9903.03.15 Explained: Section 338 Canada Section 232 Exception

Key Points

• 9903.03.15 is an exemption heading carrying a 0 percent additional duty rate: it removes the Section 338 Canada surcharge from goods already subject to the Section 232 actions listed in U.S. note 51(c).
• The heading became effective August 22, 2026. Entries before that date are not covered by this exception.
• As of September 15, 2026, the scope of this exception narrowed significantly: it now applies only to the dairy heading 9903.03.13. The alcohol heading 9903.03.12 and the motor-vehicle heading 9903.03.14 are no longer shielded by 9903.03.15, and those duties now stack on Section 232 articles.
• Legal authority comes from Proclamations 11046, 11047, and 11048, U.S. note 51(c) of Chapter 99 of the HTSUS, and the scope proclamations of September 8, 2026 (effective September 15, 2026), confirmed in CSMS 69851916.
• Confirm that each specific article is enumerated in U.S. note 51(c) before filing; general Section 232 exposure is not enough to qualify.

On this page

1. What 9903.03.15 is and where it comes from
2. The rate: zero percent additional duty
3. Effective date and entry timing
4. Scope: which goods and countries are covered
5. What changed on September 15, 2026
6. How 9903.03.15 appears on a customs entry
7. Stacking considerations
8. What importers should do
9. Key references

HTS 9903.03.15 is an exemption heading, not a duty-imposing one. It carries a zero percent additional duty rate and applies to articles already subject to the Section 232 actions listed in U.S. note 51(c), shielding those goods from the broader Section 338 Canada duties. The heading has been in effect since August 22, 2026. As of October 6, 2026, its scope has narrowed: since September 15, 2026, it covers only the dairy heading 9903.03.13, not the alcohol or motor-vehicle headings. The links in this article go to the primary documents: the proclamations, Federal Register notices, and official tariff schedule pages themselves. Read the source.

What 9903.03.15 is and where it comes from

9903.03.15 sits inside the Section 338 Canada action block in Chapter 99 of the HTSUS. The foundational legal authorities for this block are Proclamations 11046, 11047, and 11048, together with U.S. note 51(c) of Chapter 99. The scope of the exception was subsequently modified by the proclamations of September 8, 2026, effective September 15, 2026, as confirmed in CBP CSMS message 69851916.

The official heading text reads: "Exception: articles subject to the Section 232 actions enumerated in U.S. note 51(c) -- no additional duty." That language makes the purpose clear: this code identifies goods that are already being disciplined under specific Section 232 measures and excludes them from stacking an additional Section 338 Canada duty on top. However, the practical reach of that exception changed materially on September 15, 2026, as described below.

It is important not to confuse this heading with the older 9903.03.01 through 9903.03.11 block, which was a separate Section 122 program with a different rate and a different legal basis. Those codes are unrelated to 9903.03.15.

The rate: zero percent additional duty

9903.03.15 imposes no additional duty. The rate is 0 percent. Claiming this heading on an entry means the importer is asserting that the goods fall within the Section 232 actions enumerated in U.S. note 51(c) and therefore no Section 338 Canada surcharge applies to those goods.

The rate itself has not changed. What changed on September 15, 2026 is the set of Section 338 headings whose goods can still invoke this exception. Prior to that date, the exception was available against all Section 232-covered goods in the Section 338 Canada block. From September 15, 2026 onward, the exception applies only where the competing heading is 9903.03.13 (dairy). The headings 9903.03.12 (alcohol) and 9903.03.14 (motor vehicles) now stack their duties on Section 232 articles rather than yielding to this exception.

Effective date and entry timing

This heading became available for use on entries made on or after August 22, 2026. Entries before that date are not covered, and importers should not attempt to claim 9903.03.15 on pre-effective-date entries.

The narrowed scope under the September 8, 2026 proclamations took effect on September 15, 2026. For entries filed on or after that date, 9903.03.15 is effective only for goods that would otherwise be subject to the dairy heading 9903.03.13. Entries filed between August 22, 2026 and September 14, 2026 followed the broader original scope. See the official HTSUS online edition at hts.usitc.gov for the authoritative text of U.S. note 51(c) and the full Chapter 99 structure.

Scope: which goods and countries are covered

Country of origin

This heading is part of the Section 338 Canada action. It applies to goods of Canadian origin. If your goods do not originate in Canada, this heading is not relevant to your entry. Confirm country-of-origin determinations with your broker before filing.

Product scope

The heading covers articles that are already subject to the specific Section 232 actions enumerated in U.S. note 51(c). As of October 6, 2026, following the September 15, 2026 scope change, the practical effect of this exception is limited to goods that would otherwise also fall under the dairy heading 9903.03.13. Importers must consult the current HTSUS U.S. note 51(c) directly at hts.usitc.gov, or work with a licensed customs broker, to confirm whether a specific article qualifies. Do not assume a product is within scope based on general knowledge of Section 232 programs; the note's enumeration controls.

