UAN is a corrosive liquid that requires stainless steel or fiberglass-lined tankers, ISO tanks, or dedicated liquid fertilizer vessels. Port terminals must have compatible liquid fertilizer receiving infrastructure, and inland distribution depends on pipeline, barge, or specialized tank truck networks. These infrastructure requirements concentrate import entry points at a limited number of Gulf Coast and river terminals, which can create supply-chain bottlenecks during peak spring application seasons.

All standard UAN grades — whether 28%, 30%, or 32% nitrogen — fall within the same SITC heading as urea-ammonium nitrate mixtures in aqueous solution. At the HTS level, classification is not split by nitrogen concentration, but antidumping duty scope rulings may specify concentration ranges or exclude certain grades. Importers should review the scope language of any active order carefully to determine whether their specific UAN grade is covered.