The one break in this tradition came in the "Wranslide" of 1978, when a split in the Liberal vote allowed Labor's Eddie Britt to sweep into office.
However, a redistribution ahead of the 1981 election erased Britt's majority and made Willoughby notionally Liberal.
Britt narrowly lost to future state opposition leader Peter Collins even in the face of the second "Wranslide.
Pat Reilly, the longtime mayor of the City of Willoughby, ran as an independent and nearly defeated Liberal Gladys Berejiklian on Labor preferences.
Both Premiers (Sir) Charles Wade and Gladys Berejiklian held Willoughby while in office, the other three electorates being Ku-ring-gai, Maroubra and Wollondilly.