Bonsall is a census-designated place (CDP) in San Diego County, California.

The Bonsall area was heavily affected by the Lilac Fire in December 2017, which burned 4,100 acres.

[4] It received a post office in 1881 under the name Osgood, after California Southern Railroad chief engineer Joseph O. Osgood; the renaming was supposedly an unsuccessful attempt to convince Osgood to build the railroad through the San Luis Rey River Valley (the rail line eventually followed the Santa Margarita River instead).

Following a contest, the town was renamed Bonsall in 1890, after local minister James A.

[5] Bonsall is just east of Oceanside and Camp Pendleton, north of Vista and northwest of Hidden Meadows.

According to the United States Census Bureau, the CDP has a total area of 13.6 square miles (35 km2).

The racial makeup of Bonsall was 3,194 (80.2%) White, 67 (1.7%) African American, 28 (0.7%) Native American, 138 (3.5%) Asian, 10 (0.3%) Pacific Islander, 376 (9.4%) from other races, and 169 (4.2%) from two or more races.

There were 1,357 housing units at an average density of 100.7 per square mile (38.9/km2).

In the California State Legislature, Bonsall is in the 38th Senate District, represented by Democrat Catherine Blakespear, and in the 75th Assembly District, represented by Republican Carl DeMaio.

[27] In June 1988, Bonsall-area voters defeated a ballot initiative to create a Community Services District ("CSD") after opponents argued that the boundaries included too many county taxpayers who more closely associated with neighboring cities Vista and Fallbrook rather than the unincorporated Bonsall community.