909 Area Code – San Bernardino, California: Location, Time Zone & History

The Inland Empire's 909 was carved out of area code 714 on November 14, 1992, taking eastern Los Angeles County and the growing southwestern San Bernardino and western Riverside county corridor, with mandatory dialing beginning in August 1993. Continued growth in Riverside County led to another split on July 17, 2004, when area code 951 took over that western territory, leaving 909 focused on southwestern San Bernardino County and the eastern San Gabriel Valley.

Rather than split again, the California Public Utilities Commission approved 840 as an all-services overlay of 909 in 2019. Mandatory ten-digit dialing took effect January 23, 2021, and 840 numbers began issuing a month later, on February 23, 2021 -- 909's first overlay after nearly three decades serving the Inland Empire alone.

The 909/840 complex anchors one of the largest logistics and warehousing hubs in the country, built around Ontario International Airport and the distribution corridors of Ontario, Fontana, and Rancho Cucamonga that feed the ports of Los Angeles and Long Beach. Historic Route 66 still runs through the San Bernardino-Rialto-Fontana corridor, and the region is home to Cal Poly Pomona, Cal State San Bernardino, and the Claremont Colleges. Pomona itself is split between the 909/840 overlay and neighboring 626.