The 25% tariff that landed on March 4 lasted less than 48 hours in its original form. By March 6, after intense lobbying from US automakers and Canadian provinces, Trump amended the executive order to exempt USMCA-compliant goods until April 2. That single amendment changed the calculus for roughly half of all Canada-US truck freight overnight.
Two weeks in, here is what the carve-out actually does, what it doesn't, and how Canadian carriers and shippers should be using the documentation window.
The March 6 Amendment: What Trump Signed
On March 6, 2025, Trump signed an executive order amending the IEEPA tariff he had imposed two days earlier. The amendment exempted goods that qualify under the United States-Mexico-Canada Agreement (USMCA, known in Canada as CUSMA) from the 25% tariff, with the exemption set to expire on April 2.
For potash, a separate carve-out reduced the duty to 10% rather than full exemption. For energy products, the original 10% rate continues to apply. Reuters reported that the practical effect was to exempt an estimated 38% of imports from Canada and 50% from Mexico.
The amendment was almost certainly the result of pressure from Detroit. Reporting at the time traced the lobbying to Ford, GM and Stellantis, all of whom warned that integrated North American auto production would seize up within days under a non-exempt tariff.
What CUSMA Compliance Actually Means
CUSMA-compliant means that a good meets the rules of origin specified in the agreement: typically a regional value content threshold, with certain products subject to specific tariff shift rules. For a good to qualify, it must originate in Canada, the US or Mexico under the agreement's definitions, and the importer must be able to certify that origin on demand.
For trucking, three product categories make up the bulk of qualifying volume: vehicles and auto parts, agricultural products, and chemicals/plastics. The Canadian Trucking Alliance noted that the carve-out covers most of the cross-border lane volume Canadian carriers run, which is why border wait times settled within a week of the amendment.
What the Carve-Out Doesn't Cover
The exemption is significant, but it is not a return to pre-March 4 conditions. Several categories remain subject to tariff.
Steel and aluminum are subject to the separate Section 232 tariff that took effect March 12, regardless of CUSMA status. A Canadian steel coil is tariffed even if it qualifies under CUSMA.
Energy remains tariffed at 10%, including oil and natural gas. CUSMA does not save energy exporters from this duty.
Goods that fail rules of origin testing, even if shipped from Canada, do not qualify. A product assembled in Ontario from primarily Chinese components, for example, may not meet regional value content thresholds and would be subject to the 25% tariff.
Goods imported without proper origin certification are treated as non-compliant by default at the border. The exemption requires documentation, not just origin.
The Documentation That Saves You Money
The technical mechanism for claiming the carve-out is straightforward but unforgiving. The importer of record must claim CUSMA preference at the time of entry, supported by a valid certificate of origin from the producer or exporter. The certificate can be a stand-alone document or integrated into the commercial invoice.
"Every load that crosses without origin documentation is currently moving at full tariff rates. The carve-out exists, but you have to prove you qualify. CBP is not going to give you the benefit of the doubt." - Customs broker, Canadian regional fleet
Three documentation pieces are required for clean entry under the carve-out: a CUSMA Certificate of Origin (or equivalent statement on the commercial invoice), supporting bill of materials documentation showing regional value content, and an HS classification confirmed against current rules of origin schedules.
Why April 2 Is the Next Cliff
The CUSMA carve-out is not permanent. Trump's amendment set an April 2 expiration date, deliberately aligned with the broader "reciprocal tariff" announcement scheduled for the same day. CBC's coverage of the deadline noted that Canadian and Mexican officials are operating under the assumption that a fresh tariff regime will land on April 2, with the structure unknown until that morning.
The shape of post-April 2 rules is unclear. Possibilities include extension of the carve-out, narrowing it to specific industries, replacing it with country-specific reciprocal rates, or layering new tariffs on top of the existing IEEPA framework. None of these can be ruled out.
A Two-Week CUSMA Compliance Playbook
Audit Every Cross-Border SKU This Week
Pull a list of every product you ship cross-border. Confirm CUSMA eligibility for each. The carriers and shippers who do this audit before April 2 will have a procurement advantage no matter what comes next.
Standardize Your Origin Certificates
If you have not been issuing origin certificates with every cross-border invoice, start now. The format is flexible but the substance must include producer, exporter, importer, HS code, origin criterion and regional value content.
Build a Backup Plan for Non-Compliant SKUs
For products that fail CUSMA rules of origin, model the cost impact of full 25% duty. Identify which products can be reformulated to meet rules of origin, and which are economic dead-ends under the new regime.
Talk to Your Broker Twice a Week
Customs broker capacity is tight right now. Broker offices that pre-clear paperwork for known shippers will get loads across faster. Build the relationship before April 2.
Watch Steel and Aluminum Separately
Section 232 is independent of CUSMA. Steel and aluminum shippers should plan for that tariff to remain in place even if CUSMA carve-outs are extended.
Keylink runs Canada-USA full truckload lanes for shippers who can't afford to learn what CUSMA-compliant means at the border. We document every load, every time.
Talk to Our Team →The Bottom Line
The CUSMA carve-out is the most important piece of relief Canadian cross-border freight has received since the tariff regime began. It is also conditional, narrow, and on a tight clock. Two weeks in, the lanes that prepared their paperwork are running. The lanes that didn't are paying full duty or sitting at the border.
By April 2, the picture changes again. Shippers and carriers should be operating under the assumption that the carve-out is the floor, not the ceiling, and that whatever lands on April 2 will reward those who got their CUSMA documentation in order during this window.
At Keylink, we are running every cross-border load with full origin documentation, partnered with brokers who pre-clear our paperwork, and we are talking to our shippers about CUSMA compliance as a standing weekly conversation. The carve-out doesn't help anyone who can't prove eligibility. We make sure ours can.
