On September 8, 2026, the President signed five proclamations under Section 338 of the Tariff Act of 1930. Three of them convert a tariff into a prohibition: certain Canadian alcoholic beverages, dairy products, and motor vehicle products are excluded from importation into the United States effective 12:01 a.m. eastern time on September 29, 2026. The other two change which Canadian products carry the existing 50 percent Section 338 duty, effective 12:01 a.m. eastern time on September 15, 2026.
If you import covered Canadian goods, that is six days until the scope change and twenty days until the exclusion, counting from today, September 9, 2026. This piece explains what the proclamations say, what they do not say, and which of the two dates is the one that should be driving your decisions this week.
What the President signed on September 8
The White House fact sheet describes the trigger plainly: after breaking off trade negotiations, Canada imposed new retaliatory tariffs on about $20 billion of U.S. exports, including steel, dairy, and agricultural equipment. The five proclamations are the response, and they split into two groups that do fundamentally different things.
Three exclusion proclamations. One each for alcoholic beverages, dairy, and motor vehicles. Their titles all use the same construction — "Excluding Certain Canadian Products from Importation into the United States in Response to Continued Discrimination Against the Commerce of the United States." These exclude from importation certain Canadian products that were previously subject to the 50 percent Section 338 duties imposed by Proclamations 11046, 11047, and 11048 of July 20, 2026. The motor vehicles proclamation states it is "effective with respect to goods imported on or after 12:01 a.m. eastern time on September 29, 2026."
Two scope-modification proclamations. One for motor vehicles and one for alcoholic beverages, both titled "Modifying the Scope of Products of Canada Subject to the Additional Duties." These take effect at 12:01 a.m. eastern time on September 15, 2026. Annex I, Part A adds products to the 50 percent duty; Annex I, Part B removes products from it; Annex II carries the corresponding modifications to the Harmonized Tariff Schedule of the United States (HTSUS — the classification schedule that determines duty rates and reporting requirements). Per the fact sheet, the additions include all-terrain vehicles (ATVs) and additional dairy products, and the removals include rock salt and cement.
The legal authorities cited in the motor vehicles proclamations are Section 338 of the Tariff Act of 1930 (19 U.S.C. 1338), Section 604 of the Trade Act of 1974 (19 U.S.C. 2483, the President's authority to modify the HTSUS), and Section 301 of Title 3, United States Code. Section 338 is the statute that lets the President impose additional duties on the products of a country that discriminates against U.S. commerce — and, where that discrimination is maintained or increased, exclude that country's articles from importation altogether.
This is the same statutory line that produced the duties now in force. We covered the entry-summary mechanics of that first action in Section 338 on Canadian goods is live: Proclamation 11056, signed August 18 and published August 24, 2026 at 91 FR 54789, set the effective date of the 50 percent duties at 12:01 a.m. eastern time on August 22, 2026 after a three-day suspension.
Why "excluded from importation" is a different animal than 50 percent
An importer who has spent 2026 absorbing tariff after tariff has built a set of reflexes: model the landed cost, decide whether the margin survives, reprice or resource, and file the entry. Every one of those reflexes assumes there is a number you can pay to get your goods across the line. That assumption is what an exclusion breaks.
A duty is a price. A ban is a door. Under an exclusion proclamation, there is no rate, no Chapter 99 heading you can report to make the shipment admissible, and no version of the entry that clears. You cannot buy your way in at 60 percent instead of 50. If your product is on the annex list and it is imported on or after the effective moment, the transaction does not have a compliant path — it has a different plan, or it does not happen.
That distinction changes who inside your company needs to be in the room. A 50 percent duty is a finance conversation. An exclusion is a sourcing, contracting, and customer-commitment conversation, and it needs to start before September 29 rather than after a container is sitting somewhere it cannot clear. If you have purchase orders, seasonal allocations, or customer contracts written against Canadian-origin goods in these three categories, the exposure is not a cost line — it is a delivery you may not be able to make.
The in-transit rule is the sentence to read twice
Here is the operative language from the motor vehicles exclusion proclamation, verbatim:
"Products that will be subject to the import ban in this proclamation that were imported, but not yet entered for consumption, or withdrawn from warehouse for consumption, prior to September 29, 2026, will remain subject to the 50 percent duty rate established by Proclamation 11048."
