Does the Section 338 tariff apply to my Canadian goods, even with a USMCA claim?

Which Canadian goods carry the Section 338 duty?

Only products of Canada classified in a subheading listed in U.S. note 51(b) to subchapter III of chapter 99. The note has three lists, each tied to one heading, and every heading carries the same rate: "The duty provided in the applicable subheading + 50%."

The provision counts are our count of the subheadings and statistical numbers printed in note 51(b) of Revision 23 of the 2026 Harmonized Tariff Schedule, current on November 11, 2026.

The names describe the Canadian measure each proclamation responds to, not what is on the list. The alcoholic-beverage list also holds cheese, hides and furskins, wood and paper items and boats. The motor-vehicle list is the longest and runs from live plants and cut flowers through cosmetics, paints, plastics, wood, paper, steel and aluminum structures, machinery and furniture. Do not decide coverage by the product's industry. Look up the line's subheading in the list for the entry date.

Why does a USMCA claim not remove it?

Because note 51 says so. Note 51(a) reads: "Products that are eligible for special tariff treatment under general note 3(c)(i) to the tariff schedule, or that are eligible for temporary duty exemptions or reductions under subchapter II to chapter 99, shall be subject to the additional ad valorem rate of duty imposed by these headings, except as otherwise provided in this note." USMCA is one of the programs in general note 3(c)(i), and nothing else in note 51 exempts USMCA goods.

This is the opposite of how the other 2026 actions treated Canada. The IEEPA Canada duty excused goods entered free under USMCA (heading 9903.01.14), the Section 122 surcharge did too (9903.03.07), and the Section 301 forced-labor duty still does (9903.05.93, note 52(g)). Section 338 has no such heading. That is why the claim still matters on a listed line: it removes the base rate and the forced-labor duty, but the 50 percent stays.

What dates decide whether a line was covered?

The duty applies to goods "entered for consumption, or withdrawn from warehouse for consumption" on or after the stated time. The proclamations were signed on July 20, 2026 with a start of August 19. Proclamation 11056 of August 18, 2026 moved the start to 12:01 a.m. eastern time on August 22, 2026, and CBP's CSMS # 69606660 of August 21 implemented that date.

Three later changes matter for an audit:

1. September 15, 2026. Proclamations 11064 and 11065 changed the alcoholic-beverage and motor-vehicle lists, and said those duties "shall apply in addition to duties imposed pursuant to section 232." CBP's CSMS # 69851916 put it plainly: "As of September 15, 2026, only goods subject to HTSUS 9903.03.13 are eligible to claim HTSUS 9903.03.15." Before that date, a Section 232 article on any of the three lists could claim relief; from that date, only a dairy-list article can.
2. October 30, 2026. Proclamation 11076 changed the motor-vehicle list again for goods entered from 12:01 a.m. eastern time October 30, 2026, adding products and removing others (CSMS # 70314289).
3. No in-transit rule. CSMS # 69606660 has no in-transit heading, and note 51 as printed has none, so goods afloat on August 22 or October 30 took the duty that applied on their entry date.

A product's coverage can therefore change between two entries of the same goods. Lip make-up of 3304.10.00 has been on the motor-vehicle list since August 22; steel structures and parts of 7308.90.95 joined it on September 15, and air conditioners of 8415.10.30 on October 30.

What else switches the duty off?

The exceptions are narrow:

• Civil aircraft goods that meet general note 6 and fall in the subheadings listed in note 51(d) go under 9903.03.16 with no Section 338 duty.
• Section 232 articles on the dairy list go under 9903.03.15. From September 15, 2026 this relief covers nothing on the alcoholic-beverage or motor-vehicle lists.
• Chapter 98 entries properly claimed are outside the duty, except subchapter XXIII of chapter 98 and 9802.00.40, 9802.00.50, 9802.00.60 and 9802.00.80, where the duty applies to the value of the repair, processing or foreign assembly (note 51(a)).
• Personal-use goods in accompanied baggage.

