Act three begins with Kristine Linde talking to Nils Krogstad. It is clear that they had a previous relationship that she was forced to break off in order to marry another man who could support her family. It is also clear that he still loves her. During their conversation he realizes that she wrote him the note in order for him to come ask for his letter back so that Kristine could help Nora. However, Kristine changes her mind and decides that he should leave the letter because it is time that Nora told her husband the truth. She also reveals that she would like to get back together with Krogstad and help him raise his children. Krogstad responds that he's never been this happy in his life, and he leaves.

Kristine stays long enough to say hello to Nora and tell her that the letter is still there, and Nora needs to tell her husband about the loan. Then Kristine leaves. Torvald continues talking to his wife about how much fun he had at the party and how happy he is. Then Dr. Rank stops by on his way out to say good bye. After he leaves, Torvald goes to the mailbox and finds someone has tampered with it. He finds a calling card from Dr. Rank with a black cross above his name. Nora tells her husband that this symbol means that Dr. Rank has decided to lock himself up until he dies. Her husband decides to go off and read his letters while Nora prepares to leave without his knowledge.

Suddenly, he bursts back out of his study. Nora proclaims that she won't let him save her. He can't believe what she's done and blames her father's loose principles. Torvald proclaims that Nora has ruined his happiness, and he can no longer trust her to raise their children. Nora threatens to kill herself, but he says that act would not help him any. A maid then enters with a new letter from Krogstad. Torvald reads this letter, which says that Krogstad is sorry, he's had a change of heart, and he's returning the original note. Torvald proclaims that he's been saved, tears the contract up, and throws it in the fire. He then announces that he forgives his wife, who clearly needs more guidance and advise than he realized.

Nora tells him to sit down for a serious conversation, which she realizes they have never had before. She explains that Torvald has never understood her or really loved her the way he should have. He treated her like a doll, just the way her father did. She has realized that she needs to grow up and figure things out for herself; therefore, she has decided to leave. Torvald tries to reason with her, telling her that she can't leave her children or her husband. What will people think? However, Nora can't be concerned with those things. She needs to focus on herself. In the end she has realized that she doesn't really love Torvald. When he had the chance, he did not step up and try to protect her the way he said he always would. She decides she can't live with this stranger, so she gives him his ring back and says he no longer has any legal responsibility for her. When he asks what could happen to make her return, she says they would both need to change, so as she leaves, Torvald wonders if that is possible.