The club was formed in 2000 when it joined the National Soccer League (NSL) as Newcastle United, and was one of only three former NSL clubs to become founder members of the A-League.

Newcastle United was formed in 2000 by Cypriot-Australian businessman Con Constantine from the remnants of the Newcastle Breakers club. The Breakers were dissolved when Soccer Australia revoked its NSL license at the conclusion of the 1999/2000 season. At the formation of Newcastle United the home ground was moved back to where Newcastle KB United played, now known as EnergyAustralia Stadium. The Newcastle United club were reasonably successful, competing in two of the last three Final Series snf finishing 2nd in the League behind Perth Glory in the 2001-02 season. The clubs colours were Blue and Red, somewhat traditional colours of the region also worn by the Newcastle Knights Rugby League team.

Newcastle United was renamed as Newcastle United Jets when it joined the A-League in its inaugral 2005-06 season. The club was renamed to project a new image and to prevent confusion with the English Premier League club Newcastle United F.C. The name "Jets" is a reference to RAAF Base Williamtown, located just 20 kilometres north of Newcastle. The club's logo depicts three F/A-18 Hornets, which the Royal Australian Air Force has based at Williamtown.

The Club has been relatively successful throughout the first 3 seasons of the A-League finishing 4th and 3rd in successive seasons and eventually winning the Grand Final in 2007-08 after finishing 2nd in the regular season.