Calabasas is a city in Los Angeles County, California, in the western United States. As of the 2005 census, the city population was 23,123. The city was formally incorporated in 1991. Many parts of Calabasas are mountains or hills, which have spectacular views of the San Fernando Valley. Many of the neighborhoods in Calabasas are gated communities; with homes ranging is size from approximately 1,500 sq ft to 15,000 sq ft.

The city is located at the southwestern edge of the San Fernando Valley and comprises a portion of the Santa Monica Mountains. It is bordered by the Woodland Hills area of Los Angeles to the northeast, Topanga to the southeast, Malibu to the south, Agoura Hills to the west, and Hidden Hills to the north. The historic El Camino Real runs east-west through Calabasas as U.S. Route 101. Calabasas is in relatively close proximity to some of the most popular destinations in Los Angeles; Malibu – 12 miles, Beverly Hills – 22 miles, Downtown Los Angeles – 27 miles.

Calabasas funds its own public transportation in the form of shuttle and trolley service and funds its own library (as opposed to using the County library system), runs its own tennis and swimming center, has a protected and maintained historical district, has its own television channel called "The Calabasas Channel", and has four car dealerships along Calabasas Road. While Calabasas is oftentimes considered similar to its neighboring two cities to the west (Agoura Hills and Westlake Village, which is a trio that can be compared to the Burbank-Glendale-Pasadena area) because of similar demographics, size (physically and population, save Westlake), geography, and low-density general plans, Calabasas is unique from these two for the above things as the two other cities have none of the above features.