The International Fuel Trade Agreement (IFTA) is an agreement between states and Canadian provinces which allows a carrier to register and pay motor fuel road tax to all participating states and provinces they travel in through the carrier's home or base state. If the carrier is based in Virginia, they will file one tax return every quarter with the Virginia DMV for the total tax or refund due for all IFTA jurisdictions. DMV will report the carrier’s operations to those IFTA jurisdictions for them.
For processing information see the IFTA Procedure Guide or VLIC-6.005
The International Registration Plan (IRP) is a registration reciprocity agreement among states of the United States and provinces of Canada providing for payment of license fees on the basis of total distance operated in all jurisdictions.
The unique feature of this Plan is that, even though license fees are paid to the various jurisdictions in which fleet vehicles are operated, only one license plate and one cab card is issued for each fleet vehicle when registered under the Plan. A fleet vehicle is known as an apportionable vehicle and such vehicle, so far as registration is concerned, may be operated both inter-jurisdictional and intra-jurisdictional.
For more information see the IRP Manual.