Antidumping and countervailing duties continue to apply alongside it, and goods admitted to a foreign-trade zone after the start can only take privileged foreign status (CSMS # 69606660).

Worked 7501 line: Canadian wine entered November 2, 2026

The goods: still wine in containers of 2 liters or less, HTS 2204.21.50, product of Canada, 2,000 liters, entered value $10,000, entry date November 2, 2026. The general rate is 6.3 cents per liter; the special column shows "Free" for program "S" (USMCA). Subheading 2204.21.50 is on the note 51(b)(1) list, so heading 9903.03.12 applies. Canada's forced-labor heading is 9903.05.29 at 10 percent, unless the goods are entered free under USMCA.

The Section 338 duty is ad valorem even where the base rate is specific: the 50 percent is charged on the entered value, while the 6.3 cents applies per liter. CBP's CSMS # 69606660 lists the reporting sequence (Chapter 98, then Chapter 99 numbers for additional duties, then trade remedies starting with Section 301, then the chapter 1 to 97 number with the entered value) but does not name where the Section 338 number sits in it, so check the order your broker's software uses against CBP's message. The money is the same either way.

The audit findings this line can produce:

• A November entry with 9903.05.93 and no 9903.03.12: underpaid $5,000. The USMCA claim was treated as if it removed everything.
• A November entry with 9903.05.29 and a valid USMCA certification on file: overpaid $1,126, the forced-labor duty and the base rate. A post-importation USMCA claim under 19 U.S.C. 1520(d), within a year of importation, recovers both.
• An entry dated August 21 with 9903.03.12 on it: overpaid $5,000. The duty did not start until August 22.

Worked check: a steel line either side of September 15

The goods: steel structures and parts, HTS 7308.90.95, product of Canada, general rate free, entered value $10,000. Subheading 7308.90.95 is a derivative steel article in note 16(c)(iv), so heading 9903.82.02 applies Section 232 duty of 50 percent on the full customs value, and note 16(b) collects it in addition to any special rate, so a USMCA claim does not remove it either. The subheading was added to the motor-vehicle list from September 15, 2026.

On September 16, Proclamation 11065 says the motor-vehicle duty applies "in addition to duties imposed pursuant to section 232," and 9903.03.15 is not available because the line is not under 9903.03.13. The arithmetic: $10,000 × 50% = $5,000 Section 232 duty, plus $10,000 × 50% = $5,000 Section 338 duty, an effective 100 percent. The forced-labor duty stays off because note 52(f) excludes the 9903.82 metal headings. A September 16 line keyed with 9903.03.15 is short $5,000. Check the line with its entry date in the duty calculator.

How do I audit Section 338 on past entries?

1. Select Canadian-origin lines entered from August 22, 2026. Include warehouse withdrawals from that date.
2. Match each line's subheading to the list in force on its entry date: the August 22, September 15 or October 30 version of note 51(b). CBP attached each version to its CSMS message.
3. Check the heading. A listed line needs 9903.03.12, .13 or .14. A dairy-list Section 232 article can use 9903.03.15; nothing else can from September 15. Civil aircraft goods use 9903.03.16.
4. Check the USMCA effect separately. The claim should remove the base rate and the forced-labor duty, never the Section 338 duty.
5. Recompute each line: 50 percent of entered value, plus the other programs, added side by side.
6. List both directions. Missing Section 338 numbers are underpayments for a correction or disclosure; numbers on lines entered before August 22 or on delisted subheadings are overpayments for a correction or protest. Your broker files them.

A post-entry audit tool such as TariffSense reads the 7501s or broker exports, checks every Canadian line against the note 51 list for its entry date and flags missing or unneeded Section 338 numbers line by line. The 2026 duty stack by entry date shows how the duty sits with the other 2026 windows, the 9903 lines on your entry summary explains each Chapter 99 number, and the post-entry audit guide covers the rest of the line. Confirm any correction or claim with a licensed customs broker or trade counsel before it is filed.