IRP Apportionment

Definition

IRP apportionment is the calculation by which IRP fee revenue is divided across member jurisdictions based on the percentage of total fleet miles operated in each. The base jurisdiction collects the full annual fee from the carrier, then redistributes the proportional share to each other IRP jurisdiction. Apportionment uses the prior-year mileage report as the basis (with a special "estimated mileage" formula for first-year carriers). Carriers that operate exclusively in one state can register in that state under their own non-IRP system; only multi-state operators need apportioned plates. Mid-year jurisdiction additions trigger supplemental apportionment recalculation through the base jurisdiction's IRP module.