The modern drain on telephone prefixes stems from industrial automation rather than traditional home telephone lines. Over the past decade, the Inland Empire transformed into the logistics capital of North America. Massive fulfillment facilities and intermodal transport centers dominate the landscape in Ontario CA, Fontana, and Rancho Cucamonga.
Every commercial vehicle fleet tracking device, cellular-connected security gateway, and automated inventory terminal requires an assignable network identifier. While many enterprise systems utilize private IP structures, vast quantities of commercial IoT hardware remain tethered to traditional SIM profiles requiring NANPA central office allocations. Carriers routinely request blocks of numbers to support enterprise supply-chain accounts situated along the Interstate 10 and Interstate 15 corridors.
To prevent another disruptive split, the CPUC abandoned geographic partitions in favor of overlays and conservation methods. In early 2021, regulators introduced the 840 area code as an overlay on the 909 region. The decision ended traditional seven-digit local calling, mandating ten-digit dialing for all calls within the zone. Crucially, the overlay preserved existing numbers for businesses while allowing new automated endpoints to absorb 840 designations.
