A small section of the suburb which is located south of the Hills Motorway-Windsor Road intersection is part of the City of Parramatta.

The best-known Aboriginal person from that time is Pemulwuy, a Bidjigal leader who led the Indigenous resistance movement against the British forces, including sacking farms in Castle Hill, before his eventual capture and execution by the British militia.

The first European settler in the Baulkham Hills Shire was William Joyce, who arrived in Australia in October 1791.

[5] The suburb was largely made up of land grants until the mid 19th century, when many of these started to be subdivided into farms.

[8] This area contained the commercial district of Norwest Business Park, which is no longer within Baulkham Hills.

The most common countries of birth were China 8.2%, India 7.5%, England 2.3%, South Korea 2.1% and Sri Lanka 1.7%.

Other languages spoken at home included Mandarin 10.2%, Cantonese 4.2%, Hindi 3.2%, Korean 2.8% and Tamil 2.1%.

The fastest route from the Sydney CBD is via the M2 Hills Motorway, exiting at Windsor Road.

Baulkham Hills has some 15 places of worship belonging to various Christian denominations including: A Baha'i Spiritual Assembly is also located in the suburb.

The regions community radio station, Alive 90.5, broadcasts from studios and a transmission tower in the suburb.

It has featured high-profile Australian music acts such as Gerling, Something With Numbers, Parkway Drive, and The Getaway Plan.