Madame Mathilde Loisel has always imagined herself an aristocrat, despite being born into a family of clerks . Her husband is a low-paid clerk who tries his best to make her happy but has little to give. Still, the young couple can afford the services of a young Breton girl as a servant. After much effort, he secures for them an invitation to a ball sponsored by the Ministry of Education.
Madame Loisel refuses to go, for she has nothing to wear and does not want to be embarrassed. Loisel gives his wife 400 francs – all the money he had been saving to go hunting with his friends – so she can buy a dress. Even after Madame Loisel does so, she is still unhappy because she has no jewels to wear with it. She borrows a diamond necklace from her friend, Madame Jeanne Forestier.
Madame Loisel enjoys herself at the ball, dancing with influential men and reveling in their admiration. Once she and Loisel return home, though, she discovers that she has lost Jeanne's necklace. At the Palais-Royal shops, they find a similar necklace priced at 40,000 francs and bargain for it, eventually buying it for 36,000 francs. Loisel uses an inheritance from his father to cover half the cost and borrows the rest at high interest. Madame Loisel gives the necklace to Jeanne without mentioning the loss of the original, and Jeanne does not notice the difference.
Mr. Loisel and Madame Loisel live in poverty for ten years, with him taking on night work as a copier to earn extra money and her sacrificing her beauty to do household chores, while constantly bargaining with shop clerks and vegetable sellers. They gave up their servant, and moved to a dilapidated apartment up many flights of stairs. After all the loans were paid off, Madame Loisel encounters Jeanne on the Champs-Élysées, but Jeanne barely recognizes her due to her shabby clothing and unkempt appearance. Madam Loisel blames her former friend for the past miserable 10 years and tells Jeanne about the loss and replacement of the necklace. Jeanne reveals that the necklace she lent to Madame Loisel had contained fake diamonds and was worth no more than 500 francs.