Estelle Sapir (c. 1926 – 13 April 1999) was a Polish Jewish Holocaust survivor who achieved a measure of fame for her successful battle with the Swiss banking industry, in particular Credit Suisse, after a half-century of fighting for the return of her family's money, which had been deposited by her father, Józef Sapir, before he was sent to his death in the Nazi concentration camp at Majdanek during World War II. 
In 1998, Credit Suisse -- which had demanded her father's death certificate, which did not exist due to the circumstances of Józef Sapir's murder in a concentration camp, in order to release the funds -- and Ms. Sapir jointly announced that the case was settled. The amount was not disclosed due to a confidentiality agreement but has been estimated at $500,000 USD.
Sapir died in 1999 in Rockaway, Queens from a heart attack after a period of poor health. She was believed to be 73 years old. She never married and was survived by two nieces and a nephew. She maintained her Polish citizenship until her death and was a permanent resident alien in the United States, not a naturalized U.S. citizen, unlike her fellow co-plaintiffs.
- Honan, William H. (16 April 1999). "Estelle Sapir, 73, Who Fought Bank Over Holocaust Assets". The New York Times. Archived from the original on 2 July 2010. Retrieved 2 July 2010.