rebecca to witness Proctor’s confession, hoping that she will follow his example. The sight of Rebecca shames Proctor. Proctor cannot bring himself to sign the “confession”. Knowing that the confession will be pinned to the church door for his sons and other community members to see is too much for Proctor to bear. Nor will he incriminate anyone else as a witch. After he signs the confession he snatches it from Danforth. He believes it should be enough to confess verbally and only incriminate himself. Proctor pleads with the court, who have taken his soul and his life, to leave his name. When the court refuses this, Proctor, deeply emotional, tears up the written confession. Shocked, Hale and Parris plead with Elizabeth to talk sense into her husband, but she realises that this is, at last, his moment of redemption: “He have his goodness now. God forbid I take it from him!” And so he goes to his death. The curtain falls just before John Proctor is hanged.