Stefania Zacharska was born on 25 November 1906 in Stanisławów. Her father - Edward Zacharski, was railway officer and later also a director of the Stanisławowska Land Bank. Her younger brother Mieczyslaw died in the September Campaign, near Lwów, after Soviet Empire invaded Poland in 1939. Mother, Stanisława Zacharska nee Styczyńska (1881-1963), came from the lesser nobility and never worked professionally. She ran home and raised the children. Stefania Zacharska had two sisters who also reached the centenarian status and died at the ages of 102 and 100.