What changed on September 15, 2026

Before September 15, 2026, heading 9903.03.15 operated as a broad exception shielding all goods covered by the Section 232 actions in U.S. note 51(c) from additional Section 338 Canada duties, including those that would otherwise have attracted the alcohol surcharge (9903.03.12) or the motor-vehicle surcharge (9903.03.14).

The proclamations of September 8, 2026, effective September 15, 2026 and confirmed in CSMS 69851916, changed that. From that date:

• 9903.03.15 continues to except Section 232 articles from the dairy heading 9903.03.13.
• The alcohol duties under 9903.03.12 and the motor-vehicle duties under 9903.03.14 now stack on Section 232 articles. Those headings no longer defer to this exception.

Importers who were relying on 9903.03.15 to avoid stacking Section 338 duties on alcohol or motor-vehicle goods should treat entries filed on or after September 15, 2026 differently from earlier entries. Review your post-summary correction exposure accordingly and consult the CBP website for any additional CSMS guidance.

How 9903.03.15 appears on a customs entry

Chapter 99 codes ride alongside, not instead of, the regular classification in chapters 1 through 97. On a CBP entry, the entry will show:

• The substantive chapter 1-97 HTS classification for the article (which determines the base MFN or preferential rate).
• The Chapter 99 code 9903.03.15 as a secondary line, asserting the Section 338 Canada Section 232 exception.

When validly claimed, no Section 338 Canada additional duty is assessed for the covered heading. The base duty from the chapter 1-97 classification still applies, as do any other applicable duties not displaced by this exception. Note that as of September 15, 2026, this exception no longer displaces the alcohol or motor-vehicle Section 338 duties for goods also covered by Section 232. Confirm the full stacking picture with your broker.

For a broader look at the other Section 338 Canada headings, see our articles on 9903.03.12 (Canadian alcohol) and 9903.03.14 (Canadian motor vehicles).

Stacking considerations

Claiming 9903.03.15 removes the Section 338 Canada layer only where the exception still applies. From September 15, 2026 onward, that is limited to the dairy heading 9903.03.13. It does not remove:

• The ordinary column 1 (MFN) duty from the article's chapter 1-97 classification.
• Any Section 232 duty that attaches to the article under the actions referenced in U.S. note 51(c), which remain in effect and still apply.
• The alcohol duties under 9903.03.12 or the motor-vehicle duties under 9903.03.14, which now stack on Section 232 articles as of September 15, 2026.
• Any other Chapter 99 surcharges that may apply to the goods under separate legal authorities.

The exception does not create a duty-free result by itself. It prevents one specific layer of Section 338 Canada charges from stacking on top of Section 232 charges, but only for the dairy category from September 15, 2026 forward. The total duty bill must be computed across all applicable codes. Use the duty calculator to model these scenarios, and check the 2026 tariff code overview for broader context on Chapter 99 structure.

What importers should do

1. Reassess your September 15, 2026 cutover. If you have been claiming 9903.03.15 to avoid stacking Section 338 alcohol (9903.03.12) or motor-vehicle (9903.03.14) duties on Section 232 articles, that position is no longer supported for entries on or after September 15, 2026. Evaluate whether post-summary corrections are required.
2. Verify U.S. note 51(c) scope for dairy goods. Pull the current HTSUS Chapter 99 text from hts.usitc.gov and confirm that each of your Canadian-origin dairy articles is actually enumerated in U.S. note 51(c). Do not assume eligibility based on a general Section 232 exposure.
3. Update your entry instructions and ACE templates. Your customs broker needs to apply 9903.03.15 only where it still applies, and add 9903.03.12 or 9903.03.14 secondary lines for alcohol and motor-vehicle goods where the stacking now applies. Review templates for all shipments on or after September 15, 2026.
4. Model your full duty stack. Compute total landed cost accounting for the base chapter 1-97 rate, the applicable Section 232 duty, and the correct Section 338 layer. The duty calculator can help you model these scenarios.
5. Keep records supporting the exception claim. If CBP questions the 9903.03.15 claim, you need documentation showing Canadian origin and that the article falls within the Section 232 actions enumerated in U.S. note 51(c) and within the narrowed dairy scope effective September 15, 2026. Maintain those records in line with your standard recordkeeping obligations.

Key references

• HTSUS online edition, hts.usitc.gov: authoritative text of Chapter 99, including U.S. note 51(c) and heading 9903.03.15.
• White House proclamations page: Proclamations 11046, 11047, and 11048 (foundational Section 338 Canada authority) and the scope proclamations of September 8, 2026 (effective September 15, 2026).
• Federal Register, federalregister.gov: Federal Register notices implementing the Section 338 Canada measures and the September 2026 scope changes.
• U.S. Customs and Border Protection, cbp.gov: CSMS 69851916 confirming the September 15, 2026 scope change, and CBP guidance on entry filing requirements for Chapter 99 codes.