Arizona cannot be your UCR base state, and the Plan names the ten that can
The participating-states list is the starting point and it is short work to check. Read at the source on September 3, 2026, it names Alabama, Alaska, Arkansas, California, Colorado, Connecticut, Delaware, Georgia, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, New Hampshire, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, Washington, West Virginia and Wisconsin. Forty-one entries, and no Arizona.
The consequence is set out in the Plan’s own FAQ, under the question “What is a UCR registrant’s base state under the UCR Agreement?”. The answer opens by describing the structure: “The UCR Agreement is a base-state system, under which a UCR registrant pays UCR fees through its Base State on behalf of all the participating States.” It then runs a hierarchy, and Arizona appears by name in the fourth limb of it.
The sentence that governs an Arizona operator reads: “If your principal place of business state is AZ, HI, NV, OR, or WY, or the Canadian Province of AB, BC, MB, NT, NU, SK or YT or a state of Mexico, you may select one of the following states: AK, CA, CO, ID, MT, ND, NM, SD, UT, or WA.” Note the verb. For a carrier based in a participating state the Plan says “you must use that state as your base state”; for an Arizona carrier it says “you may select”. Arizona is one of five states whose operators are given a genuine choice.
The obvious next question is whether the choice is worth optimizing, and the Plan answers it directly in the same document: “Neither will it matter under the UCR Agreement, which State is acting as a carrier’s Base State – the level of UCR fees for a fleet of a given size will stay the same.” So the ten states named above are ten routes to an identical outcome. A new venture should pick on convenience and on nothing else.
Two limits on this are worth stating rather than leaving implicit. UCR reaches interstate and international operation; a carrier whose trucks never leave Arizona is outside the Agreement entirely and has no base state to select. And the absence of Arizona from the participating list is a fact about who collects and administers the fee, not a discount — the schedule set out above this section is the schedule an Arizona-based carrier pays through whichever of the ten states it selects.
- Read at the source September 3, 2026: the UCR Plan participating-states list carries forty-one states and Arizona is absent from it.
- UCR Plan FAQ, quoted verbatim: an operator whose principal place of business is in AZ “may select one of the following states: AK, CA, CO, ID, MT, ND, NM, SD, UT, or WA.”
- The same FAQ, on whether the choice changes the price: the fee level “for a fleet of a given size will stay the same.”
- An Arizona carrier that never crosses a state line is outside UCR and selects nothing.