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Area codes 909 and 840 are telephone area codes in the North American Numbering Plan for the far-eastern part of Los Angeles County, southwestern San Bernardino County, and a small portion of Riverside County in the U.S. state of California. Area code 909 was created on November 14, 1992, in an area code split of 714 and 840 was added to the numbering…
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area 909 code split numbering plan county riverside california overlay 714 951 codes north american 840 san corona los angeles
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