Quarterly fuel-tax reporting across the states and provinces you drove in.
Applies to qualifying vehicles running in more than one jurisdiction. You report miles by state and fuel bought by state, and settle the difference each quarter through your base jurisdiction.
It is arithmetic, not judgement, which is why it is such a waste of an operator's weekend. Getting it wrong invites an audit; getting it late invites a penalty.
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Inteleri works out what a load actually pays you once things like this land. See how it works.