Read it slowly, because the pivot is not where most people expect it. The effective clause attaches to importation — goods imported on or after 12:01 a.m. eastern time on September 29. And the sentence above says that goods which were already imported before that moment, but had not yet been entered for consumption or withdrawn from warehouse for consumption, stay under the 50 percent duty rather than falling under the exclusion.
So the question that determines your outcome on a given shipment is not only "when did I file?" It is "when was this merchandise imported?" A shipment that arrives before September 29 and gets entered on October 3 reads, on the face of this text, as dutiable at 50 percent rather than barred. A shipment that arrives on October 3 reads as excluded, regardless of how ready your entry paperwork was.
Two things follow, and both matter operationally.
First, arrival timing and warehouse strategy suddenly carry the same weight that classification and valuation normally do. Goods sitting in a bonded warehouse were imported when they arrived, which on this text means a later withdrawal for consumption is a 50 percent event and not a prohibited one. That is a meaningful position for anyone already holding inventory in a warehouse or considering whether to route arriving goods into one.
Second, "imported" is not defined in the proclamation text we read, and the mechanics of how CBP will validate an importation date in the Automated Commercial Environment (ACE — the system all electronic entries flow through) have not been published. That is exactly the kind of detail that a CSMS message (Cargo Systems Messaging Service, CBP's official trade bulletin channel) normally resolves, and none had issued as of September 9, 2026. Document arrival dates now — bills of lading, arrival notices, in-bond records, warehouse admission records — so that whatever proof CBP eventually asks for, you already have it in the file rather than reconstructing it in November.
We are describing the rule as written and stopping there. We are not telling you to rush cargo across the border, and we are not predicting how CBP will interpret or enforce any of it.
The September 15 scope change cuts both ways
The scope proclamations create two entirely different problems six days from now, and importers tend to only notice the one that costs them money.
If your product was just added. ATVs and additional dairy products move onto the 50 percent Section 338 duty at 12:01 a.m. eastern time on September 15. If that is you, entries filed on or after that moment need the correct Chapter 99 reporting line and a landed cost that reflects the additional duty. Six days is enough time to update your entry templates and tell your customers, and not much more. Note also that being added to the duty list on September 15 and being excluded from importation on September 29 are separate actions in separate proclamations — do not assume one implies the other for your specific subheading.
If your product was just removed. Rock salt and cement come off the 50 percent duty on the same date. This is the quieter failure mode: nobody chases the money they were never billed, but they very much do keep paying a duty that stopped applying. If your entry templates, broker instructions, or self-filing configuration carry a Section 338 Chapter 99 line for these goods, that line needs to come out for entries on or after September 15. Filing a duty you no longer owe is still a filing error, and it is your error, not CBP's.
If an entry does go out after September 15 with a Chapter 99 line that no longer applies, a post summary correction (PSC — the electronic amendment to a filed entry summary, available before liquidation) is the mechanism for fixing your own filing. Strix files PSCs at $150 per entry for up to 10 lines. What we will not tell you is what CBP will do with it; we file the correction, the agency decides the outcome. Our post summary corrections page walks through the window and the process.
One caution that applies to both directions: the fact sheet names product categories, but the annexes name subheadings, and only the annexes are operative. "We import cement" is not a compliance determination. Pull your own 8-digit HTSUS codes and check them against Annex I, Part A and Part B before you change a single template.
What is not confirmed as of September 9, 2026
This is a fast-moving story, and the honest version of it has holes. Naming them is more useful than papering over them.
No Federal Register publication that we could confirm. As of September 9, 2026, we found no Federal Register text for these five proclamations. Our attempt to search federalregister.gov redirected to an access-control page, so treat this as "not confirmed by us" rather than "confirmed absent." The FR text, when it publishes, is the citable version and may carry annex detail the White House posting does not.
No CBP filing guidance. We found no CSMS message covering these proclamations as of September 9, 2026. That means no published Chapter 99 heading for the scope additions, no published ACE mechanics for the exclusion, and no CBP statement on how the in-transit sentence will be administered. For the earlier round of Section 338 duties, CBP's filing instructions arrived the night before the effective date. Plan for guidance to be late rather than early.
