The third act takes place nine years later in the summer of 1913. The Stage Manager explains how things have slowly changed in that time, such as fewer horses on Main Street and people locking their doors at night. He walks into the cemetery and points out the gravestone of Mrs. Gibbs, Mrs. Soames, and Mr. Stimson. Emily's younger brother Wally has also died of a burst appendix while on a Boy Scout trip. The Stage Manager explains how the dead don't stay interested in the living for very long. They become weaned away from life on earth.

     Joe Stoddard, the undertaker, is checking a newly dug grave when Sam Craig, who used to live in Grover's Corners, walks up to him. Sam explains that he's been living in Buffalo for the last twelve years, but he came home when he heard his cousin had died. Sam notices the grave of Farmer McCarty, a man he used to do chores for when he was young. He also sees Mrs. Gibbs's, his aunt's, grave, and Joe says that she died two or three years ago.

     The dead people sit on chairs in the back of the cemetery during this act. They calmly speak to one another as they watch the living people. Mrs. Gibbs notices her sister's son, Sam, and points it out, but Mr. Stimson says the living people make him uncomfortable.

     Sam notices Mr. Stimson's grave and says he heard that he drank a lot. Joe agrees but admits that Mr. Stimson hung himself in his attic. He chose his own epitaph, which are just some musical notes. Then Sam asked what his cousin died of, and Joe tells him that she was giving birth to her second child. She already had a four-year-old boy.

     Mrs. Soames asks Mrs. Gibbs who is it that recently died, and Mrs. Gibbs tells her it is her daughter-in-law Emily Webb. Mrs. Soames recalls how awful and wonderful life can be. Emily walks up and says hello to the dead people. She notes that it is raining. Mrs. Gibbs tells her to sit down. Emily tells Mrs. Gibbs what they did after Mrs. Gibbs died. Mrs. Gibbs left them three hundred fifty dollars for an inheritance, so they fixed up the farm and built a cement fountain for the livestock. There's a device on the fountain so that it doesn't ever overflow. Emily realizes that living people don't really understand what's important or appreciate life. They are in the dark and troubled.

     Emily figures out that she can go back and relive moments of her life if she wants, but Mrs. Gibbs warns her not to. Emily goes up to the Stage Manager and asks him if it's true, and he says it is but that those who do return quickly. The Stage Manager explains that she would not only live it, but she would watch herself living it. Mrs. Gibbs tells her that it's better to forget that life and look ahead. Emily promises she'll choose a happy day, but Mrs. Gibbs warns her not to do that. She encourages her to choose a completely unimportant day. Emily decides to pick her twelfth birthday.

     The Stage Manager sets the scene for February 11, 1899. Emily sees the town as it used to be. She sees her mother calling her down to breakfast and is amazed by how young she looks. Her father walks in having returned from a business trip to New York. Emily comes down the stairs, and her mother tells her there are presents waiting for her. The dead Emily struggles to watch this piece of her life. George had come over early that morning to leave a gift for her, which Emily had forgotten about. As her mother speaks, the deceased Emily notices that her mother never really looks at her. Instead she bustles about the kitchen making breakfast when Emily wants her to just stop and appreciate the moment. She wants to be able to tell her the future: warn her about how her brother dies, tell her how she becomes a grandmother one day. When her father asks for his birthday girl, Emily can't stand it anymore. Life goes so quickly, and people don't realize it. They don't notice the little things, so Emily says goodbye.

     Emily asks the Stage Manager if humans ever realize the meaning of life while they actually live it, and the Stage Manager says that perhaps some saints or poets do. Mrs. Gibbs asks Emily if she was happy, and she says no. Mr. Stimson says that she has learned that people go through life in ignorance, blind to what's important. Then Emily sees George walk up to her grave and collapse crying onto the ground. The Stage Manager ends the play by talking about the stars and talking about how people need to sleep at the end of each day due to the strain of life. He ends by saying good night.