Cross-border freight needs three things domestic freight does not: a customs broker, a commercial invoice that accurately describes and values the goods, and a carrier arrangement for the border. Canada shipments usually stay on one truck. Mexico shipments either transload at the border or run through on one trailer with a change of tractor.
Documents you will need
- Commercial invoice with description, value, quantity and country of origin
- Packing list
- Bill of lading
- USMCA certification of origin, if you are claiming duty-free treatment
- Any permits your commodity requires
Mexico: transload or through-trailer
In a transload, freight is moved from the U.S. trailer to a Mexican carrier's trailer at a border warehouse. It is common and economical, but adds handling.
In through-trailer service, the same trailer crosses and a Mexican tractor takes over. It reduces handling and suits fragile or high-value freight.
Canada: pre-arrival clearance
Carriers send shipment data to customs before the truck reaches the border, and the customs broker submits the entry against it. When the paperwork is filed ahead of arrival, a truck normally clears in minutes.
What causes delays
- Vague commodity descriptions on the invoice
- Values that do not match the purchase order
- No broker named before pickup
- Missing permits for regulated goods such as food, chemicals or wood products
Common questions
Do I need a customs broker?
Yes, for commercial shipments. The importer of record needs a licensed broker in the destination country to file the entry. Mexico exports also need a Mexican broker.
Can LTL ship across the border?
Yes. Both LTL and truckload move between the United States, Canada and Mexico, including refrigerated and flatbed freight.
Written by the MeritSpan Logistics team. Last reviewed November 9, 2026. Figures are typical values; equipment and carrier rules vary.