Castaic's housing is anchored by newer master-planned neighborhoods built as the community grew along the I-5 corridor, alongside established areas closer to the lake and the valley floor. Single-family homes dominate, with a supply of townhomes and larger hillside and foothill properties near the reservoir and the national forest boundary. The community's distance from central Los Angeles and its lake-and-foothills setting give it a more open, spacious character than many parts of the county.

Castaic is organized around the I-5 and State Route 126 corridors and the lake that anchors its northern end. Newer residential developments cluster near the freeway interchanges and along the valley floor, while foothill and hillside areas offer larger lots and views of the lake and the Angeles National Forest. The community's neighborhoods range from compact planned tracts to more spacious, semi-rural properties, all within a short drive of Santa Clarita's commercial centers.

Life in Castaic blends suburban convenience with outdoor recreation. Castaic Lake is the defining amenity, drawing boaters, anglers, and families to its shores, while the surrounding foothills and the Angeles National Forest provide trails and open space. Daily shopping, dining, and services are a short drive away in Santa Clarita, and the community's freeway position keeps the wider Los Angeles region accessible. The pace is quieter than in the city, with a strong orientation toward the outdoors.

Students in Castaic attend the Castaic Union School District, which serves the community through eighth grade with a small network of elementary and middle schools. High school students continue to nearby schools in the surrounding area. The district's community scale and the area's residential growth make schools a central part of Castaic life, and families moving to the area generally enroll through the Castaic Union system for the elementary and middle years.

Castaic sits at the junction of Interstate 5 and State Route 126, one of the most heavily traveled corridors in the state. Interstate 5 connects the community south to Santa Clarita, the San Fernando Valley, and Los Angeles, and north over the Grapevine toward the Central Valley. State Route 126 runs west toward Ventura County. Metrolink commuter rail is available in nearby Santa Clarita, and the freeway network makes Castaic a practical base for commuters.

Castaic Lake State Recreation Area is the heart of local recreation, offering two lakes — the upper lake for sailing, power boating, and fishing, and the lower lake for non-motorized boating and seasonal swimming — along with hiking, biking, picnic areas, and playgrounds. The lake is stocked with bass, trout, and catfish. Beyond the lake, the Angeles National Forest and surrounding foothills provide trails and open space, and the community's northern location opens up access to the region's broader outdoor destinations.