The arrival of the 840 overlay resolved a critical capacity shortage for the Inland Empire, securing millions of new assignable lines for ongoing industrial and residential growth. As automated devices, internet-connected utilities, and mobile devices continue to proliferate, geographic numbering systems across the United States will increasingly turn to overlays as the default preservation strategy.
For residents and commercial operators throughout San Bernardino County and the Pomona Valley, ten-digit dialing is now second nature. The change altered the simple act of dialing a neighbor, but it preserved the integrity of established regional identities. While the 909 prefix retains its deep cultural roots, it now shares the network with the 840 code, quietly keeping one of California’s most vital economic engines connected.
