Northbridge is a suburb on the Lower North Shore of Sydney, New South Wales, Australia. It is located 6 kilometres north of the Sydney Central Business District, in the local government area of the City of Willoughby. Northbridge is a leafy suburb, set in surroundings of bush bounded by the eastern waterways of The Outpost, located within proximity of Middle Harbour. Northbridge is an affluent suburb, ranking in the top 10 postcodes in Australia by average taxable income.