The new 19th district includes the south side of San Jose and the entire cities of Santa Cruz, Monterey, Seaside, Paso Robles, and Atascadero.

For much of the 20th century prior to the early 1990s, the district had encompassed areas to the south and much of Los Angeles County, California.

The 19th and 16th are partitioned by Old Santa Cruz Highway, Aldercroft Hts Rd, Weaver Rd, Soda Springs Rd, Love Harris Rd, Pheasant Creek, Guadalupe Creek, Guadalupe Mines Rd, Oak Canyon Dr, Coleman Rd, Meridian Ave, Highway G8, Guadalupe River, W Capitol Expressway, Senter Rd, Sylvandale Ave, Yerba Buena Rd, Silver Creek Rd, and E Capitol Expressway.

The 19th and 18th are partitioned by Pajaro River, Highway 129, W Beach St, Lee Rd, Highway 1, Harkins Slough Rd, Harkins Slough, Old Adobe Rd, Corralitos Creek, Varin Rd, Pioneer Rd, Green Valley Rd, Casserly Rd, Mt Madonna Rd.

The 19th district takes in a small section of the city of Watsonville, the cities of Santa Cruz, Scotts Valley, and Capitola, and the census designated places Boulder Creek, Brookdale, Lompico, Zayante, Davenport, Bonny Doon, Felton, Ben Lomond, Mount Hermon, Paradise Park, Pasatiempo, Twin Lakes, Live Oak, Pleasure Point, Soquel, Day Valley, Aptos, Seacliff, Rio del Mar, Corralitos, Aptos Hills-Larkin Valley, La Selva Beach, and Pajaro Dunes.