No HTSUS-level product list in this article, on purpose. The operative lists live in annex PDFs on whitehouse.gov, and we could not extract machine-readable text from the Annex I auto PDF this run. We are not going to guess at subheadings or partially list them — a partial list is worse than no list, because it invites someone to conclude they are not covered. Check your own codes against the annexes.
No position on carve-outs. The exclusion proclamation text we read does not state a civil aircraft or General Note 6 carve-out, does not address foreign trade zone (FTZ) treatment, and does not address in-bond movements. We are not asserting that carve-outs exist, and we are not asserting that none do. If your goods touch an FTZ, an in-bond move, or a Chapter 98 provision, that is a question for CBP or your broker against the annex text — not something to infer from a fact sheet.
For how these Section 338 lines interact with the other 2026 remedies already on your entries, our 2026 tariff stacking guide covers the sequencing.
What to do in the next six days
- Pull your Canadian-origin SKU list with 8-digit HTSUS codes. Not descriptions. Codes.
- Check each code against Annex I, Part A and Part B of the September 8 scope proclamations. Additions and removals both need action.
- Check each code against the exclusion annexes for alcoholic beverages, dairy, and motor vehicles.
- Fix your templates before September 15, in both directions — add the Chapter 99 line where it now applies, remove it where it no longer does.
- Inventory what is in transit and what is in a warehouse, with arrival dates documented, so you can apply the in-transit sentence to real shipments rather than to a hypothetical.
- Watch for the CSMS message and the Federal Register text, and re-verify anything in this article against them once they land.
- Talk to the commercial side of your business now if any excluded category is load-bearing in your sourcing. Twenty days is short for a sourcing change and very short for a contract conversation.
No. An exclusion under Section 338 removes the product from importation rather than pricing it. There is no rate to pay and no Chapter 99 heading that makes an excluded article admissible. That is the core difference between these three proclamations and the duty proclamations that preceded them.
My goods arrive before September 29 but I will not file the entry until October. What happens?
The motor vehicles exclusion proclamation states that products subject to the ban that were imported, but not yet entered for consumption or withdrawn from warehouse for consumption, prior to September 29, 2026, remain subject to the 50 percent duty rate established by Proclamation 11048. On that text, the importation date is the pivot. CBP had not published filing guidance as of September 9, 2026, so keep your arrival documentation and confirm the mechanics against the CSMS message when it issues.
My product is coming off the duty list on September 15. Do I get money back on entries I already filed?
The scope modification takes effect at 12:01 a.m. eastern time on September 15, 2026 — it is a forward-looking change to what is subject to the duty, not a refund program, and none of the five proclamations we read establishes one. What is squarely in your control is not overpaying going forward: get the Chapter 99 line off your entries for goods entered on or after September 15. If a post-September 15 entry goes out with the line still on it, a PSC is the tool for correcting your filing. We do not predict CBP outcomes.
How do I know whether my specific product is covered?
By subheading, from the annexes — not from the product-category names in the fact sheet or in this article. The operative lists are the annex PDFs attached to the proclamations, and CBP's forthcoming guidance will map them to reportable Chapter 99 headings. If your 8-digit code is not clearly on or off a list, that is a question to resolve before September 15, not after an entry rejects.
Where we can help
Two dates, both close. Six days to a scope change that adds duty for some importers and removes it for others, and twenty days to an exclusion that no amount of duty will get you past.
We can clear entries for Canadian-origin goods with the Chapter 99 lines CBP publishes, consult on how the in-transit sentence and the annex lists apply to your specific subheadings and shipments, comply by getting your entry summaries and PSCs right in both directions after September 15, and automate the template and validation changes so a removed duty line does not keep riding on your entries for another quarter. Self-filing runs $30 per entry, brokerage $100–$250 per entry, and PSCs $150 per entry for up to 10 lines. CBP decides admissibility and rates; we handle the filing.
If you import Canadian alcoholic beverages, dairy, motor vehicle products, ATVs, rock salt, or cement, talk to our team this week. If you would rather have a licensed broker on the entry itself, start at brokerage.
This article states the position as of September 9, 2026, one day after the proclamations were signed and before Federal Register publication or CBP filing guidance was available to us. Verify against the Federal Register text and the CSMS message before acting.