Seven Hills was established for the first time in 1981 but it was abolished in 1991. It was recreated from 2015 as a result of the 2013 redistribution.[2] It is named after and including the Sydney suburb of Seven Hills.
The second incarnation of Seven Hills largely consisted of areas from the abolished seat of Toongabbie, which had historically been a Labor stronghold before Labor's near-meltdown in west Sydney in the 2011 election. In the election, the Labor margin was reduced from a comfortably safe 14.5 percent to an extremely marginal 0.3 percent. The transfer of traditionally pro-Labor voting areas to Blacktown and Prospect, and the addition of equally pro-Liberal areas from Baulkham Hills significantly altered the political composition of the electorate, giving the Liberals a notional margin of 8.8 percent–on the stronger side of fairly safe. The sitting member for Toongabbie was former Labor PremierNathan Rees, who concluded the new Seven Hills was impossible to hold and retired at the 2015 election.[3][4]
As a result of a redistribution in 2021, Seven Hills will be abolished at the 2023 election and largely replaced by Winston Hills.[5]