Description: This layer shows all incorporated and unincorporated areas of Los Angeles County. The incorporated city boundaries are maintained by the Department of Public Works as part of the cadastral landbase, and reflects the most current annexations as of the date listed below. The unincorporated areas are maintained by the Department of Regional Planning for land use planning efforts. This version was updated October 20, 2025 to fix an underlying issue with Esri.This layer was updated on 7/28/22 to match a major city boundary update from Public Works (see update history below). A hosted feature layer is located here.UPDATE HISTORY (beginning 2015)1/5/15 - Re-organization between Torrance and Rolling Hills Estates4/22/15 - Annexation to Los Angeles from Florence-Firestone (Jordan Downs)6/9/15 - updated 'Adopted Date' for Santa Clarita Valley (wasn't done before!)6/17/15 - following the adoption of the Antelope Valley Area Plan update, the boundary between Santa Clarita Valley and AV was updated, as well as the boundary between Kagel / Lopez Canyons and Antelope Valley.8/31/15 - updated Universal City for Reorganization 2014-01.11/5/15 - updated following the General Plan 2035 going into effect. Boundary change for Kagel / Lopez Canyons, South San Gabriel / Whittier Narrows, and added boundary for Pepperdine University.3/17/16 - following an Assessor adjustment of parcel #3022012017, city boundary between Palmdale and AV was adjusted. Informed DPW as well.4/21/16 - updated San Clemente Island to match what DPW had (compared to imagery, ours was shifted). Also a re-organization between the cities of Rolling Hills Estates, Rolling Hills, and Rancho Palos Verdes. Links to both are here (document 1, document 2).11/15/16 - Updated for annexation to Santa Clarita that became effective on this day (link to official annexation document is here). Also, updates that resulted from a comprehensive city boundary update after comparison with Public Works' city boundary layer.4/19/17 - Updated for reorganization between the cities of Pomona and Diamond Bar (click here).2/5/18 - Updated for reorganization between the cities of Monrovia and Bradbury (click here).11/20/18 - Updated for RPPL 2017005805 (adopted 10/30/18) for re-alignments between the unincorporated communities of Santa Clarita Valley and Antelope Valley (for plan amendment, click here).11/21/18 - updated for Plum Canyon / Skyline Ranch / North Sand Canyon Annexation. This annexation was effective on 11/15/18, and a link to the official LAFCO annexation document is here.1/29/19 - updated for South Walnut / Pomona annexation, which was effective on 1/16/19. A link to the official LAFCO annexation document is here.5/28/19 - updated for detachment from city of Los Angeles to Del Aire. Effective 5/16/19, and a link to the official LAFCO annexation document is here.7/25/19 - updated for annexation and detachment from the city of Arcadia to South Monrovia Islands and East Pasadena-East San Gabriel, respectively. Effective 6/13/19, and a link to the official LAFCO annexation document is here.1/28/21 - updated a couple errors in the data - Date Adopted for the Florence-Firestone Community Plan, and updated Type for Walnut Park to 'NEIGH' (character length limit).1/26/22 - updated the Twin Lakes / Oat Mountain community boundary through zoning conflation project. This is to follow the updated parcels along the southern Twin Lakes border.4/12/22 - updated Gilmore Island as it was found to be 5 feet too wide on the easterly boundary. Consulted with Assessor and Public Works for confirmation.5/23/22 - updated the boundary between Twin Lakes and Oat Mountain to account for a parcel shift as identified by the Zoning Conflation project.7/28/22 - major update to all city boundaries in the entire county based on an update from Public Works. Several city boundaries were updated to follow parcels, with the majority of changes being slivers, or very minor shifts. The coastline was the major adjustment and used the latest data from NOAA.8/17/22 - boundary adjustment between Industry and North Whittier per DPW update (APN 8125021943).12/20/22 - updated for Reorganization (Tesoro Del Valle) between Santa Clarita and Santa Clarita Valley. Effective on 11/14/22.4/10/23 - fixed a slight discrepancy on APN 7351036014 in West Carson (city boundary cut through this parcel) - confirmed with DPW on this date.4/1/24 - Updated the community of View Park official name - we had as 'Ladera Heights / Viewpark - Windsor Hills' now correctly shown as 'Ladera Heights / View Park - Windsor Hills'.4/14/24 - Updated for the annexation to the City of La Verne that was effective on 3/31/24. Annexation document is here.6/20/24 - Updated with three new unincorporated communities resulting from the East San Gabriel Valley Area Plan update.12/11/24 - Updated to an annexation to the City of Whittier that was effective on 11/12/24. Annexation document is here.3/19/25 - Updated for annexation to the city of Duarte (removal of northernmost South Monrovia Islands community). Annexation was effective on 3/17/25.3/20/25 - Updated for a boundary adjustment between Arcadia and Monrovia (APN: 5780-019-011).4/9/25 - Updated communities resulting from the update of the South Bay Area Plan, and the Westside Area Plan (splitting Del Aire into Del Aire and Wiseburn); renaming 'Alondra Park' to 'Alondra Park / El Camino Village', 'Westfield' to 'Westfield / Academy Hills', and 'West Fox Hills' to 'Del Rey'.9/1/25 - Updated for annexation to the City of San Gabriel, from the unincorporated community of East Pasadena - East San Gabriel. APN: 5374027005
Service Item Id: 5e4c11dfa88a41cbbf6f6d06d7bdc517
Copyright Text: County of Los Angeles
Department of Regional Planning, Department of Public Works, Assessor's Office