Area Code Atlas
Area codes, places,
and the stories behind them.
Find what place an area code covers, how it split from or overlaps its neighbours, and how it got here — every fact cited.
Explore by place
California
California has more telephone area codes than any other U.S. state — more than 40 active area codes as of 2025...
Metro areaLos Angeles
9 area codes, one shared history.
Area codes
A growing set of profiles — each with the place it covers, its relationships and its history. Not a ranking.
San Gabriel Valley, eastern Los Angeles County, California
Western and southern Los Angeles County (Westside, South Bay, Harbor) and Santa Catalina Island, California
San Fernando Valley and adjacent northern Los Angeles County communities
West Los Angeles, the Westside, the South Bay and L.A. County beach cities (shares 310's geography)
Downtown and central Los Angeles and adjacent southeast L.A. County communities
Central Los Angeles and surrounding southeast L.A. County cities
How Los Angeles's original area code split into today's core codes
A single code — 213 — once served a broad Southern California territory. Follow the 213 lineage of splits and overlays that produced the core Los Angeles County codes, each event dated and cited to CPUC records.
Open the Los Angeles history pack →Compare area codes
Side by side — only facts with a source. No invented "value" scores.
San Gabriel Valley vs West LA & South Bay
Downtown & Central LA vs Central Los Angeles
West LA & South Bay vs West LA / South Bay (overlay)
San Fernando Valley vs San Gabriel Valley
Every page cites its sources and marks its last-verified date — see how this is made. Facts licensed CC BY 4.0. Underlying numbering data: NumberResearch.